D type overdrive repair

[kin74]

I recently bought a Spitfire Mk4 gearbox with D type overdrive to fit on my Spitfire Mk2, I have it tested and while the gearbox is in great conditions the OD get stuck. It's not the typical solenoid problem, it works, so I need to contact an expert who could fix it.

Do you know anyone to suggest?

[Pete Lewis]

Have you removed the spool valve under the cap plug on the top face this has a very small hole down its centre, if blocked the pressure is not released when you disengage the solenoid   on removing the screwed plug cap  catch  the spring , ball and small plunger, the valve tube sits below all this , just pull it out    there two reputable manufactures in the uk  that doesnt help if your in Italy

 

Pete

 

 

 

 

 

 

[kin74]

Pete, 

I brought the gearbox to a Triumph expert here, he tested it on the work bench and realized that after the solenoid engaged the main shaft get stuck. He checked the filter and possibly did to the test you suggested (didn't asked actually, but I quite trust him) but with no result. Then he suggested to send the od to an expert because he was afraid to not be able to work on it... and maybe he just didn't want to do further tries.

I'm aware that I'd need to send it to UK and I'm fine with this, up to now I've been suggested to contact Overdrive Repairs and Mike Papworth.

[Pete Lewis]

www.odspares.com/

 

https://www.overdrive-repairs.co.uk/

 

they are not hard to strip and examine  

buckeye triumphs gives good details , not specific D type but exellant detail on many parts 

http://www.buckeyetriumphs.org/technical/technical.htm

 

and https://www.uniquecarsandparts.com.au/how_it_works_laycock_overdrive

 

and  MPap    both very  good

just the cost of shipping

[Velocita Rosso]

Overdrive Services would be my choice, they are pure specialists and will do upgrades to improve eg stronger springs etc

If you have ....ogni problemi, sono vicino questa compagnio, 20km da qui

[kin74]

Thanks for your support, it's very appreciated!

I dropped a message to the suggested companies and waiting for a reply, I'll let you know.

[Matt306]

I brought a pair of D Type OD to make one decent one from. I took it to OD Spares in Rugby. Very knowledgable and helpful. I realise being in Italy this wont help but they know what they are doing. They manufacture many parts and sell them to other companies to re sell.

When you say stuck, is this stuck in or wont engage. 

OD are quite easy to rebuild, there are quite simple really. The pump is driven off the MS cam, which generates oil pressure. The solenoid opens a valve to let the oil press two pistons forward to engage the cone clutch against the brake ring and the OD then engages. Solenoid drops out and the reverse happens.

I found a 22mm pipe fitting will assist in removing the pump.

If the OD is of unknown origin it could be a host of things, from worn seals around pistons, pump not working, pressure not holding (they can be shimmed) Bearing knackered... I would open her up and have a look.  Could simply be a bit of metal blocking a small oil passage way, compressed air will sort that. I would budget for a clutch, seals and bearings. The planet gears bearing will be probably shot too as they get oil starved due to a plate on the end of the fitting. It can run with out this plate.

[kin74]

Quoted from Velocita Rosso-

Overdrive Services would be my choice, they are pure specialists and will do upgrades to improve eg stronger springs etc

If you have ....ogni problemi, sono vicino questa compagnio, 20km da qui

I sent you a PM.

[Velocita Rosso]

Quoted from kin74-

Quoted from Velocita Rosso-

Overdrive Services would be my choice, they are pure specialists and will do upgrades to improve eg stronger springs etc

If you have ....ogni problemi, sono vicino questa compagnio, 20km da qui

I sent you a PM.

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