Sunbeam Alpine Gearbox Problem

[Skoorbydoo]

Hello from Australia. I've a 1964 Sunbeam Alpine Series IV Manual with a reverse gear problem. I can reverse out of my garage successfully, drive a few hundred yards and I've got no reverse. Wait ten minutes and reverse is back. drive home and again, no reverse. It gives a slight vibration like a slipping clutch (or like a gear that's not quite in). Clutch is okay. Can spin the wheels in reverse. Get the usual grating noise if I try to pull in reverse with no clutch.. gear lever appears to pull in okay and does not bump out easily. It seems like an "hydraulic lockout" problem!!?/ I haven't tried draining the oil, flushing and refilling yet. I've had this car for five years and done thousands of miles. this is a new problem. Weird! Anyone experienced it or got any ideas?

[bolide]

Has your car got overdrive? Check it is not engaged

In contemporary Triumph models the overdrive was locked out in reverse as it could not run backwards

Nick Froome

[WJNB]

Contact the UK Sunbeam Alpine Owners Club via the Forum.
There are members with experience of Alpines since they were launched in 1959 & there is not a problem unknown or cannot be solved.
Seek advice from Chris Barker who has written a book on Alpines & has owned the same one for decades.

[eldar]

Skoorbydoo said:

Hello from Australia. I've a 1964 Sunbeam Alpine Series IV Manual with a reverse gear problem. I can reverse out of my garage successfully, drive a few hundred yards and I've got no reverse. Wait ten minutes and reverse is back. drive home and again, no reverse. It gives a slight vibration like a slipping clutch (or like a gear that's not quite in). Clutch is okay. Can spin the wheels in reverse. Get the usual grating noise if I try to pull in reverse with no clutch.. gear lever appears to pull in okay and does not bump out easily. It seems like an "hydraulic lockout" problem!!?/ I haven't tried draining the oil, flushing and refilling yet. I've had this car for five years and done thousands of miles. this is a new problem. Weird! Anyone experienced it or got any ideas?

I had a similar problem with that box a long time ago. It was a loose retaining bolt that located the gear cluster on the main shaft that allowed excess movement of the cluster meaning 2nd, 4th & reverse were difficult to engage consistently.

I can't remember the exact details, but it involved box removal and doing the bolt up properly.

[Skoorbydoo]

Thanks Nick. My car has overdrive but I disconnected the wiring to try a fix. Hopefully disconnecting wiring overrode overdrive???? no difference.

[Skoorbydoo]

Thanks WJNB. Will chase up Owners Club.

[RichB]

Skoorbydoo said:

Thanks Nick. My car has overdrive but I disconnected the wiring to try a fix. Hopefully disconnecting wiring overrode overdrive???? no difference.

If it's the overdrive it's because the cone gets stuck in the 'on' position so disconnecting the solenoid would have no effect. If you can drive forward when you have no reverse see if the overdrive is engaged in every gear, sounds odd because you'll say it's only got overdrive on 3rd & 4th but you should be able to tell by 1st and 2nd being unusually high geared. If that's the case then it's the overdrive physically stuck in the engaged position.

p.s. Google 'overdrive cone stuck problem no reverse' or a combination of those words...

Edited by RichB on Saturday 28th July 09:08

[Ardennes92]

I would definitely go with the saoc forum, helpful lot with contributors from down under, could be someone local to you! there is also a FB page but not always the best as a technical archive

[WJNB]

Ardennes92 said:

I would definitely go with the saoc forum, helpful lot with contributors from down under, could be someone local to you! there is also a FB page but not always the best as a technical archive

As a Life Member of the UK SAOC my response was of course biased but the technical resource & knowledge within the club is second to none.
PM me if you need more personalised info.

[Skoorbydoo]

Thanks All for your input. i have emailed the SAOC who hopefully have an answer.. Re the suggestion of a stuck overdrive cone, I've noticed no difference in forward gears. Everything appears quite normal but I'll read up on it anyway. Chhers

[dikkie]

Sounds an awful lot like the outer clutch surface on you overdrive unit is slipping. Even with with od disconnected you need that clutch surface to hold the planet gears stationary...

I had the same happen on my Jensen (which had a d type overdrive unit from a rapier)

[WJNB]

Please tell me that the SAOC club responded to your email.

[Puddles of Oil]

There are a series of five comprehensive videos that cover the total strip down and rebuild of a Sunbeam Alpine gearbox and overdrive on Youtube. The gearbox is used on numerous Rootes cars and many models used a Laycock De Normaville overdrive so this is really useful information.

Here is the link to part one.

https://www.youtube.com/watch?v=eIP6mBDl6CA&t=...

Puddles