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A type overdrive question.

donnie

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Greetings to all on the forum, I have a question on A type overdrives. One of my overdrive units is leaking fluid around the seals of the valve operating shaft(part ct 34 in spare parts manual). Does any one know if you can change out these seals without dismantiling the unit? could they be changed in situ?? Thanks Donnie.
 
Some disassembly is involved, but not a whole lot. The solenoid side seal is underneath the solenoid mounting plate, so the plate has to come off. That means removing the lever (and losing the adjustment). You'll need a new gasket for the plate.

On the other side, you have to drill or drive out the pin that locates the 'adjustment' lever onto the shaft and remove the lever.

Whether it's possible in situ depends on which car you are working on. On my TR3, I found that I could get the solenoid plate off by undoing the driveshaft and rear mount, then jacking the gearbox up by several inches. Putting it back together might have been problematic, but since I discovered some serious problems, I didn't find out.
 
Some disassembly is involved, but not a whole lot. The solenoid side seal is underneath the solenoid mounting plate, so the plate has to come off. That means removing the lever (and losing the adjustment). You'll need a new gasket for the plate.

On the other side, you have to drill or drive out the pin that locates the 'adjustment' lever onto the shaft and remove the lever.

Whether it's possible in situ depends on which car you are working on. On my TR3, I found that I could get the solenoid plate off by undoing the driveshaft and rear mount, then jacking the gearbox up by several inches. Putting it back together might have been problematic, but since I discovered some serious problems, I didn't find out.

Thanks Randal for the reply. Looks like I will be trying the replacements some time before spring on my tr3.
 
On my 4A, I can remove the solenoid side plate and replace that rubber seal on the driver's side, as well as the rubber seal on the passenger side, which sits behind the adjustment lever.

I can do that while the transmission is still in the car, but it's tight, a bit tricky getting the springs back in "square," and then you have to reset the adjustment for the operating valve. All of this required that I remove the transmission "hump" cover on the interior of the car. Sort of a hassle.

I now have a pre-drilled hole in the transmission cover where I can slide in the required 3/16 rod for the adjustment lever, but I haven't tested that yet and it may still be difficult going through this process in the future while leaving that transmission cover in place.
 
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