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MG MGF Technical - HGF

OK I am now convinced my headgasket has failed.

I would like advice on which gasket I should buy?
any mods I should do while doing the repair
can all the work be done from above the engine or will I need access from below
any special tools require
any tips

Many thanks
Robert (Bob) Midget Turbo

Check the liners extend correctly above the block equally - then get a Landrover gasket.

At the same time a pressure reducing thermostat (PRT) is a good buy*, but involves a lot more plumbing (also replace rubber pipework and replace original thermostat with knocked out version)

Yes you an do everything from above, it is quite fiddly.

You will want to get yourself an 8mm ratchet spanner for the thermosat
a set of wobble bars for your ratchet set to get to the manifold bolts.
some long sockets for the same
and a camshaft locking tool for the head

Do the belts at the same time, this requires dropping the engine off one of the mounts with support underneath (undo the bolts from above) because the mount goes thru the hole in the belt.
If you do this you'll need some way of locking the flywheel

and of course you'll need a helpful extra hand to get things aligned when you lower the head back down as you stand in the boot.


* the PRT thermostat appears to be a method of ensuring the static pressure in the head doesn't get too great - when the pressure mounts it opens a wider bypass channel which means that even with the engine running at full tilt and the radiator cold, there is little resistance to water flow and therefore less pressure on the gasket

Will Munns

Thanks Will

Yep I have all the basic tools I will nee I would hope. I have done the manifold before and I do know the need for every extension in the box. :)

Anyway what is the story with the new style "oil rail"?
Robert (Bob) Midget Turbo

The Landrover service bulletin is quite clear that the MLS gasket shouldn't be fitted without the oil rail, however lots of people are getting away with it. I wouldn't risk it though for the sake of £30 and some gasket goo.
Paul Hollingworth

I don't see the point in the rail, the head bolts are still the same and the limiting factor in clamping load.
I've heard a comment that the rail adds to rigidity, but compared with the stiffness the sump adds when tightened up I can't see it would add much.

But I'm open to convincing.

MLS requires a coolant change to OAT as conventional coolants can affect the coating.

After nearly 500 000 km between two cars as well as the what the K midget has done, I have to say my own preference is for the original gasket. key thing is to check head hardness and liner protrusion. If either of these aren't up to the mark the repair is doomed.

Agree with Will about doing the cambelt. I crack the tension off the crank pulley before removing the head using a helper with car in top gear and foot firmly on the brake. Now that's one job that's easier to do than in the Midget!

If a VVC, check the rubber on the damper of the exhaust pulley. If it has fractured, replace it. Once the daamper starts folating rather than doing it's job it will stress the cam belt and lead to early failure.

And check all the hoses while they are easy to get at. the cars are of an age now that the hoses are approaching the end of their life, specially the ones taking the hot water away from the engine.
Paul Walbran

Thanks Paul and Paul

Kiwi Paul what do you believe is the benefit of fitting the original gasket rather than the multilayer upgrade. I find this unusual

Regards
Bob Turbo Midget England

>I don't see the point in the rail, the head bolts are still the same and the limiting factor in clamping load.

Paul,
that's right, but we've seen a lot of broken oil rails in the last few years. The only option to check it for creaks is to bolt it off.
So the new improved one can make sense at last.

Regards
Dieter
PS. now 145,000km on the clock with the very first gasket :) ... counting :)
Dieter

Bob

We sell both types of gasket to the trade here. The workshops who have had most to do with these engines are adamant that HGF is a response to a problem rather than a spontaneous event.

The most common causes they report are cooling system failure (for a variety of normal reasons) soft head and dropped liners. The latter two are usually a result of an earlier overheat. It's amazing just how many don't bother to check these basics are OK berfore replacing the head gasket. The amount of overheat needed is major rather than minor, sadly a lot of drivers seem to plough on regardless despite the needle being in the red.

These workshops do fit the multi layer gasket - but only because they are expected to, and have commented to me that they were quite happy with the original.

I'm certainly more than happy with the original on my own 3 vehicles. between them they have been given a lot of grief and a lot of miles without a problem in the gasket direction. We've just had the head off the 300000km one for a burnt valve (caused by a lambda sensor going lean while towing a B on a trailer) and checked the head hardness and liner height and all is fine.

Add to that the need to completely flush the original coolant out so it doesn't affect the new gasket and I'd rather take the easy way when I can't see any advantage.

Dave Andrews in a recent thread (K series Midget I think? but might be MGF) commented that his preference is for the original gasket too.


Dieter

Very interesting that, no reported problems here in that direction. i'd be interested to know the reason why. Some people get a knee-jerk reaction to apply more clamping torque to address a problem such as this. Witness cam bolts, over-tightened because of the torque relaxation issue, breaking. Bolts can only be tightend so much before there is a problem, ditto whatever they go into.

In the case of the ladder, if it hasn't been a problem on the original gasket why should it cause a problem on the replacement gasket with the bolts done to the same torque? Unless it's just old age and fatigue.

Maybe I've missed something, happy to learn new tricks if so!
Paul Walbran

PS: Bob - what symptoms make you think the gasket is failed - oil/water mix or something else? Oil/water mix always indicates a problem, most other symptoms also have other causes.

Paul Walbran

Sorry Paul missed your post

I have had a number of things occur lately. I had an hose blow, I have had a leak from my inlet manifold and whilst repairing that I changed the oil which on draining looked very chocolate coloured.

After a week I started using water by a couple of cup fulls a day and I had a lot of mayo on the dipstick. Non in the header tank but decided to do the headgasket.

Just finished putting the cleaned down head back on and torqued down. The internals of the engine were full of milky oil!!! so hopefully when I fully finish the job hopefully tomorrow I will be rid of the issue.
Robert (Bob) Midget Turbo

Well done Bob - the true grit of a working man!!

Me I get my man to do those things LOL

Seriously I hope it goes together OK.
Ted Newman

Thanks Ted

Believe me I came very close to finding a man myself.

Thought I would just like to see how difficult the job was.

Believe me it is not very easy at all, maybe if this works out OK and I now have a little experience I would find another one a little easier. That is if this is successful, I am far from confident however.
Robert (Bob) Midget Turbo

Bob - certainly the signs. A hose incident can trigger HGF. Hoses are getting to an age where they are failing, ~15 years for the early cars. I decided to replace all mine when I did the cambelt last time. Having made the decision, just in case I got lazy/rushed towards the end of the job I put a drill through them so I didn't have a choice!

The inlet gasket - yours is a non-VVC with the old black rubber gasket?
Paul Walbran

Hi Paul, think I had a problem before the hose event but who knows

My manifold is the plastic one and is using the green uprated type.

I have almost finished the job today and tomorrow I just need to fill with a cheap oil and water, put the plugs in and see if it works (fingers crossed)

I had a terrible job getting the new belt on. I bought a new belt and manual tensioner and needed ever bit of ability to get the belt on, I had nearly convinced myself it was the wrong belt but spent an hour on the net and phone making sure I had the correct one which I did

I am wondering if the automatic tensioner gives a bit more play when fitting the belt?

Ted meant to say I have sadly been on PAYE for many years so have had no opportunity to rob the country and keep a few quid stashed away for rainy days.

Ducking down low!!! Only kidding mate!

Was I reading somewhere the other day that companies in the FTSE 100 were paying very little tax?
Robert (Bob) Midget Turbo

Job done and 50 miles without water loss. Great, however fingers crossed for the next 30000 miles plus I hope.
Robert (Bob) Midget Turbo

Excellent info, ty all.

I have a 53000 mile 2001 British Racing Green Freestyle 1.8I, that ive just purchased.

Its due for its MOT in january, when i expect i will be very close to 60000 miles

Q1. It seems that the Cam Belt adjuster can be an auto or manual type, and it appears that i must remove to top cambelt cover to find out... since the engine number doesnt tell one that.

Q2.As the cam belt is due, i am considering if in january i should do the HG and water pump, and fit a coolant lever sensor..replace suspect looking hoses, new plugs, leads, as part of the 60,000 service, ie the whole bit in one go..

The coolant is the red OAT kind, and at the correct concentration.. ( checked with tube /float indicator )


The engine is ( fingers crossed ) without fault, no OBD codes showing, and the odd blat around the roads has given me no reason to question oil or coolant temperature, no spurious rises at any time.
Changing a head gasket on a fault free engine is preventative, but, i am of the belief, "if it works, dont fix it" and thats why i add this post and seek input.




N.J. Simon

I would be very suprised if your car was not an automatic adjuster so no probs

Anyway I think I would be tempted to just replace the cambelt, waterpump and adjuster.

You can buy these parts first because either adjuster will fit so long as it matches the belt you purchase.

So buy a belt and auto adjuster as a kit and all will be fine.

I personally would not change the headgasket simply for the sake of it but I can see the benefits.
Robert (Bob) Midget Turbo

Thanks Robert,

I think the same. Not least because though i have a
mechanic neighbour, who has just replaced the HG and a whole engine,in his garage at home, and like you folks, is very knowledgeable - the reason i chose to buy an MGF not a VVC or a TF as a commuter. I know that i will be doing the HG myself too.. to save paying labour costs..
But, i also know that i may miss something, despite attention to detail, and therefore risk not just loosing an engine without fault, but time and effort and parts cost.
So, i am going to buy a HG set, so ive got one stored safely, but not fit it till i sense a problem that will require its investigation.
Ive learned, that one of the easiest ways to ovehaul the engine ( like replace the HG ) is to drop the whole engine out from underneath.. thats how my neighbour was able to do the whole job in a weekend.

i am considering buying a Hamer four post car lift.

This, is because at 54, i am fed up of lying on my back with dirt in my face under a car... ive being doing that since i was a teenager... :)

I might make that a seperate topic.. if there isnt one here. The Hamer car lift, is manual, which is great if like me you dont have 16A electric availability at the garage...

not only will the cars chassis recieve better preservation, but dropping the engine out of the MGF will be , i think, a better practical solution..

I will look into that idea.. and integrate any feedback i collect here.
N.J. Simon

Hi N.J ? what do those initials stand for?

I am far from being an expert on the MGF or the K Series. But whilst I had a couple of offers to do the job for me I was keen to do it myself and find out more about the task.

I now know that short of changing the oil and filter everything can be done from either the driverside back wheel arch or from above.

Having now done the Headgasket change I would say it is not that difficult. The hardest part without any doubt is to fit the new belt, I had nearly convinced myself that the belt was too short and the wrong type. But in the end it fitted!!
Bob Turbo Midget England

N. is Nigel, J is James, and Simon.. well, its my surname :)

ive two other cars Rob, a triumph herald convertible on a limited mileage insurance.. full mot just passed, and another herald convertible in very good condition, all new parts and panels but in bits, into which - i have a complete rover SD1 vanden plas with tuned rover V8 3.9 230 BHP engine with weber edelbrock manifold, etc etc etc. i am in process of putting in that herald... its another reason the hamer lift interests me.

i know that info isnt to do with this topic.. so if anyone is curious how such a car as a herald could possibly take such an engine and live... i know. :) its a seperate topic ive created on another forum.

This is MG. so i am bouncing not only things i am doing, but questions i seek answers for.. that assist me with all three cars.. and its consequential that how one can do something on an MG might give one knowledge on other British based cars... :)





N.J. Simon

This thread was discussed between 15/10/2011 and 04/11/2011

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