J Type Overdrive
 

Hello All

Stupid Question.

Was given an M41 gearbox with attached J type and told it was working OK. I have connected these up to my B20 and I am ready to drop the engine back in the car.Turning the crank over-the rocker gear,valves etc do what they should. If I slip it into gear I can feel the resistance so assume the gearbox is working OK. But the flange on the overdrive remains static.

Does the overdrive have to be wired up and solenoid engaged to enable the flange to rotate? Don't want to have to fix any problems under the car.

Many Thanks
Brian

RE: J Type Overdrive
 

The short answer is no. If you put the gearbox in any gear and turn over the engine the output flange should turn with it, albeit at correspondingly different rates. The overdrive should have nothing to do with this operation as, when it is not operational as in your scenario, the output shaft should go straight through it to the output flange. If you are certain its in gear and it doesn't turn with the engine something is wrong but it may not be the overdrive, because even when the overdrive stops working you should be able to get the first four gears, otherwise every time one packs in - and they do go wrong - the car would grind to a halt and I've never known that to happen, you just have to live with only four gears till you get it fixed, unless someone can enlighten us both.
Mike Gilbert.

RE: J Type Overdrive
 

The short answer is no. If you put the gearbox in any gear and turn over the engine the output flange should turn with it, albeit at correspondingly different rates. The overdrive should have nothing to do with this operation as, when it is not operational as in your scenario, the output shaft should go straight through it to the output flange. If you are certain its in gear and it doesn't turn with the engine something is wrong but it may not be the overdrive, because even when the overdrive stops working you should be able to get the first four gears, otherwise every time one packs in - and they do go wrong - the car would grind to a halt and I've never known that to happen, you just have to live with only four gears till you get it fixed, unless someone can enlighten us both.
Mike Gilbert.

RE: J Type Overdrive
 

Mike

Many thanks for the reply. There was a phrase you used 'if you are certain its in gear' that made me think - mmm. Now you've got to understand the car has been off the road having a total rebuild for over a year so I had forgotten just how flappy the flappy gearstick is! So anyway you were correct it wasn't in gear (red faces all round) and now the output flange turns in all gears. So now I am a very happy fella - yabba dabba doo.

Brian

RE: J Type Overdrive
 

Im pleased about that, if only 'cos you had me scratching my head for another possible cause. I had visions of you being sold a gear box with half the internals missing.
Mike.