Calling all duratec experts to the forum....

[fantombiker]

Hi, got an caterham r300 duratec. race car. The crank main seal was leaking oil, was fixed by good people. Next day it starts leaking again....Is there someway the duratec can build up high back pressure so the seal blows?.. or is there a trick to fixing the main seal?

[DCL]

Are we talking front or rear seal? Generally the Duratec is trouble free in this area as the rear seal comes preformed in a metal carrier that bolts to the block. The front is more conventional but up to the job.



The problem with replacing the rear seal is that it needs the sump removed to do it properly (to reseal the junction) and also, because of the size, I believe there's a tool to ensure the seal and felt dust cover are aligned without being folded over. In other words there's plenty of scope to get it wrong.

Edited by DCL on Sunday 27th September 19:11

[fantombiker]

Yes, its the rear seal where the problem is, I understood these to be a common issue on the Duratec?

[DCL]

If there's a series of failures, then there's a reason for it. As a builder, I know they need care fitting to make sure they are well sealed to the block with RTV sealant, centralised, and not damaged. If you do all that they won't fail on a healthy engine. If it is failing then I doubt pressure is the problem, unless your engine is not vented. It's more likely to be a faulty part, a bearing/crank problem, or poor fitting.

[edit] It is also possible that the leak is coming from somewhere other than the seal

Edited by DCL on Monday 28th September 11:09

[mic]

I've not had a problem with the rear seals, only time I know of one leaking is when the engine breather was blocked.

[sfaulds]

I've never known it on an R300 - certainly not a common problem.