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Newby with overdrive issues

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Sleeperx7

Sleeperx7

Freshman Member
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Hi all, I'm new to this forum and I have a '63 TR4 with a rebuilt tranny and aftermarket overdrive that doesn't work... so here's what I've checked so far:

The solenoid is moving when I turn the OD on, so the wiring does work. I think the throw distance is correct... the holes line up. I am going to do a pressure check tonight and will post the results. It is my understanding that I need at least 400psi for the OD to engage.

I'll refresh this post with pressure results, but any other suggestions to try?

Many thanks.

Anyone autox their car? I'd like to build the suspension to handle some fun twisties.
 
Welcome to the forum Sleeperx7

If ya want some of the best advice, contact:

John Esposito in Connecticut direct:
?john@quantumechanics.com

Phone 203-459-9612 evenings and Saturday
Fax 203-261-8497

John G. Esposito
Quantum Mechanics Ltd.
505 Wheeler Rd.
Monroe, Ct. 06468
www.quantumechanics.com
 
Yes, welcome to the forum. Tell us what type of overdrive you have; A-type, J-type etc.
 
What do you mean by aftermarket overdrive unit? You should have an A type overdrive.

Go to https://www.vtr.org/maintain/tr6-overdrive.shtml for some guidance

Most problems are electrical, but you seemed to have eliminated this. Next would be low oil. The tranny and OD share the same oil and the OD requires proper volume and pressure to accuate. You might try draining and refilling as a relatively cheap solution. Also do a search on this forum for "overdrive" There's lots of good info out there.
 
Take a drive with the transmission cover off. Manually move the lever on the passenger side of the overdrive to see if it will engage. If it does, your throw distance is not correct.
 
Should take a lot less than 400 psi for it to engage; the higher pressure is needed only to ensure it doesn't slip at full throttle in 2nd gear.

"Lining up the holes" is NOT accurate on all units, regardless of what all the manuals say on the topic. Check out the article at
https://www.buckeyetriumphs.org/technical/AOD/AOD4/AOD4.htm
near the bottom for an alternate method of adjusting the solenoid that always works. There are also some very good troubleshooting tips at
https://www.buckeyetriumphs.org/technical/AOD/AOD5/AOD5.htm
 
Problem fixed, thank you all for the tips. DougF and TR3driver, you guys were dead on, I pushed the lever farther and the OD kicked in. Car's up and running very comfortably now.

I'll post some pics of the car in your gallery sometime in the next few days. If anyone's in the northern Va area there's a great car show this Sat called 'Summer Thunder' in Purcellville. Easily a few hundred nice cars.

Thanks again, I'm sure I'll be posting in the future. Talk to you folks soon.
 
Welcome and remember
"don't look into the light"
 
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