On the way to the Pittsburgh car show I thought I blew an oil seal with the billowing white smoke and all, then the trans started slipping a lot. Had to pull over on the turn pike and get some trans fluid and limped to a hotel, stopping and adding more fluid several times. Rather than deal with a local Jag shop at their prices, came back home on a flat bed. Up on my lift there is a substantial leak coming from the dip tube area (passenger side) somewhere ?? Not leaking from the trans pan anywhere. Not certain where to start from. Will buy the Haynes manual on the TH400 as mentioned in the "book" I call the Palm manual !! Really can't see up very much... looking for ideas on where, how to start !!
Thanks,
Ken in WV

 

Gotta be the transmission cooler lines. Hopefully it just came loose.

Edit: here's a pic where the two cooler line fittings are:


Padre

 

yep ditto on those lines the top one is a little hard to get a wrench on with the dip stick tube there but it can be done also use line wrenches

 

Was the smoke coming from exhaust? If so check the rubber line going to the vacuum modulator. If it has tranny fluid in it then change the the vacuum modulator.
Maybe change the oring on dip stick tube while your there.

 

Thanks to you three.. Just getting ready to check things out.... I let the cat rest for a few days before surgery !!!! Looks like the cooler lines will be difficult to access ??
Ken

 

My front seal leaks on my trans and it goes everywhere, maybe best to wipe things down and go for a run to help spot the origins of the leak.

My front seal doesn't get on my exhaust enough to smoke though, so maybe the lines like someone suggested.

 

the trans comes out pretty straight forward thing to do why not just put in a new seal

 

Because his seemed to be a rapid emptying of the fluid and was around the dipstick tube, I lean towards it being the cooler lines.

If it's difficult to see the lines, buy one of these, $20, use with a tablet: https://www.amazon.com/gp/product/B01B5KQ8DQ

Padre

 

Easy to access the transmission area when the passenger side muffler and pipes are off. Cleaned the area up a bit and noticed that the rubber connector between the tube and the vacuum modulator is "burned" but really does not look or test out to be compromised ?? Will still replace the connector. The cooler tubes seem to be connected correctly and tight. So next will add some trans fluid and see where it leaks from ?? see a "hole" above the two cooler lines, is some tube supposed to go in there ??? Really looked clean....

 

well that is toast good luck in your search

 

Bought a vacuum modulator for GM TH400 transmission on ebay for $14 includes the rubber elbow and free shipping verses $188 for the exact Jaguar part number.... Wow, big difference.... Question, if the line to the modulator and the modulator have tranny fluid inside, anything special to do before replacing ?? What would keep it from filling again ??
Thanks,
Ken in WV

 

The diaphragm in your old modulator has broken, and ATF gets sucked up the vac tube (if the line is intact) or blown out all over the place if the elbow is shot, like your was. replacing the modulator and the elbow should fix it. BUT ensure that the vac tube from the elbow to the A bank vac spigot is clear and vac-tight. Replacing it with a 4mm silicone vac tube is a very good plan. Also, ensure the new elbow is nowhere near the exhaust or it will burn through again and the same thing will happen. When I did mine, I managed to find a brass 4mm barbed connector and used that instead of the OEM plastic connector from the elbow to the vac tube.
Greg

 

Greg,
How did you get to where the blue tube connects above the cooler lines, take them off ??
Ken

 

On my car you can get to it from underneath, you might have to move the exhaust, might not, on mine it is OK. If you decide to change the vac tube, tie a bit of string to the old tube and pull it upwards into the engine bay. Then the string can be used to pull though the new tube.
Greg

 

Gregg,

"BUT ensure that the vac tube from the elbow to the A bank vac spigot is clear and vac-tight. Replacing it with a 4mm silicone vac tube is a very good plan."

I am unable to see the vac line from the top and while I may be able to remove it, how the heck did you connect it back ?? Is there a difference in the LHD that I have ??
Thanks,
Ken

 

The vac line should be connected to one of the spigots in the cabin end of the A bank (US passenger side) inlet manifold. look carefully and you will find it. It might be joined to a Y piece first. My idea is that you tie string to the bottom (gearbox end) and pull the existing tube up. Reverse to replace.
Greg

 

The vac line should be connected to one of the spigots in the cabin end of the A bank (US passenger side) inlet manifold. look carefully and you will find it. It might be joined to a Y piece first.

OK, I thought it was on the bottom, but I now see the Vac line going through a holder and up into the engine area, but I do not see where it connects ??

I will look some more, but need some further guidance... Guess I'm becoming dummer at 74 lol But at least, I'm still on the green side and enjoying playing with my kitty kats....

ken

 

Some photos to help. The plan view of the engine shows the brake fluid reservoir near the end of the manifold and the tranny dipstick. In the next photo you can JUST dimly see the blue vac pipe rising up, and the third shows an engine out of the car and the vac pipe takeoff on the manifold end.
Basically you have to carefully move loom and stuff out of the way and you will see the vac pipes (of which there are several) on the end of the manifold.
Greg

 

yes that tube follows the dip stick tube up and goes through a rubber grommet flange that bolts to almost the top of transmission bell housing which will make it hard to pull back through. It will connect to the lower vac fitting on rear of the right manifold which is the larger one on that block mine has no tee in it but I guess there could be one. As your is a right side driver that may compound the problem but the biggest hurdle I see will be that rubber grommet that by the way will be baked hard and very brittle. Hope I could help

 

Thanks again to you both.

I "believe" the tube with the white line is the vac tube coming through the large rubber hose protector, goes through a "filter" and then into the "Y" connector.

Rather than replace the tube if it is intact, it would seem that I could "blow it out" and remove any trans fluid and then reconnect ??? Should I do the same to the filter ??