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dreamin'
10th November 2012, 06:48 PM
When I park Dora (2.6 2a Dormobile) after a run, engine oil drips steadily from the gearbox crossmember area for a few minutes, then stops. Looks like to is coming from the flywheel housing drain hole, but not 100% sure.

Went for a long run today, long hills and windy roads (great day for it). When we got home the oil was running out in a thin stream for a while - maybe just hotter and more fluid than previous short trips.

The thing is, after a couple of hours driving like this, I couldn't measure any serious loss of oil on dipstick. If it had been leaking at a steady stream all the way it should have been down a couple of litres.

I'm thinking the oil is leaking into something that doesn't drain out til we stop.

Could this be the rear main seal leaking into the flywheel housing and, if so, is there any reason why the accumulated oil it would only flow out when stopped or out of gear?

Roger

Johnno1969
10th November 2012, 07:20 PM
Hey Roger,

I'm not really familiar with the 2.6, but my 2.25 has the drain hole on the forward-facing part of the bellhousing. Back when my mainseal leaked a bit (it doesn't now), a small amount of oil used to gather slowly in the bellhousing and then run forward out of the hole when I braked and stopped the vehicle. I didn't leave a steady trail of oil behind me - just a distinctive last-few-feet of drops wherever I stopped. It never showed any appreciable change on the dipstick as the volume leaking was so small.

Cheers,

John

dreamin'
10th November 2012, 08:45 PM
Thanks John

Same setup and exactly the same symptoms - we're onto something.

What eventually prompted you to replace the main seal? Can the clutch be affected by too much oil leaking through?

R

chazza
11th November 2012, 08:29 AM
Oil on the clutch will ruin it, so it is probably time to do something about the leak especially as the oil is getting on the road.

Unfortunately, it really means removing the engine to do it - the book says to leave the engine in place and remove the gearbox but I think it would be easier to put the engine on a stand and do the job in comfort. In any case, if the seal surface on the crankshaft is scored, the crankshaft will need to come out and be sent to an engine re-conditioner to be ground. Also a good time to check all of the bottom-end bearings and clean the sump etc.

Cheers Charlie

JDNSW
11th November 2012, 11:08 AM
First thing to do would be to make sure nit is engine oil not gearbox oil! Engine is more likely. Should be able to tell by colour and smell.

Oil on the clutch from a rear main seal is very unlikely, even with a bad leak, unless the wading plug is in place, as the leak is on the engine side of the flywheel.

Clutch contamination from a gearbox leak is more likely, but still not a high risk unless the wading plug is in.

John

dreamin'
11th November 2012, 11:49 AM
Thanks John

Definitely engine oil, wading plug is out.

I agree with Charlie this needs fixing, but heartened by the idea it might be able to wait til I have time and space to get the engine out to do it properly.

R

Johnno1969
11th November 2012, 06:53 PM
Thanks John

Same setup and exactly the same symptoms - we're onto something.

What eventually prompted you to replace the main seal? Can the clutch be affected by too much oil leaking through?

R


Hey Roger,

I fixed the mainseal leak only when I had to change the clutch (which didn't have anything to do with oil damage, incidentally). Truth to tell, I didn't actually replace the seal. The seal in there had done very little mileage and I had been super-careful when I installed it so had been a bit cross when it weeped (had thought I would defeat the notorious spilt-seal on the 2.25). So I took a risk and, rather than go through the agonies of replacing it, I did some deft work with some blue silicon and a butter knife. Worked a treat. Doesn't spill a drop now...

The others have already answered the question of oil leaks and the clutch. If the wading plug is not in place, oil from the mainseal should drain out safely away from the clutch. All the same, better not to have any oil anywhere in there....

Cheers,

John