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MG MGB Technical - Timing chain cover oil seal

Dear all, advice needed.
What is the best method of preventing the crankshaft from moving so as to turn off the bolt? I do not think it has been removed for a good few years. The engine will be staying in the car!

/Moss

Moss

Moss,

I assume you don't have an impact wrench?

Some people may advise against it, but you can put breaker bar (and cheater pipe if need be) on it, get the end of the wrench or pipe on the ground (maybe with a block of wood under it) on the correct side of the engine, and then hit the starter. Don't sit there cranking it. It will be loose almost the instant you hit the starter.

Also, you can get a good wrench on it, stick the tranmission in 4th gear, wind the slack out of the drive train, have someone sit in it and hold the brakes, and then pull on the wrench, or smack the wrench with a good size hammer if need be.

Alternatively, you can take out a spark plug, get a piston near the top of the bore going in the right direction for the way you need to block the engine to turn the bolt, make sure it is on the stroke that has the valves closed, feed a bunch of soft rope (about 1/4 dia nylon rope works well), leave plenty hanging out the plug hole so you don't risk loosing it into the cylinder. Then since the rope won't compress you can turn the engine till it stops turning, and then loosen the bolt.

Actually, some people will advise against all these methods, including the impact wrench, but they all work.

Charley
C R Huff

I have a locking tool made from a piece of bent steel, which engages with the ringgear.

You need to remove the starter motor and then bolt the tool into place in order to lock the flywheel.

I fit it to the lower hole when loosening and the upper hole when tightening.


Dave O'Neill2

Thanks for response. The wrench and in fourth gear method sounds the easiest for me. Just have to order the parts...and post a few pics. I know I like looking at pics of what members are doing on their cars.

A merry Christmas to all

/Moss
Moss

Personally don't like "winding" the transmission up. Locking the fly wheel is best, but I have had success, odd times, with a heavy duty chain wrench on the front pulley. Depends when it was last moved!!!
Allan Reeling

Can't beat an impact wrench for this, IMHO....Worth borrowing, but working on cars without one is a real handicap....
They will work with almost any size compressor.
Removing the big nut on the business end of the tranny, is easy and quick with the same tool....(when you need to change the rear transmission seal)....
Edward
E.B. Wesson

More advice...thanks again. Have a question which will expose my total lack of knowledge and experience. But there we are.
What and how does an impact wrench work?
/Moss
Moss

Moss
Here's a link to one company that supplies them....
There are basically 3 types...Air, electric, and battery.
I have only used the type that you hook up to a compressor, and I know they work....
But many other types are sold, as you can see on this link.
Basically it's a rotating tool, that impacts the nut or bolt, while it turns....This results in very high torque, building up very quickly....
The first time you use the tool, it will pay for itself.
The amount of torque is adjustable, and I always start with a relatively low setting....
If that doesn't do it, I move a little higher....
Edward
Here's the link to a company that sells them..Just search impact wrench:

http://www.northerntool.com/shop/tools/category_power-tools%20impact-wrenches?cm_ven=google_PPC&cm_cat=PowerTools&cm_pla=core&cm_ite=impact%20wrench&mkwid=stCWmUx9Y&pcrid=15585435431&mt=e
E.B. Wesson

Now I understand - I've seen one on a air compressor being used with a wheel change at the garage-to take the nuts off and put on again at torque 60nm.

Thanks for the advice Edward
/Moss
Moss

I tried using my impact wrench on my kingpin top nut after my breaker bar failed to shift it. Impact wrench wouldn't touch it either, so I had to resort to a cutting disc.
Dave O'Neill2

Moss,

I know some people claim to be able to set a particular torque with an impact wrench (air gun), but I don't believe it myself. I don't allow tire shops to use them for replacing wheel lugs since there is a good chance for warped discs or ruined studs. I once found one tightened to over 250 ft lb.

If you decide to get a gun, one thing to consider is the length from front to back. Shorter will fit into more places.

As for your crank pully bolt, you might try just smacking a breaker bar with a big hammer without locking the engine. It could work.

Charley
C R Huff

"I once found one tightened to over 250 ft lb."

Ditto. They tightened the wheel nuts until the gun chattered, then used a torque wrench to check they weren't under-tightened! When I got home I broke my torque wrench trying to measure just how tight they were. When loosened most of the front nuts (which they did) had more play than the rear nuts (not done by them). Swapped front to back the nuts were loose there as well, and the rear nuts OK on the front studs, so I got away with replacing just the nuts, which were the V8 ones so not cheap. They had also raised the car with hydraulic platforms under the sills, the front being under the wings instead of the chassis/castle rails, so had bent the flange at the bottom of the wing which is only a cover panel and not structural. I complained in writing and got a very insulting response about how highly trained their operatives are, and how they can't be responsible for rot and deterioration in my car. I then went to Trading Standards but they didn't want to take it further. Very annoying.
PaulH Solihull

Paul- Sorry to hear the UK and USA share low standards and skills of auto repair. If you don't have it on video with a narrative documentation, many will weasle out of stepping up.On the other hand, good shops are like finding gold in a rubble pile. Well, at least you caught and corrected the over torgue before disaster. Cheers, Vic
vem myers

Some years back I took my Peugeot 505 in for new tires. I knew one of the lugs (the type with threaded hubs) was stripped and would not take full torque. I told the tire guy not to worry about it since I had plenty more at home. I had to bring the car back in a few minutes because the balance was off.

They gave it to someone else to redo. I was watching from an inconspicuous place when the new guy felt the lug break away. He looked around to see if anyone else had seen him. Deciding nobody had noticed, he finished up and they gave the car back to me without a word about it.

Charley
C R Huff

My wife's one-time next-door neighbour was a new apprentice at the local garage. At the end of one day he was given the job of putting the wheels back on a customer car before he went home. Wanting to get away early he put the wheels on the studs, the nuts in the hub-cap (which covered the nuts) and put the hub-caps back on the wheels planning to put them on properly next morning. Of course next morning the customer came for the car before he got there ...
PaulH Solihull

Not long ago, I came across a Dodge pickup truck sitting on the side of the road. Cars were passing him by as if he wasn't there. His left rear tire was on the other side of the road. Lying next to it was his brake drum. It seems that a tire shop had repaired the tire a few hours earlier, but had failed to tighten the lug nuts. They were no where to be found. He had no spare or jack, so I pulled the MG behind him, opened my trunk and handed him my scissors jack and instructed him to begin jacking up the rear axle of the truck. His drum brake backing plate was crushed, so I used a 3/8" extension and the hammer for my wire wheels to straighten it out. When I was able to refit the brake drum, I instructed him to remove a lug nut from each of the remaining wheels. I was able to get his rear wheel back on and held in place with the three lug nuts he had removed from the other wheels. He offered to pay me whatever I wanted, but I declined payment. A tow back to town would have cost him at least $100. I believe his first stop was at the tire shop that had repaired his tire. RAY
rjm RAY

Hello RAY, Are you sure it was a Dodge? I thought Chrysler products had left hand lugs on one side and right hand on the other. Is that just old stuff from the pre-70s or so?

Moss, getting back to the original post, did you get the crank bolt loose yet, and if so, which method did you use?

Charley
C R Huff

I thought it was only for a short period after the change from centre-lock because they either didn't believe or didn't know that non-concentric studs didn't have the same loosening tightening effect.
PaulH Solihull

Paul,

I don't know when Chrysler ended the center locks, and I don't know if or when they discontinued the left / right lugs. But, I'm pretty sure that they were still left/right in the 60s and 70s. I haven't had anything to do with any of them newer than that.

I bet we have some Mopar person on here who will set us straight before long.

Charley
C R Huff

Update - I'm still waiting for my 1 inch and 5/16 socket to arrive! Should be anyday soon! Bought on e-bay. While I'm at it I also bought a pair of HIF4 SU carbs. Decided to convert from a weber 32/36. My engine is a 846F specification British. Any suggestions on the best way of cleaning them?

/Moss


Moss

I use cellulose thinners and a brush to clean them externally first. Then dismantle and clean every piece individually. This gets them really clean.
Iain MacKintosh

Carb cleaner! In an aerosol it's high pressure and is very effective at blasting muck off.
PaulH Solihull

Hi Moss,

Back to the crank bolt.

I use the rope trick, but a couple of precautions.
Make sure that the cylinder you use is on its compression stroke, so the valves are closed, otherwise you could bend them. Use a lot of rope to keep the piston down the cylinder, as it moves up there is more rotational movement for relatively little upwards movement.

I find that putting the transmission into gear, and braking doesn't work, for me, as by the time I've wound up the slack in the transmission, I've run out of swing round for the spanner.

Good luck..
Herb
Herb Adler

Chrysler stopped using left handed studs in the mid '70s. An impact wrench, whether it's air or electric powered, uses the hammer and anvil system to create torque. They utilize either one or two hammer and anvil mechanisms depending on the price and complexity of the individual gun. RAY
rjm RAY

Just taking off the bolt seems very daunting. My thoughts at the moment is to try taking off with the airgun then put back on by hand using my torque wrench.
We are talking about 95nm so cannot be that difficult - but then I do not know when it was last taken off. Then on further thought could the problem of leaking oil around the timing chain cover be the oil seal - could it be coming from somewhere else? I've checked all around the engine and cannot find any other places where it could come from...
/Moss
Moss

How did you check it? Clean oil can be difficult to see, I've seen recommendations to puff talc around suspect sources which makes it much easier. It needs to be clean and dry first though.
PaulH Solihull

It is more likely to be the lip seal, they do wear. AND they do wear a recess in the crank. Plus they are seldom centralised when installed, leading to premature wear.
If you get no joy with a chain wrench on the pulley or an impact wrench, take the starter motor off and lock the fly wheel. None of these methods is likely to do any damage.
Allan Reeling

In defense (evidently needed), of impact wrenches....Good ones (like my Ingersol-Rand), DO , most definitely have adjustable torque....
When the wrench is used by a competent and careful person, there is no reason for it to damage anything....
Remember, "guns don't kill people, people kill people"...
and the same thing goes for impact wrenches...Even a good tool, in the hands of an idiot, is dangerous.
Edward
E.B. Wesson

There is so much oil that the cross memember underneath chain cover is covered with oil - wipe the oil away, but appears again after a few runs. I'll take a pic...

/Moss
Moss

Moss,

Do you have coin operated car washes there (with the hand held wand) and are they equipped to allow hosing off greasy engines? If so, that would clean it up for inspection.

Charley
C R Huff

Hi Charley, no, not in the winter - minus temperatures. In fact the rest of the engine is very clean - it is a 'new - from 2008' engine from Ivor Searle in the UK. Good compression...wait a sec - could this be the problem. When I got the car in 2010 I was confused as to how much oil to put in - 3.4 liters or 4 litres or 4.2 litres. I could not find an exact specification for the 846F engine specification and read somewhere that at some point the quantity of oil required was reduced. I decided to to put just under 4 litres (no oil cooler at the front). The point being have I 'blown' the seal in the timing chain cover? But then the oil pressure on the gauge has and is always consistent. No signs of contamination in the coolant - changed it recently. I'll take a pic tommorow...

/Moss
Moss

Moss,

I think I recall that you have a rubber bumper car. I have a 77 roadster, and was surprised by how little oil it took to fill it up. I don't remember exactly, but it was less than 4 quarts. However, I don't think a little too much oil would blow the seal out. Perhaps if the crankcase ventilation system were not correct you might blow out a seal.

Also, the oil pressure on the gauge shouldn't have an effect on the front seal since the pumped pressure is not presented to the seal. And, blowing the seal would have no effect on the pressure observed on the gauge. Actually, the oil pressure on your gauge is hardly more related to the timing cover seal than is the air pressure in your tires. You might be confusing oil pressure (good) with crankcase pressure (bad).

Charley
C R Huff

The crankcase has two ports to the outside - the suction port from the carbs and the fresh-air inlet. Both would have to be blocked, or you would need a lot of blow-by.

As for volume the Drivers Glovebox Handbook AKD 7598 4th edition states:

18GG, GD (no oil cooler) 7.75 Imperial pints (4.26 litres, 9 US pints)
18GG, GD with oil cooler 8.25 Imperial pints (4.5 litres, 9.6 US pints)
18V engines (no oil cooler) 5.25 Imperial pints (3 litres, 6.3 US pints)
18V with oil cooler 6 Imperial pints (3.4 litres, 7.25 US pints)

So 4 litres for an 18V without oil cooler is 30% too much, and too much can cause a problem. Did the engine not come with a dipstick?
PaulH Solihull

Moss The oil pressure is not a reading of crankcase pressure. As Paul said for the crakcase to pressurise, the rocker cover breather (non standard cap maybe?) and the side cover vent would need to be blocked. Even then the pressure would blow the dip stick (have you got one?) up. Not sure how much extra oil is necessary to swamp the crankshaft seals. But if the front seal is leaking due to pressure then one would think the rear would also suffer. This would show as a drip from the weep hole on the bottom of the bell housing, and maybe a clutch judder.
Allan Reeling

Thanks for response.
1: From your advice Paul I have put too much oil in the engine. Fortunately I have not driven very much. Last season just 400 miles and not very long trips. Yes of course there is a dipstick but the problem is, as far as I understand the type does not match the specification of the engine (18V 846F) I have looked at parts catalogues and the dipstick should be straight (MGOC part number 144 18V onward - there are two other types part number 140, which I have, and 143. Moss also have two types - straight from 1972 onwards and one which is bent for 1968 to 1972). The one I have has the bend according to above, apparantly this matches an earlier engine type ie. 4 litres. I know my engine information is correct as I contacted Ivor Searle and was told when the engine was reconditioned (March 2008 unleaded) and the specification ie18V 846F (non overdrive). So the problem could be that I have relied on the dipstick - which on refelction is rather silly, instead of the engine specification. Unless the type of dipstick - straight or bent does not matter ie max level is max level and the same amount when measured by the dipstick regardless of the type. At the risk of being called an idiot I have to confess that with 4 litres of oil the level is over the max mark but because of dipstick confusion I have thought 3 litres cannot be enough - the engine did sound more 'tinny' (it is an issue I have investigated before - and to save face a bit I did speak to an mg specialist here in DK- He told be 4 litres should be alright!!!! apparantly not)
2:Allan, the crankcase breathing is not blocked. No oil from the gearbox - just slight dripping from the front (I have newspaper under the engine to pick up oil stains).

/Moss
Moss

At the risk of stating the obvious. This started with the question of how to remove the crankshaft bolt. How bad is the oil leak? Mine drips-they all drip. Is the effort worth it?

Dipstick /oil level. Can you push a piece of wire coathanger down the dipstick hole till it rests on the sump bottom. Measure depth of oil. Someone on here is bound to know or could measure for a 18V engine. Cut new mark(s) in existing dip stick to suit.
Michael Beswick

There were three sticks, three dipstick tubes, and three sumps. But they didn't all change at the same times so there are actually five different combinations, from the parts catalogues. However the dates and change points in that don't line up with the capacities given in the drivers handbook!

The other thing is that the capacities quoted refer to a dry engine, so slightly less will be needed for an oil change, although having an oil cooler will probably make more of a difference than without.
PaulH Solihull

Now received my socket so ready to go. Here is a pic. You can just see the crossmember glistning underneath and around the cover.
One question; I'm thinking of trying the impact tool and socket method first.What could be the possible damage to engine if it turns too much in anti-clock direction?

/Moss


Moss

Moss,

I'm not aware of any damage caused by turning backwards. I have backed them up and then brought them forwards again when passing the point to adjust valves or points. You may want to wait to see if others disagree.

However, I suspect it will not be an issue with an impact wrench anyway because it will be off before the engine ever turns anyway.

Charley
C R Huff

"What could be the possible damage to engine if it turns too much in anti-clock direction?"

Nothing, you cannot turn a standard MGB engine 'too much' in the reverse direction. But as Charley says an impact wrench is very unlikely to turn the engine, even if the nut doesn't immediately come undone. There is far more resistance to turning than an F1 road wheel for example.
PaulH Solihull

That's good then. So in 4th gear, on with the breaks and the air driven gun with the impact socket should do the trick!
/Moss
Moss

Moss, you don't need to put your car in gear as the impact wrench will not turn the engine. Make sure you buy a proper impact socket.
regards John
john wright

Sometimes works, but as i said "it depends", didn't work for me. Locked flywheel and long knuckle bar may still be necessary, it's guaranteed!!. For the sake of a few bolts and nuts and a short piece of angle why bother with all the other "maybe's".
Allan Reeling

Hi Allan

For me, locking the flywheel is the prefered method.

Ronnie
RA Potter

I've always felt that locking the flywheel is a good idea, but only if you have the proper tool. If you jury rig something to hold it, I think you risk chipping or breaking a ring gear tooth.

Charley
C R Huff

As mentioned, with an impact wrench, you will not need to lock anything...In fact it would probably be a good idea not to....That bolt will be out in a few seconds (IMHO).
PS
Don't try using a universal between the extension and the socket, and be sure and get a good bite on the bolt head before pressing the trigger.
Edward
E.B. Wesson

Well, I've started the job - first problem - not enough room for the air 'gun' with the radiator in place so will have to take it off today....

/Moss
Moss

It worked with the air 'gun' impact socket. Very very easy. No brakes applied or in gear. Very useful tool.
I suspect the oil leak has occured because of a bad seal on the gasket at the bottom of the timing chain cover. Perhaps I knocked the cover 'out of place' (who knows) last January 2012, when I took the engine/gearbox out.
Anyway first part of the task done.
/Moss
Moss

Here are two pics - timing chain cover which looks quite new in fact. One can see a deposit of oil behind the gasket on the cover side, at the bottom - the cover is upside down. It is here that I suspect the oil has been seeping out. And a pic of the engine front showing crank- and cam shaft cogs, chain and oil-thrower. Also here everything looks quite new.

/Moss



Moss

The pic of the cover.


Moss

Oh no! We are going to have to go through what MoWoG means ...
PaulH Solihull

Moss
Congratulations for getting the bolt out and cover off...
I am sorry that you had to pull the radiator...
I would have thought that you could have run a long extension through the crank hole, and put the socket on, after the extension came through ...
The good news is you did it...
Your timing gears, chain, and tensioner , look really good....
Use a good sealant on the new cover gasket, and a modern oil seal, like the ones sold by Moss Motors....
Tighten the cover by alternating bolts, from one side to the other, so as not to distort the cover.
Edward
Edward Wesson 52TD

Oops!...Wrong car! (was thinking you had a "T", instead of a "B"...Too much coffee!
Anyway, I am surprised that you couldn't get on it with an extension from under the car...
Edward
Edward Wesson 52TD

"Oh no! We are going to have to go through what MoWoG means ..."

What does it mean?

I had a Triumph Spitfire in the 60's and eventually worked out what 'Stanpart' meant.
Brian Shaw

There are differing opinions, but from my research it came from the amalgamation of Morris, Wolseley and MG in the 1930s. Before that Morris Motors Ltd. was a publicly quoted company but Lord Nuffied owned Wolseley and MG personally until he sold them to Morris Motors. The design office at Abingdon was closed down and they lost their autonomy to design many parts including the power train, and had to use stuff from the Morris Motors parts bin instead, along with Wolseley. MoWoG was cast and pressed into many components, and takes the first two letters from Morris and Wolseley, and the G from MG. They could have used the M i.e. MoWoM but MG chassis numbers had to begin with 'G' as 'M' was already used for Morris, and made the same change to this identifier.
PaulH Solihull

Moss when you install the front cover and new gasket, tighten the screws up with the pulley in place. Put the screws in a couple of turns, then oil the lip seal and pulley and merely push it in place, before you start to tighten said screws. That will properly centralise the lip seal on the pulley.
Allan Reeling

My threads always seem to generate comments and advice - thanks to all. Now I have a conundrum. The oil thrower has a notch on the edge to make sure that it fits over the woodruff key. However, the thrower can be pushed passed the key and just spin round. Is this normal?

/Moss
Moss

no probs. It's clamped.
Allan Reeling

Ah yes, of course Allan, clamped by the pulley...had not thought of that.
Another thing I've just noticed is that there is a dark cream like substance inside the cover - you can see on the pic to the left hand side. It looks and feels like mayo. But the oil around the area is clean - still dark green (bought from Halfords in the summer when I was over in the UK). The coolant is also clean as in a clear dark blue. Has this been caused by condensation?

/Moss
Moss

'Mayo' is indeed caused by condensation, from inadequate crankcase ventilation. All but the earliest MGBs had positive crankcase ventilation, via a PCV valve on the inlet manifold from Feb 64, then via suction ports on the carbs for 69 models on. These both provided the suction on the engine side cover, with a filtered and restricted fresh air inlet in the oil filler cap, or via the charcoal canister on cars so equipped. That does make scavenging of the front cover pretty limited, I would have thought, unless you get the engine good and hot on a regular basis.

The oil thrower faces (concave i.e. cupped side) towards the engine on early double-row timing chain engines, away on later single row engines.
PaulH Solihull

Moss,
Is the oil filler cap the usual black plastic effort with a mesh internal?
Allan Reeling

Thanks for reponse gentlemen. In response to Paul comments - the oil thrower is on the wrong way then - I have the single chain and the concave is towards the engine. Re Allan's question, the oil filler cap is a chrome one with a hole in the top - no mesh or valve inside. I have a KN breather filter on the crankcase breathing pipe. All the American smog kit was removed - my spring job is going to be installing the used HIF4 SU carbs I've bought and therefore a original breathing system UK spec. I just cannot seem to fathom out the Weber. It also looks ugly plonked on the side of the engine. The other detail is that I do not drive the car very often (off the road between November and March due to insurance requirements). So the problem could well be quite simple ie the car does not drive often enough - hence a build up of moisture...
Still waiting for my new gasket and new seal in the post!

/Moss
Moss

Moss, I rather suspect your crankcase is short of ventilation, which will be greatly helped when you install the SU's and connect them to the crankcase breather pipe. Then evapourated water will be drawn out instead of just being swished about by the piston movement and then condensing as the engine cools....................mayo!
Allan Reeling

Paul-
I take it that when you refer to the early oil thrower that is installed with its rim facing outward (BMC Part # 12H 775), you're referring to the one used on the three-main-bearing engine. This was done so that the rim would project outwards over the felt oil seal in the timing cover and thus prevent leakage. All of the five-main-bearing engines used the other oil thrower (BMC Part # 12H 740) that was installed with its rim projecting inwards in order to provide better lubrication of the camshaft drive chain.
Stephen Strange

This thread was discussed between 22/12/2012 and 16/02/2013

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