Problem dismantling J Type overdrive

[tonydgray]

Hi all

I'm in the middle of a j type overdrive conversion and I need to split the overdrive to renew a couple of gaskets to sort out an oil leak. Although the bolts are undone the case and gearbox only part company between 5 and 10mm. I've found this and it sounds like the problem I'm having:

"The manuals tell you that before removing the gearbox you should drive the vehicle and engage OD and then disengage with the clutch depressed. This will release the spline loading between the planet carrier and unidirectional clutch, which can make removal difficult. What this means is that the unidirectional clutch and the sliding clutch can be positioned in a way that there is large rotational forces in opposite directions on the splines of the rear of the mainshaft. The forces can be so great that the mainshaft can't be slid out of the OD unit. Once you have it on the bench, you aren't going to put it back in the car and run it in OD, no way. Apparently this doesn't happen in the A Type, or if it does, the forces are less. I've never encounter this problem but I know others who have had the problem; it is real. The spline loading can be relieved by moving the sliding clutch away from the annulus (the direct drive position). The manuals suggest the following procedure if the mainshaft is hung up: operate the solenoid, remove the plug in front of the solenoid and force oil into the chamber around the operating valve at the front of the solenoid. (The adaptor hose normally used to connect a pressure gauge can be used to connect to a grease gun filled with oil.) This should shift the unit out of direct drive thus relieving the spline loading."

I'm thinking now that I need to get hold of the bits to pressurise the system in order to get the thing apart. Has anyone got and ideas that could help here.

Thanks

Tony

[WPR678B]

Hi Tony,
I have only worked on the D-type that i have but i found that it must be split as arrowed in the attached picture to seperate it from the gearbox. I also tried to split it complete with the adaptor, but as you have found, it wouldn't come off!!
Hope this helps?

[tonydgray]

Thanks for that I shall be having another go today so crossing my fingers, thanks for your help. Cheers Tony

Originally Posted by WPR678B

Hi Tony,
I have only worked on the D-type that i have but i found that it must be split as arrowed in the attached picture to seperate it from the gearbox. I also tried to split it complete with the adaptor, but as you have found, it wouldn't come off!!
Hope this helps?

[tonydgray]

A quick update. The information I quoted in the first post of this thread was spot on regarding some residual loading on the internals making it very difficult to split the overdrive cases apart. This initial information was taken from:

http://www.buckeyetriumphs.org/techn.../JOD2/JOD2.htm

I did not have anything to hand to test this by pressurising the system but luckily I stumbled across a page that outlined converting a grease gun for this purpose, it can be found here:

http://www.metalwebnews.com/howto/oi...unconvert.html

I picked up a pretty cheap grease gun and carried out the necessary modification. I also made an adapter to join the grease gun hose to the plug in the overdrive housing. I then operated the solenoid, pumped in some oil an low and behold I heard something move in the overdrive. I stopped pumping and tried again separate the cases and they fell apart without any problem at all.

I hope this post is helpful someone else with the same problem.

Cheers

Tony