So I headed out in the car today, and wasn't gone more than five minutes before smoke started coming out of the bonnet. Not a good sign normally. "Marelli fire" was the first thing that came to mind, but there was no loss of power, so I headed home (risky, I know, but there wasn't that much smoke) and opened the bonnet to find liberal amounts of dark pink oil splattered around the engine in about a one foot radius from the oil-covered tranny dipstick.

Now, I did pull it out to check the level this morning, but there's only one way to put these things in, right? I'm not sure how that could have happened - I called the dealer I bought it from, as he'd replaced the torque converter, and he said he was quite mystified. The mechanic who did the work is away, apparently, but another mechanic there was also mystified. I reinserted it and ran the engine, blipping it to get the revs up, but it didn't happen again.

Is it possible to put the tranny dipstick in the wrong way? Backwards or something? There's nothing to hold it in position other than gravity, really. That, and the coiled stick itself. Even if I could have somehow put it not all the way, or it sprung out or something, the oil shouldn't normally gush out like that, right? It was fine yesterday, after driving a total of about 100 km.
Oh well. I have called a local specialist garage in European imports to have a look at the car for its overheating issue, so will mention this to them as well.

And I got to have fun cleaning up the spilt tranny oil as best as I could. I think I got most of it. Now the car has shown a total of four mechanical problems in two days of ownership....

 

When replacing the tranny dipstick you have to firmly push the dipstick home. I expect you may not have fully done that? No reason to despair about a few problems, you have bought a 24 year old supercar that has a few simple to fix items that previous owners have neglected. What else can be expected? Just fix things as they come up and after a bit you will have a fully reliable car.
The real decision for you is to answer the question "Is this the car for me and am I going to keep it?". If the answer is Yes, get stuck into the fixes. If No, sell it.
Greg

 

There are 2 o/rings on the top of the dipstick, on the section below the tab you grab hold of to pull it out.

Item #2 in the attached drawing.

Attachment 133321

Also there is abreathe hose running along teh TOP of the transmission, it may be blocked or kinked, since the trans has been out recently. Item #14 in the attached drawing.

 

Hi Grant. Thanks for your reply - the first attachment didn't attach it seems. If you could post it again, I can compare with mine. I don't think I noticed any rubber O rings. There are plastic ones the same colour as the handle - here's a pic. Are there missing O rings here?

Dipstick partially removed.




Dipstick fully inserted.


I don't think there's any way to check the breather tube without actually removing the transmission again, but I'll mention it to the dealer as a possibility.

Greg - Thanks. I'm not actually despairing as yet - I've been lurking on this forum for a year or more, so I knew I'd have to throw either a lot of money or a lot of time (or both) at it. I just thought I already had - the shop spent a couple of months on working through some problems, and I had hoped they'd fixed the heating one at least, so it was disappointing to realise it was still an issue. Anyway, it's the car I've wanted since I was first interested in cars, one I've lusted after for thirty years, so I'm going to hang onto it for a bit more, I think....

And thanks for all the help and advice people have given on this forum - it really is very much appreciated.

 

Good for you. And what a dream car they are. The dipstick top, OEM, had a rubber grommet thingy round the topmost part, above the second circular divider. Mine has never had it, and when I fitted one it tended to make the dipstick stick in the tube, so I removed it. I doubt you will have the trouble again, but if you do, it is a blocked breather as Grant indicated.
In the attached rather poor shot, the breather tube is the one that runs more or less horizontally from right to left, starting with the pale tube emerging from the box towards the top of the bell part. Your garage might be able to get to the end of it and see if they can check it.
The engine bay looks lovely and clean, lucky you!
Greg

 

Maybe this time.

Greg is correct, mine had the Red dipstick without o/rings. I was, and still am, too stingy to get Jag o/rings, really. So genearic from my supplies worked, and yes, the stick is harder to extract, so I also ditched them. Mine had a kinked breather tube, my bad when I refitted the engine etc and did not pay attention, or drink enough, probably the latter.

 

Greg - Thanks for the pic. That gives me a very good idea of what it is. I think I might let the shop guy know what you have come up with here. He says that they actually cleaned up the engine bay before delivery - it's not shiny and polished, but it's not a rat's nest either. It's a relief to hear it's not likely to happen again - having smoke come out of your bonnet is really not the most welcome sight in the world, especially after you've read all the Marelli horror stories....

Grant - Ah, those kinks in the tube will be where the dipstick meets resistance on the way down. I suspected something like that from the very flexible stick. Thanks for reposting the diagram. Very helpful. And that's two votes for no O rings, so I'll leave mine as it is for now. If it happens again I might add one, just to block any spurting out.

 

Had 5 V12 auto Jags, none had O rings on the dipsticks.
So that's seven votes!

 

The No-O's have it, then!

 

Well, I risked taking it to the European imports garage, as it was only a ten minute drive away, and while I thought I saw some wisps of smoke on the way, I definitely saw some pulling into their forecourt. The dipstick had been pushed up half an inch and there was oil spattered around - not nearly as much as last time, mind.
The garage guy is going to take a look at it, but his hypothesis at the moment is that coolant is getting into the tranny oil. When the torque converter was changed, the oil was clearly adulterated, but it seems that the dealer only changed the converter and didn't bother tracking down any leak.
Well, this will no doubt cost me, but once that's sorted, there's only the next dozen or so niggles to sort out.... (Anything that doesn't affect how it drives can wait, however.)

 

The breather has NOTHING to do with dipstick tube.

It is a small, about 6mm ID hose that is attached to the body on the RH side of the trans tunnel.

Coolant in the trans fluid??, that can only come from the trans cooler in the RH radiator tank, AND, you will certainly have trans fluid IN the coolant, and that is a HUGE mess to clean up.

IF you have coolant in the trans fluid, AND/OR trans fluid in the coolant, DO NOT drive that car, DO NOT even run that engine until it is sorted 100%. Irrepairable damage to the transmission and engine WILL cost you stupid money to fix, even if you are a competent DIY person. If you rely on workshops, OH boy, that will be huge.

 

Further to Grants most vital post, the tranny oil goes through a coil set inside the radiator RH side tank. In this diagram it is the two smaller outlets below the top water inlet are the inflow and return:


The two pipes numbered 9 and 10, and their end fittings numbered 14 and 15, pipe the ATF from the tranny to the radiator and back. They run along the RH side of the engine from the RH side of the tranny.

This tranny oil cooling coil within the radiator side tank is meant to be completely separate from the coolant, which surrounds the coil and thus cools the tranny fluid. If this coil is rusted out or perforated, then the coolant gets into the transmission fluid, and vice versa, and the coolant pressure pressurises the tranny internally, thus blowing out the dipstick. The only solution is a new radiator.
The gearbxx breather may be blocked, but it would not pressurise the tranny in a short few minutes drive to that extent.
Greg

 

Ouch. I don't know for certain if it's coolant in there now. I do know that there was earlier, and that was supposed to have all been cleaned up and all fluids replaced (the tranny oil that came out was at least clear).

This is the tranny oil as it was before the transmission was fixed. It doesn't look like this now, thankfully. Could that have been because the oil was just too new to have gone like this?

The torque converter was replaced before delivery, when this photo was taken. While I assumed it was properly fixed, I am starting to doubt it now. I bought this car from a specialist dealer in SIII Daimlers and XJSs, and am starting to seriously wonder if I was duped.

How much is stupid money? Thousands of dollars is fine - well, up to around $5,000 and I won't mind too much so long as the car's sorted. More would have me fuming. And tens of thousands is not fine, and with the car undriveable, it won't even sell for much if anything. The only hope is that, with XJS prices increasing (especially the last year), I could spend say $10,000 getting it to sellable condition and not lose too much money. Perhaps....

Oh well. It's only money in the end. I can make more, and try and pretend this never happened....

 

Thanks Greg. If the issue is only a new radiator, I can handle that. I suspect, however, that it's a big IF. Oh well. It's in the shop now, because I unfortunately have neither the expertise nor the time to (learn to) replace a radiator. All I can do is wait for them to finish looking at it, and hope that they know what they're doing.

It's only done about 120 km max since I got it, so hopefully that wasn't enough to do permanent damage. At any rate, I am now expecting a bill of an amount that I would probably not want to tell my wife....

 

Grant's point about stupid money is that you must NOT drive it with coolant and ATF mixing. You will ruin the tranny (not big money to fix) and later on ruin the motor (very big money to fix). Given any luck at all the motor will be fine, so stop worrying.
The fact that there was water in the ATF and the original garage did not find the cause is typical of how lack of knowledge of the car lets down even well meaning garages.
So make QUITE SURE the people fixing your rad fix the tranny cooling coil in the RH side of it. If you want the best possible cooling fix, tell them to install a wizard cooling radiator. Made in the USA. https://wizardcooling.com/1976-1996-...inum-radiator/
Money really well spent.
Greg

 

The funny thing is, this place that supposedly fixed it is a specialist in these sorts of cars. I am not impressed.
I think I will amble down to the garage in the weekend and talk to them about tranny cooling coils, taking a printout of your very helpful post. Wizard's FAQ says nothing about international delivery, so I might email them.
Thanks again - it's just frustrating when you wait months for the car to be delivered because it's supposed to be getting fixed up, and it turns out it wasn't. Once I knew it was spouting oil, I only drove it a couple of minutes home, ran the engine for about five-ten minutes after replacing the stick to check if it happened again, and then ten minutes the next day, leisurely, to the garage, so I hope that's not too bad. Of course if I'd known that it was a really bad idea, I would've got the car trailered to the garage. Live and learn (thanks to this forum)....

 

You could consider installing an aftermarket transcooler and capping the old fittings on the radiator. That will contain the leakage problem and also give you a more efficient cooling system.

 

Thanks - not knowing what a "transcooler" was, I looked it up. It's something to consider if a new radiator doesn't work. The main question, I guess, is whether there's anywhere to put one under there....

 

I just can not see the justification that shop could come up with. Coolant in the transmission sump. Swap the converter. Zero on how the coolant got there!!!!


The cooler in the radiator tank placement has worked for years in most critters. but, and it's a big one, the coolant must be maintained.
Erst corrosion and the intermix.


A reverse check might diagnose that. Petroleum product in the coolant?


Amongst the solutions is as mentioned a separate air cooled matrix
for the transmission cooler. Placement? In front of the AC condensor.
Yes, three layers. Trans cooler, AC condenser and engine radiator.
Need a lot of air flowing....


Wowee, that's a ton of bucks.....


Carl

 

It's unbelievable, if that's really what happened. The only thing I can think of is that they wanted to keep repair costs to a minimum, perhaps afraid I'd want to get out of the deal.