Oil leak

[ceejayjay]

Hey guys

When I added edelbrock cover to my RV8 I lost the standard dip stick fastening. So I routed it through the manifold and screwed it to the framework under the exhaust outlets. So in attitude its no longer vertical but at about 30 dgrees from upright.

I know the adapters on the cover can leak but mine have been ok.

The Edelbrock breather loses vapour and v small amounts of oil discharge down the cover - which it should as its a breather!. It lead ( I Thought!! ) to a small spattering of oil drops on the leads.

Recently under torquey acceleration ( 4th on M ways for example ) I had that uh oh feeling as I noticed blue smoke in the mirror, - but it last a few seconds at best. Having gasped thinking a ring had goen etc, I thought it must be teh breather spitting out more than usual, but couldn't see why. Looked at the drips off the plugs onto the manifold and ist preety much under the dip stick cup where it fits onto the shaft. Question is - if the fitting is loose can oil surge up the pipe under acceleration ( when OP rises ) and thus is this likley to be the problem. No oil smoke from exhausts at any point so its not engine related in that way

Views??
Cheers
Chris

[craggle]

Can you post a picture of your engine Chris so I can get a better idea what you have.

One of the breathers should be connected through a PCV (positive crankcase vacuum) valve and connected to the carburetor or EFI plenum chamber. This will cause a slight vacuum in the engine and stop it blowing oil out of every orifice.

Craig.

[ceejayjay]

Craig

Right hand side ( driver side ) the breather goes into PCV valve on Weber 500
Breather left hand side is standard Edelbrock inverted cup shape with mesh holes around the perimeter. They've been like that for last 5000 miles without this hence why I'm thinking ist the dip stick
Cheers

[craggle]

I see what you mean now.

It's seems unlikely to me that oil would get all the way up the dipstick tube under the pressure of the crankcase. Is there an O-ring seal on the top of the dipstick tube?

Is there any baffles on the inside of the rocker covers to stop oil getting into the breathers?

If you have oil dripping onto the manifolds it would be a good idea to stop it. I have seen leaking rocker covers dripping oil onto manifolds and not just smoking. It was actually catching fire on the heat of the metal.

Craig.

[ceejayjay]

Baffles? Good question. They are standard chevy ones i guess with adapter plates. OP is great and engine runs like a dream. Agree a drip is one thing flames another!! Oh deep joy! Thanks Craig

[craggle]

I assume the dipstick used to screw to the side of the old rocker cover?
Is there any chance of drilling and tapping the adaptor plate to allow the dipstick to be mounted vertically again?

Craig.

[ceejayjay]

Beyond my ability levels!! But makes you wonder why it was vertical in the frist place. For a reason?? Probably. If I can be sure its the dipstick I will have someoen make that change for me
Cheers

[ceejayjay]

Been doing some deductive thinking. Can't be poorly baffled rocker covers or else they'd have been doing this all year. They are bog standard Edelbrock adpated for Rover. The adapter plates aren't and haven't been leaking. Anyway ist obviuos its the breather as a film of oil rudn down the side after a drive. Can't be piston rings wearing as the problem would be more mist/vapour than straight oil seepage. Checked both exhausts under throttle/load, no smoke at all. Power is fine, running is fine, OP fine - no changes detectable at all!

It happened suddenly so I'm thinking the crankcase pressure is building up because the PCV valve has packed up, or about too. Is that likely on a 7 year old Weber 500? If so, nay smart way I can tell, or should I just order a new one anyway. Struggling to think of another reason

[tosspot]

Chris,
I'll just stick my nose in on this one.
On my RV8 I started to get annoying little leaks, mostly from the inlet manifold gasket & after changing this twice decided to look at why this was happening.
As Craig said it is build up of crank case pressure which should be released through the breather via the flame trap on the RH rocker cover.
The original SU carbs were connected to the breather via a Y shaped tee, this was obviously adequate for the original instalation, but when I fitted a Holly carb I replaced this with 8mm copper tube connected to the air filter box. I replace this with 15mm tube & 'hey presto' no more oil leaks.
Hope this is of use,
Brian.

[ceejayjay]

Brian

Never sure which is RH & LH. Sitting in the driving seat its the LH bank giving me the problem. The breather cap is open to the air. On the RH the outlet goes straight to PCV valve. Breather has always let out a wee smidgen of oil - which is what it should do. The ste up has been like this for 15 months and 4,000 miles. Rings etc don't just go ( well they do but if thye'd gone I'd hear bits pinging down the exhauste with concomitant blue/white smoke ) and if it was worn rings it wouldn't suddenly spew. I can only think the PCV valve has gone or is working intermittently.

Cheers though