Oil Filler Cap - Leaks

[ElliottN]

Recently had the head rebuilt. Ever since I have been battling oil leaks from the filler cap (3 eared type). I have it down to a just a trickle now at higher rev's - but can't cure it.

I have put in a new washer, tried a new(er!) cap, tried 2 washers (too tight to get cap on), cut a washer from thinner rubber to pack the main washer out (best result so far). I've thoroughly cleaned the cap to try and eliminate uneveness so the oil isn't leaking between the washer and the cap and I've even done just a little light filing to make sure the filler neck is "true".

Any experience or tips out there for curing such a problem?

It appears to me from inspecting the oil traces in the cap is it's not between the washer and the filler neck but around the washer, between it and the packing washer and or cap itself. Is there any recommended "non-permanent" sealant appropriate for sealing between the washer and the cap?

[ppnelan]

Elliot,

Sounds like you should try to address the cause of the problem, and not just the effect ! Perhaps the oil is not draining back to the sump well enough - I believe this is a common difficulty, especially on race engines. People often fit a breather in the front of the cambox to relieve the pressure that would otherwise force oil out of the cap & around the cambox studs. It could be that the cam bearings are too 'slack', resulting in too much oil 'leaking' past them into the cambox ? Or may be you have a high-pressure oil pump ?

The racing fraternity will no doubt provide some more helpful advice...

Regards,
Matthew

[type26owner]

Measure the distance between the bosses in the throat of the camcover and the outside distance of the clips on the cap. They only overlap by about 1/16". If the cap is not centered perfectly then it will tilt up on one side and leak. I made a cylindrical spacer which snaps into the cap to stop this problem. I'm afraid it's the only solution other than gluing on a spacer onto the camcover.

[marcfuller]

This might help - There is a neat little splash shield that fits underneath the filler cap, attaching to the cam carrier block studs. I got mine from Dave Bean for $5.95.

[type26owner]

The gasket must 1/8" thick. I bought a sheet of 70A neoprene to make the gasket from.

[types26/36]

Also gone through this problem, take off the cam cover and have a look from the inside if it is not centering and gripping both pegs (as Keith said)
Also the cam lobe throws oil directly up against the cap, I have made a thin alluminium plate to go over the cam lobe to act as a splash plate, you have to bend it to clear the cam and the cam cover and the last one I made to just clip in, prevous ones I made to bolt onto the cam studs.
I think one of the suppliers have these (Dave Bean I think)
Brian

[Emma-Knight]

with my S2 Elan camcover, it's important which way I fit the cap -
one or two ears forward. I know, it's not logical at all...

(also had the two seal stuff, three seal stuff and back to one now)
with two ears forward I might even have lost the cap!

[triumphelan]

I had the same leak found my cap only seals in one position ,so marked the cap/cam cover so it goes back in same position every time