Transmission failure 3.2 litre Sovereign

[db40]

Yikes - I have a problem with the transmission!

The car is a 3.2 litre Sovereign, an early battery in boot car.

I don't use the car very often, so it had become a little dusty. I decided to wash it and since the driveway has a slope, I turned on the ignition but did not start the engine and let the car roll out of the garage. I did this so that I would only have to fire up the engine once and also so that if the brakes are binding (thankfully they seem OK) it would be noticeable in a reluctance to roll out of the garage.

Once out of the garage I saw a small but noticeable patch of ATF on the garage floor. It does not normally leak ATF, so this concerned me immediately.

I checked the ATF level to see if it was lower (I had not started the engine or followed the checking procedure, so this was more of an indication than a proper measurement).

To my surprise it registered very high indeed - a good 2 centimetres over the white plastic part on the dipstick. I have not put any ATF in since I changed it at least 2 years ago. When I have looked at the dipstick in the past with the car having sat for a period and without starting the engine, the level has not risen like this - it has stayed at a constant level lower on the dipstick's white part. The ATF itself does not look burned:

P1130242 by *D*B*, on Flickr

It have heard that a failure in the radiator can cause coolant to enter the transmission, so the first thing I checked after the transmission oil was the coolant level. This was correct, so presumably the problem is not this. I imagine that the increased volume of fluid in the sump to show such a big rise on the dip stick would leave the header tank empty - or at least notably reduced.

At this point and with a heavy heart, I started the car. The engine caught with a wobble felt through the whole car and it ran rough and (IIRC) slower than normal. The transmission made a frothing sound. I briefly tried to see if I could put the car back in the garage (it has died in the part of the drive which will make the car difficult to recover with a tow truck) - it moved forward very reluctantly and with a great deal of slip. I only tried this for a couple of seconds and shut the engine down since I know nothing about transmissions and don't want to cause any more damage which I could have avoided!

What could have caused this? Does it sound like the torque converter has failed in some way? - Could the ATF in the torque converter have drained into the sump pan for some reason? - It normally sits there no matter how long the car is parked up and doesn't drain into the sump doesn't it? Would a failed torque converter cause fluid to flow into the transmission sump?

I have had it suggested to me that the transmission pump could have fired the fluid into the 'box and now there is no pressure to the clutches. This sounds plausible to me because it seems to fit the symptoms, but I know next to nothing about automatic transmissions.

This problem has come on very suddenly. The last time I drove the car was several weeks ago, but the car ran perfectly with no strange behaviour.

It is not entirely without symptoms though which in retrospect could be transmission related.
The car will occasionally produce a strange and slight vibration (like the engine is not quite happy rather than a rough road surface) as speed increases. This is highly intermittent. I actually ruled it out from being transmission related since the vibration does not stop if the transmission is put in neutral. In retrospect, I may have been wrong to think this! The transmission also occasionally thumps into drive and reverse more than it should, but the car's engine idles slightly high. The idle speed was turned up slightly (presumably at the ECU) by a Jaguar main dealer in the mid 1990s to cure a stalling problem as the car came to a halt at junctions. My late father owned the car back then.

The car is not in a position on the drive which will make recovering it with a tow truck easy. Do I risk causing further damage to the transmission if I move the car forwards (up the hill on the drive) to a better place?

I don't fancy my chances of pushing a car of this weight up the hill! Still, I will have a good go if running the car could further damage the transmission!

Thanks for you time,

David


P1130239 by *D*B*, on Flickr

[poprivet]

Where is the source of the leak? There is a breather at the very back, if it is from here it wouldn't concern me if the unit has been standing for a while.

Run the engine and once the valve block repressurises I would expect it to operate as normal. The owners manual shows the correct procedure for level checking with the engine running either hot or cold.

(Obviously if there is a leak elsewhere, that needs repairing first).

The high idle can be put right easily, they do suffer from throttle block gumming up, and there is a procedure for correctly setting the idle control valve, if it was last looked at in the mid 90s, then it is in need of attention after well over 20 years.

[ptjs1]

David,

I understand your concerns but there may be nothing much wrong at all. A car standing for a while and then being rolled on a slope can give very misleading fluid levels. If you look at the angle by which the dipstick enters the box, yo'll see what i mean. And if the fluid flows back into the sump (which it will to some extent if it's just sitting there) then you can quite likely get a rough running until all the fluid has moved back via the pump to the valves, torque converter etc.

Just a suggestion, but I'd be tempted to leave the car running for a while, then cycle the box through all positions at rest before condemning anything just yet.

Good luck

Paul

[db40]

Where is the source of the leak? There is a breather at the very back, if it is from here it wouldn't concern me if the unit has been standing for a while.

Run the engine and once the valve block repressurises I would expect it to operate as normal. The owners manual shows the correct procedure for level checking with the engine running either hot or cold.

(Obviously if there is a leak elsewhere, that needs repairing first).

The high idle can be put right easily, they do suffer from throttle block gumming up, and there is a procedure for correctly setting the idle control valve, if it was last looked at in the mid 90s, then it is in need of attention after well over 20 years.

The leak appears to be from the sump gasket to me - it is from the front end of the transmission anyway. It isn't a big leak, though clearly any leak needs fixing! it could be the gasket isn't as good as it could be and the higher fluid level has exposed this.

Do you think it is probably on balance safe for me to start the car up and see what happens? I am a bit nervous about doing (further?) damage to it

[db40]

David,

I understand your concerns but there may be nothing much wrong at all. A car standing for a while and then being rolled on a slope can give very misleading fluid levels. If you look at the angle by which the dipstick enters the box, yo'll see what i mean. And if the fluid flows back into the sump (which it will to some extent if it's just sitting there) then you can quite likely get a rough running until all the fluid has moved back via the pump to the valves, torque converter etc.

Just a suggestion, but I'd be tempted to leave the car running for a while, then cycle the box through all positions at rest before condemning anything just yet.

Good luck

Paul

Here's hoping!

[poprivet]

Bear in mind that if it was coming from the breather it would likely run down and around the sump gasket and could drip anywhere, that is why I suggested you investigated it further. You can't go by the dipstick at this point as Paul and myself have already said.

[Brakebuster]

the points to check are

the gasket of the sump,

the vacuum valve on the right side,

the flow and return oil cooler union at the front right position ,

the vent pipe, though this is 3/4 the way up the right side by the bell housing, and a pipe runs to the back where the output shaft is

the only other place is the seal to the pump face from the torque converter , this would ( as said ) run down and come out of the bottom of the bell housing plate

BB

[db40]

Thanks for the tremendous help I have been given with this problem.

I will have another look at it to see where it is leaking from.

David

[ptjs1]

..also the joint of the dipstick tube to the sump. Since changing my fluid and filter, I have a very small weep from this area and it gets a little worse if the car has been sitting and the fluid draining back to the sump.

PAul

[Brakebuster]

..also the joint of the dipstick tube to the sump. Since changing my fluid and filter, I have a very small weep from this area and it gets a little worse if the car has been sitting and the fluid draining back to the sump.

PAul

good point

BB

[db40]

I have some spinal problems unfortunately and struggle a bit with ground level activities - so unfortunately my investigations are not as successful as they should be

As far as I can see the leak is on the left hand (passenger's UK car) side of the transmission. That is certainly where the ATF staining/wetness is. There doesn't seem to be anything very much on the right hand side.

The rear of the transmission shows some evidence of moisture/wetness, but it is nothing like so apparent as it is the front of the transmission. It might be though that evidence of fresh ATF wetness is disguised by the overall dirtiness of this area - contrasting with the relatively clean front of the transmission. I am pretty sure it isn't coming from the sump gasket now though, you are right in that it is settling at the lowest point and flowing with gravity. Here are a couple of photo I took - one of the rear end of the transmission, one of the front:

P1130256 by *D*B*, on Flickr

P1130260 by *D*B*, on Flickr

[ptjs1]

David,

The photos are interesting as I think it's coming from quite high up. Although oil can "move around" when it leaks, it's tendency is naturally to fall to lowest point. However, the shape of the stain high up at the rear and the apparent increased wetness at the front makes think that it IS NOT:

- the sump plug (far too low)
- the sump flange (too low)
- the cooler return pipe (dry)
- the selector lever (too much above at front and at rear)
- the connection of the dipstick tube (although damp, it wouldn't go up from here, it would drip straight down)
- the rear output flange (much too much at front and up high)

So, although that doesn't help you much, I think you can eliminate some areas! Any chance you can spray a load of degreaser and pressure wash it off?

Cheers

Paul

[db40]

It does seem to be coming from high up and probably near the front, doesn't it.

[db40]

I wanted to make absolutely sure (or as certain as I could be without removing the sump) that there was no coolant crossing over into the transmission from the radiator, so I removed 2 litres of ATF this afternoon with a Pela 6000 suction pump. I reasoned that if coolant was getting in to the transmission then it would most likely mix with the atf resulting in an oleaginous mess, or separate with the atf floating on the coolant. Either way, since the dipstick enters the pan low down, then I would see evidence of coolant if there was any - or perhaps burned fluid. Either way, the atf I removed looked to be in good condition with no burning and no evidence of coolant.

So I decided to start the car. And it started ...normally! There was perhaps a little more vibration than normal for a second, but nothing striking and the car settled to a normal and smooth idle. Drive and Reverse engaged normally - there was nothing to suggest that there had been a problem of any kind.

So it is either a self-fixing Jaguar or a neurotic owner - you decide! I will have the transmission checked out though, to determine the cause of the leak (which appears to have stopped) and to discover if the loss of drive was a one-off due to a draining torque converter not having refilled, or whether it is a harbinger of problems to come.

Thanks to everyone who has helped me on this - I do appreciate it!

David.

[PeterDavisX300]

Always a sigh of relief to find that things are well. Older cars can be fickle right-enough, perhaps a trait that some of us enjoy. Even better when we are all kept informed of results after the fact. A good educating thread.