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Oil Leaks Again

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mylesw

Jedi Hopeful
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Hello

Thanks for all your advice on oil leaks a while back. I've finally got under the car and it seams that a fair chunk of the oil is coming out of the hole in the bottom of the bellhousing. I guess this points to the rear crankshaft seal. Now I'm not particularly keen to haul the engine out as I have my hands full with another project right now. Is there a quick fix I can do without hauling the engine out? At least then I won't leave a calling card on my friend's driveways each time I visit them...

Thanks for your help.

Myles
 
Hello Myles,

Sorry to inform you there is no quick fix, however all is not lost because you don't need to take out the engine. Just the gearbox. This is because you need to access the area behind the flywheel as that's where the oil will be coming from.

Basically the problem stems from age of everything and parts wearing as the get older. The original setup consisted of an area at the rear of the crankshaft that has a lefthand thread machined just behind the flange where the flywheel mounts. The purpose of this thread was to suck air back along the thread and thus forcing the oil back into the return tube that is screwed into the rear main bearing cap. The oil is there because it gets squeezed out of the rear (and front) of the rear main bearing and it cannot return through the drain either fast enough, or, the drain gets partially/fully blocked with sludge etc.

There is a kit to install a proper rear main seal but to do it the clutch/flywheel and rear engine plate need to come off after the gearbox has been removed of course.

Some people prefer to remove the engine but to do that you need help if you have never done it before (yes I know you can do it all yourself, it's just easier to have help). Also you need equipment that you may not have. To remove the gearbox you don't need any large equipment.

Once you get that far the rest is relatively easy.

I believe but am not 100% sure that the kit from Dennis Welch has a template to help you determine how much material has to be removed from the actual back plate for clearance for the sael assembly.

I'm sure that someone on this forum can probably tell you more than me because when I did it I built my own so mine is different to everyone else.

Don't despair it is something you can do yourself but if you have a good mechanic who you trust it's not as big a job as it seems, it just sounds a lot.

Anyhow not trying to scare you just trying to offer help and advice.

bundyrum.
 
Myles

You have the alternative of carrying a drip tray around with you :/- sorry about that.

The other cause of oil leak from the bell housing is the seal at the gear box end of the housing, but I am afraid that the main cause is most likely to be the rear end of the crank. Either way you will need to pull the gear box, and you may as well look at your driven plate in the clutch as well.

I have actually fitted the rear end conversion seal myself and mine was from SC Parts but they are all of a similar nature, if you go ahead I can give you some advice if required.

best of luck
Bob
 
Myles--

You might try running your car with the oil level closer on the dipstick to the "fill" line than the "full" line.
 
Hello Myles,

Engine oil is usually pretty dark after a few hundred miles whereas gearbox oil stays clean. Place a white piece of cardboard under your car after a run. Collected drops of clean oil would indicate gearbox leaks.

John
 
The interior will have to removed (easy about 30 minutes work unless you decide to heat shield the interior. Domino effect) to get to the gear box. Yes, the gear box comes out through the interior easily. The rear engine plate will have to be cut to make a larger opening for the seal and that is where you may need help. The kits come with a pattern. I took it to a welding shop and the cut it cheap and fast. The only tip is to drill the 4 holes deeper than the length of the screws or you will not get a good, tight seal. (And how do I know this?) Some will advise you to swap out the fly wheel for a lighter one (From Bill Boulton)and its a good time to check everything about the clutch.
TH
PS, watch that brass bush in the center of the shaft and if you replace it soak the in oil first.
 
Before doing that, I would want to be absolutely sure that the oil is not leaking out at the back of the valve cover and running down the back of the engine.
 
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