The Jaguar Gods may be shining on me

Greetings mates …

Lately I’ve developed an annoying oil leak. A quick peek looked like it was possibly coming from the area between the engine and transmission. Immediately fearing the worst I though … “rear main crankshaft seal”, not the end of the world but definitely a transmission pull … groan !
A thorough cleaning and close inspection of the area tells me that it definitely seems to be coming from the oil filler tube housing…YEA !

Number 9 is listed as a baffle plate (EAC 4886) is this a gasket or is it actually a plate? If it’s a plate how is it sealed?

Number 6 is listed as a bushing (EAC 2632)

Checked online with the usual suspects and I can’t source either part. Any help !!

Dennis,

As far as I can remember item 9 (EAC4886) is a ‘baffle plate’ to prevent unnecessary ‘splash back’ and a spare is apparently still available from JDHT according to their web site. However, I would be very surprised if the leak is from that point because there is very little pressure on that filler pipe providing the engine breather system is working properly (unlike pumped engine oil pressure for example). I think items 9 and 7 are sealed with ‘gasket goo’ in the absence of a gasket.

The filler tube is merely a ‘push fit’ through item 6 in to item 7 and as you say, EAC2632 appears to be ‘NLA’ from Jaguar.

I would have thought that a more likely source of your oil leak in that area is from one of the engine breather rubber tubes or their connections.

Item #9 is a metal baffle which is nothing but a metal plate. I’m fairly certain there was no gasket on either side from what I can remember. I believe I assembled mine using black RTV and have not had issues.

If you really wanted to, you could buy a roll of gasket material and, using the baffle as a template, make a gasket, but it all honesty that is probably overkill.

Number 6 is simply a rubber ring which locates the tube and prevents it from leaking.

Are there types of oil leaks that are not annoying?

ARRRGH …

After giving the bottom of my engine and transmission an industrial strength cleaning (it almost looks brand new under there) I can finally see where my oil leak is coming from. Well I can almost see !

Bryan is correct, it’s not coming from the oil filler housing (My God man, don’t you get tired of being right all the time) :blush:

The oil weep is coming from the rear area of the engine where it connects to the transmission. But I don’t believe it’s from the rear crank seal. The area under the flywheel in the bell housing is dry. It appears to be coming from the area around the rear of the oil pan that I can’t see because of the transmission bell housing. But it’s definitely not leaking down from above that.

I’m now inclined to believe that It’s coming from the rear of the oil pan and dripping down to where the two while arrows indicate. This may make some sense since I had my transmission rebuilt a few months ago and removing and replacing it may have jarred the oil pan ??

QUESTION … The torque on the oil pan bolts is a max of 20 lbs. Can I just tighten them up a bit more or would I be causing more problems by doing that? Happily I’ve never had to deal with the oil pan gasket so I know nothing of the nature of that beast.

The Jaguar Gods givith and taketh away !!!

Dennis,

I know, annoying isn’t it? :slight_smile:
OK then, I’ll give you another couple of chances to prove me wrong with the following anecdotes.

I’ve only had two instances on my XJ40 of engine oil leaks. The first one was easy to see and easier to explain. The leak was from the oil drain plug after my botched attempts to fit a Helicoil insert in the sump plug thread after it stripped the first time I tried to remove that plug. The previous oil change by an ape at a main dealership had resulted in the plug being over-tightened so that the extremely brittle age-hardened sump threads had cracked and caused the plug to seize in the hole. Having been forced to use brute force to unscrew the plug, that effectively stripped all of the threads out of the sump. My attempt at re-tapping the hole to fit the Helicoil insert was not a complete success in that the newly threaded hole was not ‘square’ to the sealing face of the sump so the normal sealing washer was not 100% resulting in a steady drip of oil. JB weld fixed the plug in permanently and thereafter I used a vacuum pump to drain the oil every time it needed changing.

The other leak was less obvious. When I replaced the cylinder head after a gasket change, in re-fitting the cam cover I had not taken the precaution of ensuring that the blind threaded holes in the head for the cam cover screws were completely clear and dry and free of oil I had used to lubricate the camshaft bearings etc during their installation. As a result, despite supposedly torquing the cam cover screws down evenly to the required level, some of those screws were ‘hydraulicing’ in the blind holes so they were not properly torqued at all and over time loosened up.

Guess what? As a result the cam cover leaked a tiny amount of oil past its soft rubber gasket and guess where that oil ended up?

Because the AJ6 engine in an XJ40 is inclined downwards towards the back, that slight seepage of oil ran down the edge of the cylinder head to the rear and from there it eventually dripped on to the bell housing/engine joint and appeared exactly where your arrows show your leak to assemble.

Could your car have the same problem?

If not, you’ve still had a good read! :wink:

Bryan …

As far as a stripped oil pan drain bolt… been there, done that.

I had the same exact scenario you mentioned. I believe my oil changing “specialist” must have muttered the words “If tight is good well gull durn’it super duper tight must be gooder” before he released a meteoric glob of redman chew out of the corner of his mouth. That was years ago and fortunately I had more success with the Helicoil repair and it hasn’t been an issue.

While it’s difficult to be 100% sure because of the tight quarters I don’t see any oil coming from the rear of the cylinder head or above it at the rear of the cam cover.

Because the oil is pooling at the two points in the picture I don’t believe it would be coming from the rear oil seal, I can’t see how it would form that migration path. As I mentioned there is no oil pooling under the flywheel. If you look closely at the bottom of picture there is actually a hole machined into the area where the transmission bell housing is bolted together. Any oil leaking from the rear oil seal should be dripping out of that hole.

Which leaves me back to the rear of the oil pan gasket.

Fortunately it only amounts to a couple of drops overnight so I guess I’ll just live with it.

Any advice on the wisdom of retorquing the oil pan bolts ? I read an article that called for removing one bolt at a time, cleaning it, and then retorquing it. But when it comes to car tips … I’ve been lied to before

Dennis,

There isn’t a gasket on the oil pan - the mating surfaces are coated with ‘Hylosil 102’ (whatever that is!) so ‘re-torquing’ the sump bolts will probably have no beneficial effect.

Bearing in mind the complexities of removing the oil pan to clean it up and re-seal it, I would live with a small leak!

Hi Groove,
The metal washers under the cam cover screws on my car became very brittle. most of them were in several pieces and I could snap the unbroken ones easily like biscuits between my fingers.They were made of metal and I have arthritic fingers too !
I’d already bought the new rubber seal
but I ended up just replacing the washers and it’s been oil tight for 12 months now.

I’m thinking if the washers on the sump bolts are made from the same material maybe a few of yours have cracked or broken and the bolts are not as tight as they should be.

I’ve had two other oil leaks in the past, one came from the tensioner cover near the distributor, and the other from worn O rings on the oil by pass housing underneath the filter, but on both occasions, I first noticed the drip in exactly the same place as your white arrows show. There were no real ’ tell tale ’ trails of oil I could convincingly follow from either leak to that area and as the leaks were so minor it took me quite a while to find and eliminate them.

I was left thinking maybe the airflow over the engine when driving propels any oil leak rearwards, possibly along the top of the ledge where the sump meets the block. That ledge ends directly over the area where the drips accumulate.

Does the leak only appear after a drive or would it still drip from the same place after cleaning it and then leaving the car stood overnight say ?

cheers

Speaking from my own experience, I think the washers used for the cam cover bolts are made from a different alloy than all the other washers used on the engine. I believe I had to replace almost all of my cam cover washers due to breakage and cracking, but didn’t have the issue with a single washer on any other area of my engine.

Is it possible for you to clean up the bottom of the engine so its completely clean and dry, and then get under the vehicle while its running? Safely of course! With a light, you should be able to see where the oil is streaming from.

A second option is you could buy a leak detection tool like the shops use. Basically, you just add a dye to the oil and then use a special light and glasses to be able to see the dye/oil seepage.

More input …

My car has been sitting at home for 5 days (went on a great ski trip, only fell once!). Not a drop of oil underneath when I returned !

If my deductive powers are correct I can now eliminate the oil pan gasket as the source of my oil leak…right?
The leak occurs when I drive the car and since the oil pan is not under pressure (actually I believe it’s under slight suction with the motor running) If it doesn’t leak sitting around then it shouldn’t leak with the engine running.

This brings me right back to the crankshaft rear oil seal which most definitely would be affected by the engine running.

The devil of it is, is that the leak is right where the rear part of the oil pan is hidden by the transmission housing so I can’t see that area.

What say youse guys ?

At rest, I suspect the oil level in the sump is below the gasket.
When the engine is running and pumping the oil “upstairs” and slinging it around
as it comes off of the crankshaft, that will test the pan gasket.

Sorry for the negative feedback,
-Ken

At this point, I would suggest purchasing a leak detection kit in order to give yourself some confirmation on where exactly the leak is coming from. Kits can be purchased starting for about $60 USD and go up from there depending on how extravagant it is. Considering both seals would be a major pain to replace, I would certainly want confirmation before rolling the dice on one or the other.

Too bad you’re not local. We could get your car up in the air and figure this out. Good luck!

Thanks guys …

Ken I agree with you, and I was kinda thinking that even if the oil pan isn’t pressurized it would still be subjected to dynamics associated with splashing and possibly heat issues after running for a while.

Brett, I like the idea of the dye test but as I mentioned the source of the leak seems to be hidden behind the transmission bell housing adapter where I can’t really see the exact source.

I guess if I decide that I absolutely can’t live with the small oil “weep” my next step will be to pull the transmission and have a look see !