The cam feed pipe is at the rear of the engine and would probably leak onto the transmission bell housing if it is leaking form one of the top banjo bolts. From what you describe, I still suspect the oil canister seal.
I guess in theory it could also be a bad gasket between the filter housing and the block, but if you are seeing oil on the bottom of the housing close to the canister that might not be it either. Has the engine been apart recently?
It may be worth you while to pull the canister and check to see if the seal isnāt twisted or broken. They can be a pain if they are not installed properly or if you tried turning the canister once it is seated.
If you are going to pull the canister, you may want to re-torque the bolts that mount the filter housing to the block.
Good luck. I know how frustrating these things can be.
I just thought of something else, If you say the bottom of the canister is wet, you may have a bad oil sealing ring on the bolt that holds holds the canister. It is a rubber ring that fits between the head of the bolt and the oil canister. If that is gone then no mater how tight the bolt is, it will still leak. Looks like youāre going to have to pull the filter canister either way.
I only once placed a new seal onto an old one. It was the first oil change I performed on my car, after about a week I was traveling down country and about an hour into the trip I noticed the OP dropped. Cost me an engine tear down and crank rebuild as later on a bearing let go and I drove it home. Much to the disgust of my eldest (British army REME trained) mechanic brother.
It is the newer design that does feed from the oil filter housing and not via the rear main bearing. The bolt area doesnāt look as if it were leaking. Is the relief valve before or after the filter?
I wasnāt aware of that one - but which would it be in the pic (1C 06L) above in my first posting? The oil filter base only has the gasket to the block EAC.1542 and the canister 11663 is sealed against the base with the large rubber ring 11670. So the only āway outā would be around the main bolt going through the top of the canister which is sealed by 11667 and 11668. At least it didnāt look wet from the outside of the canister.
So indeed, maybe for whatever reason, the rubber ring has torn. So, yes, time for an oil and filter change ā¦
One more question: In the parts catalogue (1C 06L) there are two different bases for the canister. The one depicted left sports a blind bolt (C.44947) blocking the big hole on top of the base. The one depicted right does not. On my car there is no such plug.
My engine is 8L 13683 no A/C no oil cooler (only police cars had oil coolers) not CDN/J/USA . How do you read the instructions? Iād say that from 8L 9781 on all non A/C not CDN/J/USA cars should have the left assembly with the bolt in. Can I have lost that plug?
Iām not familiar with the housing on the left in your illustration. It look like it has a fitting for a capillary pressure gauge. It is more likely that they did away with the plug that you see in the right illustration. I seriously doubt it would be something that significant. If it were you would see an oil stream while the engine is running and you would rather quickly run out of oil. The canister seal, on the other hand could have a small but steady leak under pressure that might not be that noticeable. When you shit the engine down and the oil is still somewhat warm, the canister would empty over time. maybe an hour or two or more. And yes, never over tighten. Refer to a manual for correct torque.
Iāll never forget the one and only time I put in a canister seal incorrectly. It was on a MKII and I knew right away there was a problem once the engine was run as there was a huge puddle forming under the car. Never did that again. Just like I never again left out a drain plug during an XJ6 oil change. We can only hope to learn from our embarrassing mistakes.
just returned from an explorative excursion to the car, son and me, two sources of light and his GoPro. Put some light on from the engine bay and underneath, the GoPro shooting from underneath, me peeking in from top through the intake side and him starting the engine:
I havenāt even checked the vid footage yet as it was so obvious from my viewpoint that a big stream of black filter oil was pressed out all around the top sealing edge of the canister - probably the same underneath - just after the engine started.
So, one easy way out: the rubber seal at the canister has broken and only needs replacement. But, why would it give after only two years of service and no change from outside whatsoever?
The bigger issue might be that the inside pressure of the oil filter canister has risen dramatically during cold starts. In such situations the relief valve should open the circuit at some 60 lbs. Could it be that a failure of the relief valve exposes the canister to a much higher pressure than it is designed for? Any other ideas welcome!
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The function of the relief valve is indeed to avoid excessive oil pressure, Jochen - which otherwise would occur in a cold climate with cold, and/or high viscosity, oil.
In principle; the oil pressure gauge should reveal such a situation. But even with excessive oil pressure, there shouldnāt be any leaks from the filter - unless something is wrong with the sealā¦?
Another point is that clogged/faulty filter would also raise oil pressure - again relieved by the relief valve. As far as I recall; the oil pressure sensor picks up pressure after the filter - which may mask a failed relief valve.
The point is that oil pressure gauge generally shows the overall pressures within the engine - oil deliberately leaks out from the lubrication points to ensure circulation, thus reducing pressureā¦
As an aside, as the relief valve opens, dumping oil back into the sump - thus reducing oil flow through the engineā¦
fortunately, it is not the central bolt that leaks (sealed by parts 11665 and 11668), but the full sealant length of the main gasket 11670 which comes with the filter cartridge. Iāll see the car to an oil and filter change and check whether the relief valve JS234 needs replacement.
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You do not mentions specifically the thin sealing ring fitted inside the groove in the filter housing, Jochenā¦?
The seal fitted to the cartridge is insufficient, but if the housing leaks with that seal in place - somehow the housing/cartridge may be damaged/askewā¦?
Ahm ā¦ 11670 is the thin sealing ring that is fitted inside the goove, isnāt it?
But your advice on the canister is well-taken. After all, there is no apparent reason why that sealing ring that was replaced two years ago and leads a peaceful live in its groove should brake out of the blue.
Next week Iāll get at it, make an oil and filter change - just ordered the oil and the copper ring for the sump bolt - and have a close look at the gasket and the housing.
My sad feeling though is that the pricey relief valve is stuck and doesnāt relieve when itās supposed to. Is there a chance of reviving its function?
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The relief valve is exceedingly simple, Jochenā¦
Itās basically just a plunger with a spring - oil pressure moves the plunger against the spring, and moved enough; it bleeds off pressure to the sump. It can be cleaned and tested for function - and can even be adjusted by using washers to tense up the springā¦
The plunger may be frozen shut and/or the drain clogged. But it should up with excessive reading on the pressure gauge. Nominally the relief valve is only active with oil cold and thick. And I āthinkā that the filter seals should hold, if intact, against anything the pump can deliverā¦?
Thanks, Frank,
that is exactly what I wanted to know! The scenario you described is exactly my problem: right upon startup of the cold engine (not when warm) thick black oil is pressed out along the canister to filter head seal. This stops after a few seconds.
So I suppose the relief valve is stuck in closed and doesnāt open during this short phase. Then OP drops and the gasket does its job.
If the relief valve is supposed to open at some 60 lbs at the base of the filter, what happens with that pressure inside the filter canister? If the same pressure is works against the outside seal I could imagine that this thin rubber seal might be overwhelmed by some 80+ lbs - thatās the pressure I keep in the tires of my racing bike. The oil change will tell - hopefully - what gave ā¦
Good to hear though that the relief valve lends itself to cleaning and fixing:-)
Jochen,
I am a big believer in the Occamās Razor theory, paraphrased as āthe simplest solution is probably the right oneā.
Remove the oil pan drain plug, drain the oil, remove your oil filter canister, remove the old seal between the filter head and the canister (making sure there arenāt two there), install a new seal, install a new filter, tighten the filter canister to spec, install the drain plug, add oil, and start up the car. Iād say there is a very good probability that will fix your canister oil leak. It did when I had similar leaks in my 1969 E-Type before I installed an aftermarket spin on oil filter adapter.
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A clogged filter will increase pressure at the relief valve, Jochen - and will reduce gauge readingsā¦
Changing filter will usually increase oil pressure readings - but oil viscosity always plays a part in oil pressure readings. Nominally, gauge reading should not exceed relief pressure - but a housing leak would reduce readingsā¦
Sure Paul, Occamās razor advises well to start with the easiest assumption - and Iām willing to follow.
Iām not so confident though whether the easiest assumption really meets the facts - that this gasket in this canister with this engine oil has lasted well for over two years and maybe 2000 mls.
But, as you say, letās start with an easy test ā¦
I concur with the easy test. May or may not fix but will not harm.
Not so confident that the thin oil ring seal will fail at start up and leak, yet resume sealing on warm up. Seems that once āblownā by xās pressure, it will remain so. Leak continues. But, OTH, it is not a full on blown seal merely a seep. So, that just might matter.
Not quite on point but similar. A You tube piece.
UK guy, iron thumper. Messing with a pressure regulator for the power steering of his repowered Russian, ZIL, X Soviet army vehicle. Cranked in a lot of PSI, Operated the PS. Blew out the end seal n the steering box. A semi flat plate with an āoā ring. Blew oil all out the front. Removed plate and āOā ring splitā¦
But, it may well have been there for decades and as such hardened. A seal for a ZIL at the local parts place, No such luck. Replaced with one that was almost the same. It worked. with reduced PSI, this time!!! ā¦
The week before we did an oil and filter change. The rubber seal in the oil filter canister seemed a bit hard, but it wasnāt torn or otherwise damaged.
We also found the bolt fixing the cam feed pipe a bit loose - you were right, David - and tightened it down. A new filter and seal came in. As the car was sitting for almost 10 days now I was quite curious to see how it would behave: the ground underneath was clean and no more oil was pressed out upon startup at the oil filter canister. Iām very happy that - at least it looks that way - the oil leak issue has been solved with easy fixes.