Rocker box oil leak issue 3.0

[alec.m]

I had a new gasket fitted about a year ago but have a leak again which is dripping onto the exhaust. Am I just unlucky and had a bad gasket or might there be an issue with the crankcase - ventilation/oil separator system causing pressure in the system. Has anyone had this issue? Is there any part of the ventilation system that gets blocked and is it accessible without stripping loads of stuff off? Thoughts and advice gratefully received. On the plus side it passed its MOT this morning.

 

[mrscalex]

Can't speak from experience but taking a think.

Even if there is an issue with your CCV you wouldn't expect it to pressurise that area such it forced oil out unless there was a poorly sealing area on the gasket.

My punt is it wasn't fitted properly or the gasket is faulty. Are you sure it's coming from the valve cover? Not that there's much else to leak on that side of things.

 

[colb]

Didn't last long did it, when you changed the main gasket were the round rubber seals under the cover securing bolts replaced, they should be replaced as they go hard with age and can fail to compress the main gasket enough. Since its leaking onto the exhaust again check exactley where the leak is, gasket sealant needs to be used around the half moon shapes at front and back of the cover but rest should be ok without sealant, the gasket should seal ok. Check out the CCV hoses are not furred up with gunk, replace if any are found in bad condition.

 

[mrscalex]

Didn't last long did it, when you changed the main gasket were the round rubber seals under the cover securing bolts replaced, they should be replaced as they go hard with age and can fail to compress the main gasket enough. Since its leaking onto the exhaust again check exactley where the leak is, gasket sealant needs to be used around the half moon shapes at front and back of the cover but rest should be ok without sealant, the gasket should seal ok. Check out the CCV hoses are not furred up with gunk, replace if any are found in bad condition.

Agree with what you're saying about the gasket. But on an M54 it's not really practical to check all the CCV hoses without removing them, then you might as well replace them anyway.

 

[alec.m]

Can't speak from experience but taking a think.

Even if there is an issue with your CCV you wouldn't expect it to pressurise that area such it forced oil out unless there was a poorly sealing area on the gasket.

My punt is it wasn't fitted properly or the gasket is faulty. Are you sure it's coming from the valve cover? Not that there's much else to leak on that side of things.

I agree, there`s nothing else oil related in that area at the rear of the head.

 

[alec.m]

Didn't last long did it, when you changed the main gasket were the round rubber seals under the cover securing bolts replaced, they should be replaced as they go hard with age and can fail to compress the main gasket enough. Since its leaking onto the exhaust again check exactley where the leak is, gasket sealant needs to be used around the half moon shapes at front and back of the cover but rest should be ok without sealant, the gasket should seal ok. Check out the CCV hoses are not furred up with gunk, replace if any are found in bad condition.

Unfortunately I have arthritis in my finger joints and now have to pay someone to do work on my car but the mechanic I use I trust. I will mention your comments about the sealant in those places to him. Unfortunately it`s about the worst place to be able to see exactly where it`s leaking from.

 

[t-tony]

You can buy inexpensive endoscopes on eBay which run through an App on your phone. I tape mine to a thick bit of wire (coat hanger) and then you can use it to “look” around the engine where your eyes can’t by watching it on your phone screen.

Tony.