oil leaking between rear of sump and bellhousing

[crankshaft77]

Hi guys.bled my brakes and reversed the car 100 yards up a hill to test the brakes.job done put the moggy in the garage and noticed a oil leak coming from the back of the sump and dripping of the bottom of the bell housing i,d say its every 5seconds its engine oil that i know.would this be the crankshaft oil seal?and is this an engine out repair?

[aupickup]

could be a breathing prob with the engine

[les]

You may get away with replacing the sump rear cork seal, after sump removal, of course. Renew all sump gaskets while off. I removed the flywheel and backplate, to renew that gasket as well but probably didn't need to. Engine out for that though.

[bmcecosse]

If between sump and backplate - then that is sump gasket/cork seal problem - which is easily attended to. Drips from bell housing are the rear seal - but there is no real seal there - just a scroll and labyrinth. And as mentioned above - excessive crankcase pressure will be the problem. Clean the breathers and make sure the connecting pipes are clear. With a hot engine, idling - remove the oil filler cap and rev up - is there a plume of smoke/fume?

[crankshaft77]

Thanks guys.when you say check and clean breathers do you mean air filter?

[bmcecosse]

No - the breather pipes .... on rocker cover and cam follower chest cover......

[crankshaft77]

Thanks i,ll check these out first.

[crankshaft77]

I don,t have a breather on my rocker cover.but theres one on the side of the engine!

[bmcecosse]

Well - there's a possible reason..... Have you done the smoke/fume test ?

[crankshaft77]

Its the first thing i,ll do tomorow evening after work and i,ll report back!

[crankshaft77]

Done the smoke/fume test not alot of smoke when i done it the fumes seem to be coming out of the breather pipe on side of head which prob is normal? I right now have the sump of and notice that there is no cork gaskets on front or back of the sump just the two paper halfs each side! Am i right in saying that the two cork bits go over the half moon bits each end?

[crankshaft77]

Correction the two cork gaskets are present think this could be the problem ok think oil could have been escaping on the back end!

[bmcecosse]

If between sump and backplate - then yes it is cork problem.

[crankshaft77]

Well new sump gasket on new end seals on and still leaking! I have to say that i wasn,t impressed at all with the new cork end seals as when i put them in there slots they looked very narrow trying to get them to sit right isn,t easy also.disappointed i have to say..
Any ideas chaps?

[philstill]

Are your big end and main bearings in good shape? Wear in this department can cause the crankshaft to run on the oil thrower cover causing wear, ( arrowed in picture ) thus allowing oil to run past, it should be smooth on the inner side. It is held on by 3 x 1/4 bolts. You will have to remove this to inspect and it will be obvious if the crank has been running on it, there will be grooves present. There should normally be a 3 thou gap so the crank shouldn't touch it. Unfortunately the engine will have to be removed to do this. I'm not saying this is your problem, just a possibility. I've come across this fault many times with different Minors I've restored for customers in the in the past. Another possibility is that the oil pump gasket might need changing.[frame][/frame]

[crankshaft77]

Would,nt have a clue if the big end are bearings are worn.just learning as i go mostly the hard way lol . Don,t really want to take the engine out until i,m sure thats what needs to be done.

[bmcecosse]

Are you sure you put the cork seals in the slots RIGHT WAY ROUND ?? They are generally a very snug fit in the slot...

[les]

---and usually need some trimming off the length, so they sit about 1/8'' above the sump flange. If you leave them too long it prevents the sump pulling up tight onto the engine block.

[crankshaft77]

Well to be 100% honest i,m starting to think that i,ve done just that.If you can picture them sitting flat i looked at them and thought they look too broad to fit in like that so i turned them side ways and put them into there slots and there was room on each side.believing that when i tightened the sump the seals would press down and fill the void !

[crankshaft77]

Right thats another job complete no more leak put another new sump gasket on from bullmotif better fitting end seals than the last some instant gasket and the jobs a good one.Many thanks for all the replys..