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MG MGF Technical - Technical Advice re: HGF Required

Ok so I know there has been many many threads regarding HGF. Here goes any way...... I'm the second owner of a 1.8MPI 1997 P reg with nearly 53,000 miles on the clock I bought the car about three weeks ago and last night the Head Gasket Went just above the Alternator. Switched of just as the water temp gauge was approaching the normal marker (normally gauge sits one mark lower).

I'm going to change the HG myself and will be happy to report back my findings along the way.
So here is the question for you technical minded out there: Has anyone else done a DIY replacement and if so what should I look out for and should anything else be replaced as a matter of course after a HGF.

Cheers in advance

Russ Fitz
Russ Fitz

Russ, if you're not a very very good mechanic don't even bother DIY, you need to take apart the engine, and I saw it several times in the garage, it looks like a REAL mess when it gets replaced!
Dirk

I did not DIY mine but, my water temp gauge did not rise that much above normal and I still needed the cylinder heads skimmed because of slight damage.
Ralph

Dirk

Been doing all my own servicing including cambelt, camshafts, clutch replacements and HG replacements on SOHC engines etc for over ten years. Just need some advice on the Rover DOHC engine.

Re: "...if you're not a very very good mechanic don't even bother DIY"

I'm a Degree qualified mechanical design engineer does that count?

Thanks for your feedback so far.

Russ
Russ Fitz

Hi Russ

Any feed back would be very useful. The failure in your car has occured in the 'usual area' - ie above the alternator. Of course it would be even more useful to have had temperature sensors in the cooling system and in the engine block itself WHILST the HGF was occuring, but that is never likely to happen unfortunately.

I think there are a number of things to check. Inspect the HG, looking for evidence of the bead failure that seems to occur. Also check the normal operation of the auto-air-bleed joggle valve near the inlet manifold. As it is an MPi, check also the condition of the inlet manifold that may have had a low grade water leak (older cars have a gasket material that is prone to drying and hardening). Your car is 3 years old, so check the condition of the coolant runs under the car to the radiator.
Other things to check are the correct operation of the thermostat, and replace the expansion bottle cap (at 4 quid it seems silly not to).

Depending on your motivation, you might also want to consider the remote thermostat that has been recently described to us by Simon when you come to reassemble the engine. Some operational data on this solution would be very useful in the context of a standard engine.

Good luck with the HG replacement. There are a number of specific technical points regarding K-series engine rebuilds that you probably know about already (like checking the lengths of the engine long bolts etc)- and Roger P is probably the best source of advice on this matter.

Rob
Rob Bell

Russ,

I would suggest the purchase of the MGF workshop manual and also the K series engine manual (no, the w/s manual doesn't cover the innards of the engine!) if you haven't already.
If you search the archives, you'll find the part numbers.

If you say it has failed over the alternator, it sounds like you may have the problem with inlet manifold that is "known" with 1.8i's. Once again, check the archive for details. I remember a thread that pointed to a site that had pictures of an engine with a failure in this area literally squiting coolant out... Might be worth talking to MGR about a replacement for that, though they might not do much on a '97 - depends what sort of service / fault history its had according to their records...

If all else fails and you get stuck (he's got a trailor!), I can recommend Meltech at Stokenchurch if you're in South Bucks. He used to do one of the Priests cup cars, (so does understand F's). Small workshop at the back of his house = lower costs = lower rates, but still good workmanship (he's replacing the water pump on the wife's Astra today for me!).

Good luck,

Neil.

Neil

Thanks for all your feedback so far...keep it coming.

Rob

Thanks for the info, where can I get GOOD technical info for things like bolt length checking? Got workshop manual but I'm not too impressed with it! Pictures are nice though... :-)

Neil

I'm just a stones throw from your area I'm in High Wycombe so will bear in mind your recommendation, cheers!

Thanks to all again

Russ
Russ Fitz

I haven't got the practical experience to help you there (not on a K-series anyway!).

You might get some interesting tips from David Andrew's K-series tuning site (although the through-bolt length isn't mentioned- I've looked)- and anyway, it is an interesting read. The page can be found at http://members.aol.com/_ht_a/DVAndrews/kengine.htm

Others will be able to advise further.

Rob
Rob Bell

Roger, Carl or Dieter may well be able to answer your questions more specifically.

I haven't got the "engine" book, but it would sound like the type of info that ought to be in there, I would have thought...

Might be worth getting one of Mr Satur's "enhanced" replacement gaskits, perhaps?

I'm sure you know about the "motor engineering" place up in Cressex (on the bend in Lancaster Road) that should be able to tell you if all is "true" and do the appropriate grindings if it isn't (there may be others as well that can do this...). They were recommended to me by someone, can't remember who now...

Stupid thought... Is there a Haynes manual that covers a car that has the K series engine in it - surely there must be - that would have "how to check your bolt lengths" in it I would have thought.... There's not going to be a world of difference in checking that kind of thing on a 1.8 or a 1.4 or 1.6...

Neil.

Neil.
Neil

The Haynes manual for the K-series Metro/114 has enough info in it, assuming that you can work out the 'simple' bits yourself (like dismantling the induction system etc). There is also a Haynes manual for the later 200/400 which covers the K-series (it'll be a bit more up-to-date than the Metro one). I've removed/stripped/rebuilt/refitted my K-series head using just the Haynes manual, it doesn't require any special skills and isn't particularly difficult.

The most important thing is to put the crank in the right position before you take the head off, and NOT to turn the crank whilst the head is off.

I found that when I lifted the head off it splurged coolant into the pots - not a huge problem as long as you mop it up, spray with WD40 to prevent the liners & rings rusting, and change the oil afterwards to catch whatever made it through to the sump.

This isn't a hard DIY job if you're reasonably mechanically-minded & methodical.

Mike
Mike Bees

Russ

Like Rob I have no personal experience advice (on K series engines) but would love to hear your report.

BTW don't mind Dirk - to him checking the oil & water is a difficult mechanical job:-)

Ted
Ted Newman


Well said Ted, I mean Dork states "don't even bother DIY, you need to take apart the engine" hmmm is that right, you don't say. Stick to combing your hair Dork it suits you better.
Bob

Russ
Replacing an MGF HG is nothing to fear, really, if you've got some mechanical experience.
However, a workshop manual is essential to find essential info like torque settings and various other tricks like bleeding the cooling system, cam timing etc.

For head bolt elongation: as far as I can understand the part of the bolts that are prone to stretching is the threaded portion. The bolts are M9. If they can be threaded all the way by finger force with the cylinder head removed they should be OK.

The only thing that you should replace while you're at it is the cam belt.

Don't forget to have the mating surfaced clean and dry when you fit the head. If your cooling system is dirty you should take the opportunity to clean it out before filling it with antifreeze.

On Dieter's page you will find out more about HGFs and the theories around them. My opinion is that it it the gasket itself that badly constructed. Put your fingernail against the sealing strip on your blown one and you'll understand what I mean.

If you join the MGOC you will have free technical support during your HG job, and all other problems you may have with your MG. I got plenty of of essential advice from them during my HGF job and can sure recommend it.
jon

Hi,

For those who have chosen alternative bedtime reading material, the MGF workshop manual does have instructions on changing the head gasket. K-series Haynes manuals also offer advice, but aren't infallible. There's no mention of checking the head bolts in the F manual: bolt lengths are given in the Haynes manual but I would wait a more authoritative source than my ageing library.

Russ, although I haven't changed the gasket on my F I have on my 214, and with the exception of access they are virtually the same. It is relatively straight-forward, although there might be a moment of panic half-way through when you see all the components spread around the garage. It took me about two days to do, working steadily with the usual breaks. That is, half an hour to change the gasket and the remaining 47.5 stripping it down and putting it all back again. You will need:

Camgear locking tool - about £3.50, but an incredible £15 at Halfords, so don't buy one there.
Flywheel locking tool - unobtainable, but Pickavant supply a 'Locking rod' in their Rover kit. I don't know where that goes. I used part of a farm gate hinge, a rectangular plate with the hinge hangar welded on to it (we are rural here). I ground a vee on one edge of the plate and it fitted into the flywheel teeth pretty well. You have to take off the starter, of course.
E12 Torx socket.
Lots of combinations of small sockets to get the cambelt covers off, a real pain, and the usual tools and torque wrench.
Elastoplast.
Exhaust manifold gasket, cam cover gasket, cambelt.
Unipart SuperPlus 3 antifreeze.

Oh yes, head gasket. You may wish to try Mike Satur's toughened gasket, I would advise mailing him. He has an excellent reputation with F components.

When the cambelt is taken off an the gears locking tool released the gears will scarily jerk round under the pressure of the valve springs. All these components are marked so it's fairly straight-forward to reassemble them, although not so easy in the F to check it. After you've done this I would have a break, then come back and check the assembly again very thoroughly, it has to be correct.

I disconnected the lambda sensor multiplug and dropped the exhaust manifold just enough to clear the head studs. As it seemed a hellish job to dismantle the inlet manifold components I released it from the head and gently pulled the whole lot back from the head on its flexible pipes. The head can then be lifted and replaced without any of the manifolds, a far easier job.

When the head is lifted the cylinders will, as Mike says, have an alarming amount of coolant in them. Just mop up with paper towels. When you turn the head over oil will run all over the place, so have plenty of newspaper ready. It's probably best to turn it over and just let it drain.

Now that the head is off and open you can see just what a marvel of production engineering the K-series engine is. OK, the head gasket is weak, but the engine is a real gem.

The cylinder liner holding tools are not essential if the head goes back on within a reasonable time and the engine is not touched whilst the head is off.

Perhaps two people are an advantage when refitting the head. The last thing you want to do is damage the new gasket, so make sure the head is held in the same horizontal plane as the block and not dropped onto the gasket sealing track whilst you struggle to locate the dowels. The front of the head juts over the front of the block by a few centimetres, which might be a help.

The rest is just standard practice. If you do take the inlet manifold off it might be a good idea to fit the improved manifold gasket and studs.

I tensioned the new cambelt by pulling up the tensioner by hand, that feeble tensioner spring is not much use at all.

Enough has been written elsewhere about filling the cooling system. Steadily and carefully is about all I can add to that.

Whilst removing the head some of the free-flowing oil might have entered the coolant passages. When all is done, and the engine is restarted, this will eventually show as crud on the sides of the expansion tank. Just stick your finger in and wipe it away with a paper towel. Whether you want to flush the cooling system again is up to you. It might be better, once the cooling system is free of airlocks, to leave well alone.

By the way, if a new Rover gasket is bought, are there any visible differences between the new and the old, and does it come with new dowels, and if so, are they steel?

That's about all I can think of. Follow as much, or as little, of this as you wish. Good luck, Kes.
Kes

Kes

Many thanks for the real life info. Just what I'm looking for, got a standard Rover HG (no dowels supplied) cost arround £25 inc VAT does this seem about right? The old one lasted nearly 53,000 and as I don't really thrash the car thought another Rover HG was worth a try.

Where did you get your cam locking tool for £3.50 from?

Probably going to do the job over the coming weekend will try to take some photos when I remember and not scratching my head!

So all good info up to the weekend is very usefull. Thanks to all so far.

Russ
Russ Fitz

Hi,

<a few centimetres>

Damn. A few millimetres, of course. Well, about a quarter of an inch or so.

My Rover head gasket cost £23.75 plus VAT (before discount - I always ask for discount on spares and get it!). The old one lasted 60k but had been weeping at the usual place for some time.

I bought the cam locking tool (just a piece of coloured extruded alloy) from Rover, but you can get them from any Car spares shop. You could always check the price in Halfords first.

Good luck again, just think of your credibility on the BBS when the jobs finished!

Regards, Kes.
Kes

The camshafts have a hexagonal portion where a 24mm spanner will fit. Better than a camwheel locking tool!

One important thing: turn the crankshaft to 90deg (i.e. all pistons halfway up/down the bores - equally high) and leave it there. Then you may turn the camshafs as you like without risking valve/piston collisions.

Right, Dirk?
Jon

Another thought, which I'm sure has come up in one of the "cooling" threads.

The book says to fill with coolant and bleed. Then run the engine until the fan runs, and then go through the bleed procedure again. The fan can run when the engine is hot, but before the thermostat has opened (much). This means you still haven't had much flow to the radiator. Better to run the engine until the radiator itself has got hot - that way you're sure it has seen water (and air bubble) flow before you bleed.

Mel's (Meltech) comment was "it'll take you a while to do properly".

Good luck

Neil.
Neil

Hey Ted, have you ever assisted at a HGF replacement? At least the MGF saga gave me a lot of insights in car mechanics and an MGF in general. I saw nearly everything disassembled & explained to me!

And Bob, why don't you just go home & w*nk in front of your TV?
Dirk

Hi Dirk

As I am a fully trained and qualified motor mechanic I do not ASSIST at head gasket changes or any other vehicle jobs, I actually do the work myself.

True I no longer practise my 'art' in a professional way but I do still practise my 'art'.

Ted
Ted Newman

Neil
Re. bleeding the cooling system: Overheating due to air trapped in the cylinder head's cooling jacket is of course what may cause damage to a freshly replaced head gasket. The jiggle valve in the inlet manifold may work as a one-way valve when it has to let out large quantities of air.
Filling the system through the jiggle valve's hose connection efficiently fills the cylinder head water jacket. After bleeding the system filled up with clean water: jack up the rear of the car, unscrew the radiator bleeding plug and fill 5 litres of antifreeze through the expansion bottle. Refit the plug when the bottle is half full.

And Dirk - why should Bob wink in front of his telly...?

Jon

OK! if you don't stop throwing insults at each other I'm going to send my friend bennie round to fill your wellies with cement!

Right to keep this thread on track here is the latest:

I'm heading in this direction at the moment:

1) Standard rover HG as a replacement.
2) Replace cambelt - was going to do this before HGF.
3) Replace intake manifold gasket £4.11 + VAT.
4) Replace cam cover gasket £15.65 + VAT.
5) Replace exhaust manifold gasket £4.25 + VAT.
6) OH! yes and coolant.

Cylinder head bolts are £6.50 + VAT each x 10 = £65 + VAT. So am going to have a look at them first.

Also going to do 60K service early so will also replace: Oil, Oil filter, Spark plugs, HT leads, fuel filter, air filter etc.

Also going to order Stainless steel hose clamp set from Mike.S ....... that will do for now.

I'm going to take my time so probably will take longer than just the weekend, will keep you posted.....

Keep the GOOD technical info coming please...

Oh yes! Dirk, Ted and Bob Bennie has his mixer running! (More than my MGF does at the moment)

Cheers

Russ
Russ Fitz

I bought my cam locking tool from Draper's website, £2.47 including delivery!

Search for part number 52306 on www.drapertools.com

Mike
Mike Bees

Russ

With the sort of mileage your engine has covered it may even be an idea replacing the cam shaft seals and maybe even the valves stem seals as a precaution.

If your cylinder head is pitted from corrosion (which is likely) you may need to have it skimmed. For some reason the limit is just .2mm, so tell the machinist to be careful with the milling machine.

Too bad Luxembourg is so far from Buckinghamshire, you might use an experienced assistant during your HG job...
Jon A. Fredheim

Mike

Cheers Mike Excellent info!

Thanks again

Russ
Russ Fitz

All good stuff - not much to add save my local mechanic reckons he can get head out complete with inlet manifold attached.

The latter is a pain to get off in situ - much sticking plaster used :-(

Fiddly bit will be the cam belt tensioner - I wrote something on this years ago when I did mine (twice as it turned out) Check the archives.

Suggest adding oil/filter/plugs to the list.

You'll need instructions for torquing up head bolts - again in archive somewhere

But my main advice - are you sure it's not the mpi inlet manifold gasket as rob mentioned. It leaks into and just below no. 4 cyl inlet but can run left to right round head/block joint to the front of engine before descending.

jt
John Thomas

JT

Nope! it is certainly coming out just above alternator in a nice little water jet. Can see it with a mirror and I think the rubber like joint seems to be visible at this point too, will report back after closer inspection.

Russ
Russ Fitz

Russ - have you considered Mike S's performance gasket? Not much more pricey.

I have a copy (if I can still find it) of the torquing procedure - can email it to you if you send an addy to me.

E
Ed Clarke

Ed

Thanks anyway but i've already got a HG from Rover. I've got the workshop manual hasn't that got the setting in it?

Thanks though and cheers

Russ
Russ Fitz

Don't have the manual so can't tell you! So long as it has the bit about tightening to a particular torque (can't remember what) and then 180deg on all bolts, and then another 180deg on all bolts... that's the only wacky bit I remember.

E
Ed Clarke

The data are all included, the torque the tension bolt lenght also as mentioned in the archive (link on top right of this page)

Not included is the instruction on looking for the jiggle valve RH of the air intake manifold.
http://www.lame-delegation.de/mgf-net.de/bleed/index.htm

Good luck on the repair

Dieter

Dieter Koennecke

Rus, Just make sure it is not just the inlet manifold gasket leaking - it will save a lot of heartache. Leaks from here can hang on the edge of the HG and run round appearing some where else. If you change the manifold gasket make sure it is the latest green one. The earlier black one had a lower heat tolerance and collapsed causing the manifold to loosen and a quite severe water leak.
Terry Cox

Gentelemen: Where is this inlet manifold gasket? I got very upset with my F on Wednesday evening while driving home. I saw ahuge cloud of steam and dreaded the worst. I drove the 1.5KM back to work and took the company car home. When I got to work the nest morning and take off the engine cover, I noticed a stream of water squirting out between the two cylinders closest to the air cleaner. It's pretty hard to see exactly where the water is coming from, but it's definitely not near the alternator. Can I stop being worried? I thought I had cursed myself by reading all about replacing a head gasket, as this happened the same day that i firs read this thread.
James

James,
I wouldn't bore here all and always with the same bulk of picture links. They are as mentioned in the BBS archive. Also I'm tired 1:00 am here ;)

Try the MGF technical term search engine on
http://www.mgcc.de/mgf
for all web documents to MGF technical terms until the Europeans get up.

Good night
Dieter
Dieter Koennecke

I should mention that the leak is on the exhaust side, and squirting directly on the the exhaust manifold
James

James

Sad to tell - seems like you've joined the club...

On the exhaust side of the engine there is hardly any other potential leaking points than a failed head gasket.
Jon

Guys, I've just written a spiel in one of the other threads about this HGF problem. I just can't understand why MGR are doing nothing about it? Why aren't they looking after their customers better than what they are? I think it's about time we got militant with MGR over this issue and get these bastards shocked into action. This is a latent defect and these w*nkers sit by without offering any assistance? I reckon you blokes in the UK need to get together and start protesting to MGR in a very public manner. Embarass them, provoke them do whatever is necessary to get these guys listening to your problem and proactive into helping people out.

JB
JB

To our dear Ozzie friend - what the hell do you think we have been doing for last 5 years!! Have a look at Dirks' Hall of Shame and follow its trail backwards for christ sake!

And I am sure that if the problem was as easily solved as our 'ball&chainer' seems to think MGR would have done something about it by now.

From what we have seen the only cure is to scrap the mid-engine MGF layout as I am assured that these failures are not so prevelant with other K series engine cars.

A.N.Effer.
A.N. Effer

OK guys if you don't calm down I'm gona send me mate Bennie round to fill your wellies wiv de cement.

Try to stick to the point of the thread please ie technical issues when DIY fixing the HGF.

Cheers

Russ
Russ Fitz

>> I am assured that these failures are not so prevelant with other K series engine cars <<

I've heard of HGFs on other Rovers that use the K series 1.8 engine, although the Cooling system on the MGF does make the situation worse.

>> scrap the mid-engine MGF layout <<

That's a bit extreme, other mid engined cars don't blow head gaskets all the time. Revise the cooling system & keep the engine where it is.

Steve.
Steve Childs


Russ, why not change the thermostat for an 82 deg.C one + 2 pcs. of 3 mm holes in it while You have the head off and it is easily (and cheaply) done ?
See John and Dieter threads earlier on for more details.

Regards , Carl.
Carl

Yesterday I changed the head of another F for a modified one. No gasket failures to consider but the work is similar.

However before delving into this there are heated words based on perhaps a lack of knowledge and understanding. There is an issue with gasket failures on MGF, but this is clearly more prevelant on cars built in the 1997/8 period. These cars also seem to be able to suffer repeat failures.

I have noted a marked reduction in the incidence of failure in cars after 1999. Why? Well there are a raft of changes to the engines by those who have been sitting on their bums!! There is a valid point in terms of support for those who have cars in this succeptable period and suffer from failure.

Yesterdays change was on an MPi and retained the plastic manifold. I noted that the head gasket set was sourced direct from Rover central parts store and it contained a gasket with some features I have not seen before. The stamped in part number was also different to the ones I have viewed before, even recently. This gasket had additional blocks of the sealant material at the front end of the gasket in the general area of the breather passages that allows oil to return to the sump.

I also used new steel dowels to locate the head to block, which is creating a far more rigid connection than can be achieved by the original plastic dowels. The cam belt was also changed.

I find that doing this job on an F takes about 50% longer than a FWD car simply from the restricted position of the engine. It isn't actually difficult to do, it's just bloody awkward to do certain aspects.

I have removed heads with inlet manifolds before but on balance I find it easier to remove the manifold and leave that in the engine bay. The slightly difficult positioning of the manifold to head nuts (7 off, 4 underneath) is offset by not needing to remove electrical connections from the engine managment components on the manifold nor break into the fuel system and have a degree of spillage, however careful you are.

If you are removing the head to either change or just for a gasket change then the lump, although much lighter than many heads, is far easier to man handle without manifold.

BTW remove the header tank (2 x 8mm headed bolts and lift out of engagement with the lower rubber locator and then you can get at the lower hose) and also remove the dipstick/filler abortion. One bolt fixing to the inlet manifold, watch the spacer between the assembly and manifold, then reach under the assembly where it attaches to the dipstick steel pipe and lift the collar and it will slide up and clear of the engine bay. Revel in the extra room this gives!!

Always check that the jiggle valve in the cambelt end of the engine is free as this makes the coolant refil and bleed procedure so much easier. I usually give it a little WD40 or similar to help it along.

Positioning the engine prior to removal of the belt is a doddle and there are plenty of marks. However note that the cam wheels are the same on MPi models for both cams and have identical marks. On one side you will see inlet and a notch in the toothed edge of the wheel and on the opposite side you see exhaust with a similar notch in the wheel edge. Under the locking bolt washer are two slots for the roll pin that provides location on the cam. These too are marked in and ex.

I raise these points to ensure that you are aware that you must fit to the correct holes for the cam your fitting the wheel too. I make a simple mark just top ensure that I refit the same wheel to the same cam. Not vital as long as the correct p[osition is adopted, but it makes for a simpler refit if you do mark each.

Cambelt changes require that the bottom pulley is removed. This is something that I cheat with as I have air tools that makes light work of tight bottom pulley bolts. However this should be lossened long before the head is removed, using whatever long levers and extensions etc suitable for the purpose.

Oh whilst in this area you have to remove the alternatoir drive belt and just to add to the problem there is a very small bolt that sits in the alternator, with it's head sticking into the adjuster bracket. This means that you undo all the nuts and bolts to find that the alternator won't adjust. You have to disengage this hidden bolt first.

Cam belt removal needs the engine mounting on the offside to be removed and the engine supported. The 18mm nuts and bolts for engine mountings are long standing, but still an odd size. The cramped engine bay of the MGF doesn't allow good access for a socket and damn all for any other tool. Use of a long lever is likely!!

To remove the mounting requires that the two main bolts to the engine bracket are removed and the nut onto the body rubber. Then there is the torqur reaction arm that has to be detatched and you thinlk that's it. It is until you try and lift off the bracket!! There is a steel rod cage preventing it from being removed and this is held on by two 13mm headed bolts. Problem is that one is completely hidden! Undo the one you can see and then use a lever to push the road towards the outside of the wheelarch. This gives enough room (just) to slide the bracket up and off.

I suggest that you leave the mount in place (loosened nuts and bolts first though) until the engine through bolts and other high torque bolts are removed or at least loosened and once this bracket is out the engine flops around like a wet blanket.

Actual removal of the bolts holding the wheels to the cams can be somewhat trying!!! The engine position does you no favours here. There is a proper tool for locking the two wheels together (see Haynes)and this can be fabricated reasonably easily. This lockout tool is required whilst you crack the bolts on each wheel. It being a good job that there is a 17mm head on these bolts!!

Cam wheel removal is needed because the belt backing plastic cover is attached to both the head and block and is a continuous run down the exhaust side of the engine. Accidental breakage of this at a seam level with the head face line seems reasonably common and can allow the head to be removed without taking the cam wheels off, however you can't retain the cams in the correct timed positions as the centre two through bolts have their heads slightly covered by casting sections that protrude from each cam. It is vital that your E12 socket has full engagement on the head of each bolt at all times your loosening and ticghtening these. The cams have to be turned more to allow the wide head to pass the cams before you can remove them.

Bolt lengths are critical and have to be checked properly. One aspect not mentioned in this respect is the effect that head skimming has on their function. This isn't mentioned in the workshop manuals since the maximum approved skim is so small it poses no threat. However if a skim of much greater thickness is done then if the bolts are at the end of the permitted tolerance then this skim can undermine the result and thus lead to problems form reduced clamping load, plus perhaps distortion resulting from reduced rigidity of the head face.

Just bear this in mind when the common and uneducated comments come thick and fast that because your head gasket has gone you must have the head skimmed. NOT TRUE. Fact - if you have the head off the car for any reason then use a straight edge and measure for any face distortion and if present measure it and see if it is inside or outside tolerance and act appropriately.

Head bolts are interesting things!! Remove then and store them in the order they came out, so that they return to the same hole and thread. DO NOT DROP them into the holes as you WILL quite easily damage the threads and give your self reasons to cry! Measure them when the head is off by hand tightening them into the hole theu came out off. In use the bolts stretch in the thread area immediately above the section of thread which is inside the receiving thread on the ladder section which is at the bottom of the engine.

Tightening them by hand until you can turn them no more shows where this stretch point starts and where if you were tightening the head down would be leading to no more clamping load on the head, but just additional stretching of the bolt.

At the point where the bolt becomes tight you now measure between the underside of the bolt head to the block and if the measurement is less than 97mm the bolt is serviceable. My own view is that if the measurment is within 3mm of this I renew. I expect to find most bolts with similar lengths. If I find any odd measurements I renew those, and if I find more than 4 odd measurments I renew the lot. 6 plus ukp or not, the job these bolts do is worth the investment.

I mention the 'DON'T TURN THE ENGINE OVER' whilst the head is off again as it is important. That is unless the liners are clamped in place.

If you decide to strip the head then fit ET's fingers and set up the microscope, because if your expereicned at working on A, B and V8 engines then the dimensions of bits and pieces in the K heads will come as a big shock! They are small and need a learnt method to remove and refit efficiently.

When fitting the head back onto the engine, especially when you have replaced the dowels for the steel ones, you will find that the head engagment onto these offers a little resistance. Ensure that the head sits square and ease it on. If you checked that the dowels cleanly fit the holes in the head before refitting the head you will know that it is just a matter of alignement. Take note to follow the procedure for fitting and tightening the through bolts.

Once the head is refitted then you come to the cam belt tightening. Even with the Rover tool for holding the cam wheels in the correct position whilst you fit the belt, I bet most will end up with the belt one tooth out. Especially when a new belt is fitted. This is beacuse the new belt doesn't stretch easily and distortion whilst it has been boxed will take up some of the movement you want.

I get round this by turning the crank back half a tooth. If you look at the crank belt pulley you will have two dimples in the face that are aligned when they straddle a cast in line on the oil pump body. What I do is turn the crank anti clockwise until the right dimple is in line with the oil pump line. (This by just dropping the crank pulley back on and hand turning it.)

Once in this position the belt is fitted as per normal and when engaged and tension added through the tensioner you will be able to turn the crank that half a tooth which will take up the slack properly between the crank and exhaust cam, and you will see the cam marks are sport on. The cam wheels being locked together and being so close to each other means they present no problem and hey presto the cams are correctly timed.

Other hints cover exhaust manifold fit. The heat shield nearest the gearbox has a bracket that is held by the end manifold nut. If you loosely fit the 10mm headed bolt that holds the shield to the bracket so that the thread is just through the captive nut it can be easily moved about to get the exhaust nut in place. The exhaust nut needs the bracket bolt out of the way to gain access to it so doign it this way means that you can easily do both up and not have a fight to locate the small bolt when the braket is tightened byt the exhaust nut.

On the same area those who have had the exhaust rattle cured by dealers fitting the extra steady bracket will find this bracket a real pain in the butt. The reason being that there is no movement of the manifold away from the engine and so you can't remove the exhaust or refit it to the head. When you remove the exhaust nuts often the studs come out as well, and if all come out (as did yesterday, but not all on the previous one) then you will be able to remove, but refitting is a nightmare. Remove the bracket from the engine and refit as a later job. The exhaust studs should be separated from the nuts and fitted to the head before you refit the head to engine.

Everthing else is fairly simple and follows the age old 'refitting is a reversal of the removal procedure' saying! Bleeding the cooling system is not rocket science, but should be done methodically by going round each of the three bleed points and ensuring that air is expelled. I go round at least twice and am only satisfied when I have coolant leaking at the first turn of the bleed plug. (with the expansion cap off)

Also note that operation of the cooling fan is not a clear guide of air in the system. You should really ahve collected all the coolant you can when you drained down the system. By knowing the amount removed, allowing for some loss when the head is lifted, you can judge quite easily when the system should be refilled fully. Any shortfall means an airlock which often have to be coaxed out with a little rapid squeezing of coolant hoses to set up a surge in the system. Running the engine till warm so that the thermostat is open allows the expansion cap to be slowly removed and in turn opening of each blled nipple. You may be surprised to then see and hear air escaping.

Heater output is also a goos guide to airlocks in that circuit. Mediocre heat is common until all locks are out then you can cook toast. Feeling the two main hoses through the spare wheel well area is a good guide to coolant flow in the main circuit. Once hose getting hot and the other not is not a good sign if thew engine has been running more than 10 to 1 minutes. I find that the rapid sqeezing to create a pumping effect held to move things along.

Also note that coolant flow is restricted at idle but holding 1500rpm or more drasitaclly increases the pump flow.

I finally take the car a test drive of about 2 miles using a varied range of revs and not only check levels after but open each blled point as well. For the next few days I also advise coolant level checks first thing in the morning. Overnight cooling and settlement is the most likely time that the lasst remaining air will evacuate the system. Witnessed by a possible drop in coolant level.


Overall I find that taking time and not rushing head removal and refitting with a new cam belt should occupy about 6 to 8 hours.
Rog
Roger Parker

Rog - in amongst this quite humbling level of advice, you mention that HGF is >>clearly more prevelant on cars built in the 1997/8 period<<. So the really early cars didn't have the problem to the same extent? Is there ome known change that caused this, either in materials or processes? Is this from your personal experience or from some other figures?

E (intrigued) '96 F and crossed fingers.
Ed Clarke


Thanks a million Roger ! Saved ,printed and filed for the future - hopefully far future !

Regards , Carl.
Carl

Carl, *g* .. I've got more time, cause the car is younger :)
If the time has come, please take the affiliated pictures. Than it will be much easier for me to do the unwanted job... LOL.

Anyway, I suppose that Roger agrees with hosting his brief description to a webside ncluding credits. I'll include some scans from the workshop manual. (torques i.e.)

Regards
Dieter
Dieter Koennecke

So MGR have finally come up with an improved HG...!

Which confirms my assertion: The basic reason for the MGFs' frequent HGFs is that the gasket itself is of inferior contruction.

Wonder if the the new version will be mentioned subseuqent service bulletins...?
Jon

It bet they will not :).
I also suppose they will not change the part number. Rog would have reported if so, is it ?
Dieter Koennecke

Rod did notice a new part #:

>>The stamped in part number was also different to the ones I have viewed before, even recently<<

Hmm.... Maybe MGR after all have come to the conclusion that all those MGF owners can't be wrong?

Did you take a picture of the new item, Rog? Bet Dieter would love to publish it on his site!
Jon

RODGER

Great feed back! Many Many thanks.

Re:
"I noted that the head gasket set was sourced direct from Rover central parts store and it contained a gasket with some features I have not seen before. The stamped in part number was also different to the ones I have viewed before, even recently".

Can you give some indication of the different stamped in part number? I may have time to try to locate this new number before I put the head back on.

I have some new information on the head bolt length checking + photos will report back when the job is complete.

Cheers

Russ
Russ Fitz

My post intended to be helpful to any who need it. Feel free to copy it etc.

I have not done any detailed study of the cars that have suffered gasket failures within my reasonable shpere of influence, but I could see a surge with cars in the 97/98 period. There has been enough time sicne to show a reduction in the incidence for the newer cars and in the interim 97/98 period cars still seem to pop up with problems. The 96 cars still seem to be less affected.

Changes to the engine were ongoign throughout the period, whilst the actual gasket remained unchanged from 1995. I have seen quite a few changes to castings, noting that in several areas there is extra material, often for additional or alternative thread bosses, but apparently more metal that this simple function needs. Certainly rigidity will be affected by some of these changes. I do not have any contacts within Cofton Hackett (engine works) who can elaborate, even if I had I wonder whether they could anyway!

The head change last week used a gasket which I believe is listed under LVB 000230 and may well come with two steel dowels. perhaps someone who has time can double check this and post a confirmation or otherwise.

I have a picture of the gasket differences which I shall drop to Deiter.


Anything else then drop me a line, I have alot on my plate at the moment which reduces time here.

Rog
Roger Parker

got them. Many thanks, also for the permission un using it for ua all !

Put them together with your description in raw version up to...

http://www.mgf-net.de/hgf/change.htm

Now I still don't understand whether the old part Number got official changed or not. The old is GUG702576HG, is it ?

Looking forward on some help on which is which. Any useful comment apriciated.

Regards
Dieter

Dieter Koennecke

Wow - how lucky we are to have Rog. around, an experienced, clever and literate car mechanic!

If I may comment on one area where Rog said:

>Cambelt changes require that the bottom pulley is removed.
>This is something that I cheat with as I have an air tool that
>makes light work of tight bottom pulley bolts.
>However this should be loosened long before the head is removed,
>using whatever long levers and extensions etc suitable for the purpose.

For those with or without air tools an alternative is to undo the two big bolts holding the starter motor to the engine.
Move the motor out (to the right) to reveal the starter-ring gear - theres no need to disconnect the wiring.
Now use a flat spanner or other strong, longish, thinish bit of metal as a wedge between the ring gear and the housing/block. This is to stop the ring gear/flywheel/crankshaft moving while you attack the tight bottom pulley bolt.

This worked for me after my initial approach of trying to move it with handbrake on, wheels on floor and car in gear failed due to too much compliance in suspension bushes etc

jt
John Thomas


Hi all,
now this gets really interesting ! Jon , some time ago when I saw Your pictures of the head /block assembly I was very puzzeld by the diff. in material at the critical "HGF-point"! When looking at my very early -97 this VVC has more metal at that point. This gives slightly more creeping area for the rubber seal before it is pushed out and the p¤ssing over the alternator starts. It seems to be dependant on how much material that is machined off in order to get a clean straight edge at that place. Anyone else seen this ?

Regards , Carl.
Carl


Thanks Rog, what a top man typing in all that for us less 'spanner'ly' minded.

I think its threads like this that keep the MG banner flying, together with the mods talk. Not, whats your favourite music when the tops town - kids stuff, get back to your escort cabs.

Thanks again Roger, you are a star.

Bob
Bob

Dieter & all

Roger Parker and I seem to have stumbled on the different gaskets at the same time and have exchanged a couple of emails including the photos which I guess are those he has emailed to you.

Here is what I have found from my local MG dealership:

I wanted to replace my failed head gasket (1.8MPI 97 P reg) the parts department looked it up on the computer and it listed the normal GUG702576HG.

However when talking to the “back service desk” (not where the public get parts but where the garage service technicians obtain their parts) they told me that they would fit the above gasket but with additional new steel locating dowels to replace the plastic ones.

They then also produced another gasket kit that already included the steel dowels. They told me that this was fitted to some of the newer K series engines. When I asked if it replaced the previous gasket they said that Rover hadn’t obsoleted the above part number.

I obtained this gasket under part number GUG702613HG this included the two steel dowels and a gasket with a similar silicon track pattern as shown in Rogers pictures, surface of gasket marked with LVB 000230.

Now ask your nice parts department to do a “where used” search on GUG702613HG and see what you get. When I did this it was listed as being used on MGF DOHC 1.8MPI (didn’t notice if it was listed against VVC though).

I am providing this information as a recount of my own experiences and is in no way a recommendation. Personally, I fitted the GUG702613HG gasket last night, as I believe that the small reduction in track area at the front end would slightly increase the distributed compressive forces on the remaining track and together with the ridged steel dowels this can’t be a bad thing! IMHO

I have further information to post regarding head bolts lengths etc, but will do this when I have more time.

Regards to all who have posted information, it seems that an awful lot of information has been exchanged since I first started this thread.

Russ
Russ Fitz

Russ,

Are we talking Arriva H/W here, by any chance?

They've only been doing MG's for a little while, and the man on the desk of the parts dept doesn't seem to have any familiarity with them at all - I'm not convinced the technicians have been doing them that long either. They were a Rover "saloon" dealer before, and the Arriva group do all sorts of cars... Even the salesmen don't seem to know much about the F, or have any particular enthusiasm for it (its just "a car" to them)

The parts man managed to order both the wrong type and quantity of antifreeze for me, despite having a long conversation about colour of liquid and type of car...

I've actually got mine booked in to Arriva next week to have the (lack of) volumetric alarm looked at as this needs access to someone with a testbook (+ a stamp in the book for "anti-corrosion warranty inspection" while they're about it - they were very casual about what this entailed: we just have a quick look around!). I'll see how they fare in that and will then update Paul's dealer guide with my findings...

If you ARE using Arriva, it might be worth a call to someone who has been doing the F for longer (I've used Douglas Grahams in old Windsor for most of my services, and they've done quite a good job and seemed fairly switched on to what's going on in terms of changed specification parts...)

Neil.
Neil

Russ/Neil - I've not used Douglas Grahams in Old Windsor so can't comment on them at all, but have used Priests in Chesham. They are excellent and I would suspect much nearer than DG in Old Windsor for someone Wycombe based. Most importantly Priests do listen to what you are saying and requesting. Arriva in High Wycombe for the MGF have to be somewhat of an unknown quantity right now. A year ago all they could do MGF wise was to sell 2nd hand cars. They certainly were not one of the picked dealers. If you are taking your car there Neil it will be interesting to know the result. But I would second your comment to check what is being said if it is coming from Arriva with one of the known good experiences dealers.

Hope all goes well regardless. Alan
Alan

This thread was discussed between 17/07/2001 and 27/07/2001

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