Wanted: D Type Overdrive

[weathersbubble]

Would love to pick up a D Type (or J Type at a push) overdrive to bolt onto my Herald 12/50 gearbox (3 rail, 3 synchro).

Will be mated to my rebuilt engine with Shorrock Supercharger to keep the RPMs down on a cruise. The more complete (adapter plate, wiring etc) the better.

Does anyone have one for sale? Would probably be best to pick-up but happy to consider a courier too. Based in West London.

Edited August 14, 2022 by weathersbubble
Added info

[RobPearce]

You don't just bolt it on. You need a different mainshaft and a different propshaft, then a different mounting plate and mount. But it's the mainshaft that's the killer - you're actually looking for a complete overdrive box, probably, because that's usually the easiest way to find one.

[weathersbubble]

2 hours ago, RobPearce said:

You don't just bolt it on. You need a different mainshaft and a different propshaft, then a different mounting plate and mount. But it's the mainshaft that's the killer - you're actually looking for a complete overdrive box, probably, because that's usually the easiest way to find one.

Cheers Rob, I'm aware of the adapter plate and prop shaft differences, would you think it best to pick up a complete gearbox already mated to an overdrive box then?

Do you know if there are any differences in the mounting plates for the 3 rail/single rail gearboxes/3 or 4 synchro boxes?

[Clive]

7 minutes ago, weathersbubble said:

Cheers Rob, I'm aware of the adapter plate and prop shaft differences, would you think it best to pick up a complete gearbox already mated to an overdrive box then?

Do you know if there are any differences in the mounting plates for the 3 rail/single rail gearboxes/3 or 4 synchro boxes?

But are you aware of the need to change the mainshaft which needs a complete gearbox strip?

New overdrive mainshafts are available. As are the adapter plates. In fact just about everything is available. At a price!

And yes, there are d type, 3 rail j type and single rail j type adapters. Everything needs to match together. It is rather easier to buy a complete overdrive gearbox, but there is alwasy the worry of how good a used box is. How lucky do you feel?

[weathersbubble]

45 minutes ago, Clive said:

But are you aware of the need to change the mainshaft which needs a complete gearbox strip?

New overdrive mainshafts are available. As are the adapter plates. In fact just about everything is available. At a price!

And yes, there are d type, 3 rail j type and single rail j type adapters. Everything needs to match together. It is rather easier to buy a complete overdrive gearbox, but there is alwasy the worry of how good a used box is. How lucky do you feel?

Haha it's 6 of one and half a dozen of another by the sounds of it - already got the box out for a rebuild so it's not the end of the world about the mainshaft but will see what makes the most financial sense. Will probably rebuild the box (to replace the synchros if nothing else) regardless. Cheers for the help 

[Wendy Dawes]

14 hours ago, weathersbubble said:

Would love to pick up a D Type (or J Type at a push) overdrive to bolt onto my Herald 12/50 gearbox (3 rail, 3 synchro).

Will be mated to my rebuilt engine with Shorrock Supercharger to keep the RPMs down on a cruise. The more complete (adapter plate, wiring etc) the better.

Does anyone have one for sale? Would probably be best to pick-up but happy to consider a courier too. Based in West London.

Me too been looking for one for ages  

like rocking horse poo ! 

 

[PeteStupps]

I picked up a d-type overdrive unit a few years ago and horded it until last year, when I did the full gearbox rebuild and modification for O/D. Buying all the parts separately was expensive: the mainshaft itself was pretty dear but then you also need the right circlips, and the pump drive cam. Then the adaptor plate. Then when it's all together you need the wiring and relay.

Once I'd got everything bolted together, it turned out the overdrive unit was shagged (clutch lining slipped under reverse torque) so I had to remove and buy an exchange unit! It was quite a good learning experience though I suppose...

If I was doing it again I'd look out for a complete O/D + gearbox. It might not end up any cheaper of course.