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Overdrive doesn't work at all

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wlivesey

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Hi everybody, My overdrive has always worked just fine (over 5 years) - no problems at all. Then all of a sudden there was no response. I have checked the electrical and I am getting power to the solenoid when I am in 4th gear. I changed the transmission oil (somewhere I heard it may just be dirt). By the way, I took that opportunity to change to Red Line MTL. I even tried adjusting the Throttle Switch. Is there anything else I should be checking? Does it sound like the solenoid itself needs replacing? I would appreciate it if someone could give me a little more direction.
Thanks, Bill
 
Is the solenoid actually pulling up? If it is check that the lever on the opposite side of the transmission is rising to the alignment hole. If it's properly adjusted there is probably an internal problem.
 
The solenoid doesn't seem to be doing anything. Should I hear something if the solenoid was pulling up? Right now I don't hear or see anything (of course, I can't see much since I barely have enough space to clear my nose!).
Thanks,
Bill
 
Take the trans cover off if you haven't already. This will allow you to assess the problem close up. The solenoid will click loudly when engaged and should not to be mistaken for noise from the toggle switch. Do you hear this noise? The OD lever located on the other side of the trans opposite from the solenoid should move back and forth (back to front) when the solenoid is engaged. Check for operation and correct adjustment.

Also check for interference from something like the speedometer cable

PLease don't drive the car in reverse if the solenoid is stuck and O/D engange. Damage may occure. Good Luck. GONZO
 
Thanks for the advice, but that Solenoid seems dead as a door nail. No sound at all and no other movement detected. Am I safe to assume a new solenoid is necessary?
Thanks
Bill
 
Bill,
This is one of the best references on OD trouble shooting. This particular one covers the "type A" which is what you have. Note that there are four previous sections that really get into things. This last section will give you some ideas about general electrical & control problems.

https://www.buckeyetriumphs.org/technical/AOD/AOD5/AOD5.htm

Note that your car has an additional throttle switch whuch is not present on the triumph. To duplicate these tests, remove one of the the wires on your throtte switch. The switch mounted on the firewall that is linked by a rod to the throttle linkage.
D
 
Wlivesey, Disconnect the solenoid feed from the switch and momentarily connect it to 12 Volts if it clicks its ok if it does not its"Dead as a doornail"-FWIW---Keoke /ubbthreads/images/graemlins/laugh.gif
 
The solenoid has two windings, a winding that draws about 20 amps to pull it in with high force & a separate winding that draws about 2 amps to hold it in.When the solenoid reaches full upward travel a contact under the top rubber cover opens to deenergize the pull in winding. If this contact is dirty, burned, or not working , the pull in winding will never operate the solenoid. If this contact doesn't open the solenoid will draw 20 amps continuously & burn up in short order.
D
 
Hey thanks to everyone for the help. And Dave, thanks for the buckeye link, it was very helpful.
It turns out the rubber cap on the selonoid was in very bad shape. The contacts under the rubber cap were extremly dirty. Once they were cleaned up, the OD was working again. Does anyone know if I can buy a new rubber cap anywhere??
Thanks again,
Bill L
 
Moss catalog shows it as unavailable. Victoria British only lists the solenoid complete with cover, no separate cover or boot.
 
Bill L, perhaps you can find one of those plastic boots which are used to block off unused vac lines that is large enough to use on the solenoid. I know they make them that large ,but you may have to hunt a bit to find one.-or ask Inan at Healey Surgeons to get you one they have a lot of spares- FWIW---Keoke
 
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