Borg Warner Automatic advice needed

[Oily Puddles]

This question relates to a problem I am having on my 1965 Sunbeam Alpine Automatic fitted with a Borg warner 35 box. The gearbox was fully reconditioned about 4 years and 2,000 miles ago. I run Gulf Type F fluid in the box and it has been fine. I recently had to change the kick down cable. I got a new cable made and dropped the sump of the gearbox to fit it. While fitting the cable the hydraulic tube that feeds the rear hydraulic servo just dropped out of the gearbox onto the floor. There are 4 such pipes in this automatic gearbox and they only push in to their mounting holes and have no other securing mechanism. I pushed the rear servo pipe back in to it's mounting holes, fitted the cable, refilled the gearbox with new fluid and went out for a drive. Everything was fine at first then while we were out reverse gear just stopped working. We got home and I dropped the sump of the automatic box again and the tube to the rear servo was again adrift from one of its two mounting holes. I refitted everything, still no Reverse gear (or Park). I dropped the sump again this morning expecting to find the same pipe adrift once more but it is not. All pipes are secure and everything looks correct but I still have no Reverse or Park.
According to the Borg Warner manual both Park and Reverse use the rear servo so it seems reasonable that this is where the problem is. Can it get ‘air locked’ or have some other problem that I can cure at home with hand tools or does it require some kind of pressurised feed? The gearbox has a separate cooling radiator and fluid is pumping to the radiator and round the system. The car has Drive and Low gears working.

I am really stuck right now and am not sure how to proceed, any help or advice would be appreciated. We don't own a modern car and really need to get Alpi back on the road as soon as possible.

Oily Puddles

UPDATE. I made a mistake in my original post, it is not the pipe to the rear servo that 'fell out' but a pipe that I can't identify from the manual or exploded diagrams that is in front of the front servo release pipe. See photo. Is it this pipe that is causing my problems?

Edited by Oily Puddles on Sunday 12th October 14:32

[oakdale]

The sump holds the pipes in place so they cannot fall out once it's fitted.

I don't think there are any hydraulics involved with selecting park on these boxes.

If I remember correctly you have to push in a plunger on the side of the gear lever T handle to select reverse and park, is this working o/k?

Does the lever actually go into the position for park and reverse?

[Oily Puddles]

Oakdale,

After much more messing around under the car while it drips automatic transmission fluid all over me I can confirm that the Park function is purely mechanical and is working okay (it was an adjustment problem on the linkage I think). There is no button on the gearshift on a 1965 Sunbeam Alpine. The lever in the car sits in different lateral positions in the gate depending on which gear it is in but actually is just moving the lever forward or backwards at the gearbox end.
I have been told that the pipe that dropped out was a feed to the cooler. I still do not know why I have not been able to get reverse gear.

Oily Puddles

[oakdale]

I'm not sure but I think the kickdown adjustment could cause reverse gear not to drive until the engine is taken to high revs, try it with the cable disconnected at the carbs.

[wildoliver]

I can't particularly help I'm afraid but if it turns out spare gearboxes or parts would assist you I have a couple of these blooming things and some rebuild kits bunging up my workshop. On your problem I can't help but think it sounds a bit like either a seal that's dropped out when the pipe dropped and now the pipe isn't building pressure or an air lock

[Oily Puddles]

Having taken the sump off five (5) times now, ensured all pipes are tightly fitted inside, checked the kick down cable adjustment and taken just about all the skin off my knuckles working through the far too small inspections holes in the transmission tunnel I have gears and the hydraulics in the gearbox all seem to be working correctly.

Unfortunately I only have gears when I engage them using the lever coming directly out of the side of the gearbox. When I connect the mechanical linkage I either can't get the lever forward enough to engage Park or if I adjust it so that Park will operate I can't get it back far enough the other way to give me Lock. If I adjust it so that Lock works, I can't get Park. It must just be adjustment of the linkage length as none of these parts have been changed but it is very frustrating. There is just no room to work around the gearbox because it is such a tight squeeze when fitted in this little sports car. There is an adjuster in the linkage that works a bit like when you do tracking. You turn the centre piece and the linkage either gets longer or shorter as the two sections screw into or out of the thread. Unfortunately you can't reach the adjuster with spanners through the inspection holes or from underneath.

Old cars!

Oily

[oakdale]

The linkage shouldn't need adjusting after the job you've done.

I would think that either the linkage has somehow been damaged or the gearbox has moved relative to floorpan.

Did you have the box mounting off during this job?

[Oily Puddles]

I was having a bit of trouble getting Lock so while I was working on the gearbox i thought I'd adjust the linkage .......... Wish I hadn't now.

It is possible that the gearbox was moved relative to the floor recently (a couple of hundred miles ago) when the engine was taken out during the body restoration to spray the engine bay. The gearbox was left in the car but may have been moved during the process.

Oily

[oakdale]

If the front of the box wasn't properly supported when the engine was out, it would damage the linkage as the torque converter (which is left in the transmission) is quite heavy.

I'd disconnect the linkage and remove the gearbox mounting to drop the box down a bit to have a look.

[Oily Puddles]

All back together and working like a dream. I spent a lot of time getting the adjustment right on the mechanical linkage as well as with the kick down cable and it is working very well. One thing that I found was that over the 50 years of this car's life the gear shift lever had worn a groove about 3/16"deep where it rubs against the gate. This translates to quite significant lateral movement at the end of the lever. I sleeved the gear lever so that it slides tightly into each position on the gate and did the adjustments from an 'as new' position. Car now running very well indeed and changing gears smoothly. Thanks for all help and advice given.

Best Wishes,

Oily

[oakdale]

Oily Puddles said:

All back together and working like a dream. I spent a lot of time getting the adjustment right on the mechanical linkage as well as with the kick down cable and it is working very well. One thing that I found was that over the 50 years of this car's life the gear shift lever had worn a groove about 3/16"deep where it rubs against the gate. This translates to quite significant lateral movement at the end of the lever. I sleeved the gear lever so that it slides tightly into each position on the gate and did the adjustments from an 'as new' position. Car now running very well indeed and changing gears smoothly. Thanks for all help and advice given.

Best Wishes,

Oily

A nice looking car, they were a much underated car in their day.

I always prefered these to the MGB, is it a 1725cc?

[Oily Puddles]

This is my eldest son's Series IV. It is a 1592cc but it is fitted with 123 Ignition and a Weber 32/36 with an air induction system, so she goes nicely! My youngest son own a beautiful 1725cc Series V.

Oily.