Oil leak on EC300 expansion pipe

[eff]

Originally Posted by GMP

You will wad up any pipe good before you break spigot bolts on a steel spigot.

About o-rings: Silicone hi-temp orings have poor abrasion resistance. Ever notice how they are worn flat from vibration and pipe movement? Buna N (common black rubber compound) is better but less heat resistant, and tends to retain its compressed shape. Viton is good but also not too abrasion resistant. I buy a big bag of Buna N o-rings and change them if I notice a leak. Its not a big deal.

Glenn, what size Buna N rings do you get? I think I'll order some from McMaster because I'm leaking now too.

[PEB]

I just got 50 Buna N o-rings from MCCaster Carr to my door for $15. I ordered the 44mm x 3mm, which believe is the correct size.

Paul B

[colinmc400]

Orings are no bother cause we use heaps of different ones at work, including some fancy James Walker hi-temp ones. I 'll suggest the tech trys one of those.

Cheers

[iancp5]

Originally Posted by GMP

You will wad up any pipe good before you break spigot bolts on a steel spigot.

Maybe but I've had such a bad time with exhaust studs made of cheese on road bikes I get nervous! I seem to just have to tlook at them to shear them off.

[GMP]

44mm x 3mm is the size. Viton is listed in the '07 parts book but my bike came with the hi-temp silicone as before.

I work in a research center, we have the best of everything here. viton, silicone, teflon, Buna N and more. Do the research, even Mcmaster has a material/application guideline in their on-line catalog. Ideally, you need heat, petroleum, and abrasion resistance. You can't get a compound that is good at all three. If leaks are a persistant problem check the pipe header/flange for misalignment/bending. When you remove the pipe, take a close look at the o-rings. It will be obvious if uneven pressure is applied siide loading the seal, as they will be compressed/worn flat in that area. Also, if your pipe vibrates more than normal, from a bad mount, springs, etc., the excessive movement of the flange will wear the o-rings faster.

Try the silicone with new o-rings. Just get everything squeaky clean first for a good bond.