Engine oil leaks

[Styria]

Yes Sir, for many months now GB has been suffering from a variety of oil leaks, ranging from the Auto Trans area, to hydraulics in the area under the oil reservoir, plus engine oil leaks that seemed to be everywhere, and I mean everywhere. The hydraulic leak I eliminated, finally, by the installation of gaskets and rubber 'O' ring under the pressure regulator. Honestly, that took some doing as I have not been able to purchase a proper replacement part. So the fix had to be one of experimenting. Eventually, I had success, after a number of abortive attempts.

The engine oil leak was quite minor at first, but during the last fortnight when I have been using GB as a daily driver, the leaks became very disturbing, with noticeable drops emanating from everywhere, and the whole underside was a virtual mess. So, what to do, what was the cause,I mean 'is' the cause, and guesswork ranged from the front crankshaft seal, oil filter canister, rear main seal etc. etc. etc. - it was not nice. I must admit my biggest concern was a likely rear main seal failure. You know gearbox out, no engine and gearbox out etc. etc. - too horrible to contemplate. Anyhow, GB was due for an engine oil and filter change. Naturally, I implemented the procedures as outlined in my engine oil changing threads, and I also decided to degrease the underside of the engine. It was all nice and clean, and ready for action. After driving about thirty kilometers to my garage at home, oil drips became immediately obvious. I decided to leave well alone, and waited till next day at the workshop to again have a careful look at the source of the oil leak. I also, again degreased the underside.

By this time, I came to the 'educated' opinion there was oil seeping from between left hand head and engine block. Anyway, I cleaned the area properly, and applied some metal filler in between the slight recess that was between head and block. Ah ah, goody, goody, there was a good chance that this was the fix. Anyway, drove GB back home, and back to the shop the following morning, with further evidence of leaking oil. Okay, more looking, and looking. Eventually, I spotted a slight leak between the rocker cover and top of head.Okay, more degreasing and cleaning, and another small amount of Metal Filler and another trip home and back to the workshop. Jack up car, start looking and looking, and examining, and guess what ? That small area was the culprit, and whilst the 'fix' at the moment is temporary, it will became a relatively 'easy fix'in the end.

This is what happened. Oil leaking from the rocker cover gasket, running straight down on the head, forward motion when driving the car spread the oil along the 'crack' between head and block, also down to filter housing, along the middle of the alloy sump, all down the engine block and emanate as 'drips' from the rear main seal area. Boys and girls, now that I have found the source of the leak, and partially rectified the problem, all I have now is a slight seepage from that area. Good bye oil leak - let me tell you, just how satisfying is the feeling of success ! Will keep you posted on further developments. Regards Styria

 

[SEL_69L]

You did some top of engine work about a year or so ago.
I am thinking that perhaps the camshaft cover gasket may have been slightly out of alignment.

 

[Styria]

You did some top of engine work about a year or so ago.
I am thinking that perhaps the camshaft cover gasket may have been slightly out of alignment.

David, it was probably at the time I carried out the valve grind and de-coke that I refitted 'good' gaskets. For a long time I never had the type of oil leak that I experienced lately. One aspect to also watch out for are the domed rocker cover holding-down nuts. These can top-out, and I did have quite a problem of oil seepage past one of the nuts. It was a stubborn leak, but in the end a rubber 'O' ring and copper washer achieved the desired result and the leak stopped. In this instance, with the present situation, I will have to remove the rocker cover, and properly attend to the area that is prone to leakage. The metal filler I used is just a temporary fix. Regards Styria

 

[sean sherry]

Wurths have a very effective Hi Temp sealant , in a tube, that has proved itself on the common rocker cover leaks on the V6 Turbo Japanese engines. Replacing the gaskets is major surgery. They go hard with the excessive heat generated by the Turbos. This stuff works well in all sorts of places, especially on older Cars and Bikes where the original machining was not so accurate..
Sean

 

[Styria]

Sean, on the M100 6.9 engines, removal of the rocker covers is, at best, a so so job. A bit awkward, a bit time consuming, but not overly complex. I intensily dislike using Silastic, but will do so if there is no other suitable material on hand. I have used (just can't think of its name) that brown, real sticky stuff, but I am not always confident that it can do its job. You've also got to consider the two choices of that stuff (something called Aero...something - great use of the English language), one being the type that doesn't seal hard, and the other that becomes rock hard. It bears thinking about the (expensive) Wurth product. Regards Styria

 

[WGB]

On a more serious note, oil leaking from the cam covers can end up on the exhaust which was the case with my car when I first brought it home after purchase.
Apart from the smell there is probably a fire risk.

Bill