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got the car back

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69tr

Jedi Trainee
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Well, sort of.

I brought the tub home the other night. The paint looks great.
The other parts are finished and I need to go get them soon.
I would like to sort a few things out first.

The PO by passed the OD inteupter switches and relay. The relay works but the interupter switches are a bit iffy.
I found a problem with the wiring on the column switch. I rewired the circuit according to the schematic in Bentley manual and I still have a problem. I think there is a ground in the circuit to the column switch.

With the wire to the interupter free the relay still operates when the switch is operated the relay works. I gave up about midnight I didn't want to tear in to the switch at that time.

Oh well, I have all winter to get it all sorted out. I will probably bore everyone with progress (or lack of) reports.

I will try to post pictures soon.

Pete
 
We love pictures?

Here is a nice picture from Shawn's neck of the TR woods.

hiking3.jpg
[/img]
 
69tr said:
With the wire to the interupter free the relay still operates when the switch is operated the relay works.
Click to expand...
I'm sure this warning has been done to death, but JIC you haven't heard : Be very careful not to backup with the OD solenoid powered. It will do some expen$ive damage.

Although I can't prove it, I suspect the J-type is particularly easy to damage, since it may not be engaged when you start to backup (even though the solenoid has power) but will engage when it builds pressure. By then the inertia of the car will be enough to break the sprag clutch and the tailhousing.
 
I finished wiring the OD circuit this afternoon. It is working as advertised now.

Thanks for the warning about backing up in overdrive but it is a little late. I did this soon after I bought the car.

I knew nothing about this type of overdrive. I parked with the car in OD and went to visit. When I got back in the car I just started to back up to get out of the parking space. Fortunately I did not keep trying when it did not move. I don't guess I did any damage because I have driven the car quite a bit afterward and did not notice any thing or hear any funny noises. I did make sure that I did not do that again.

Sometimes luck is better than smart, Pete
 
Is there a lock out on the later O/D's so it will not be engaged in 1st, 2nd, and reverse?
 
YES !
They all have lockouts for 1st & reverse. Some work in 2nd & some don't (all J-types don't).
 
If the factory wiring is intact, yes. Not really a "lockout" from the mechanical point of view. More an engagement concern for the relay. On the trans top cover there are switches for the o/d(along with the reverse switch) These switches need to be engaged before the o/d relay will close the circuit and engage the solenoid.

Again, the caveat, IF THE FACTORY WIRING IS INTACT(or replacement wiring following the factory hookup.
 
Usually, if something is awry with the J-type overdrive and indeed it stays engaged, attempting to drive in reverse with the OD engaged will cause considerable damage. The good news is, if this is the situation, and one were to turn the engine off, the pressure will bleed down in time, about 20 minutes, and the car will go out of OD and can be safely driven. This is not a fix, just a condition. My new J-type from Quantum had this happen where I did indeed run the car in reverse with the OD engaged, unbeknownst to me. What a heart-stopping sound it made! The whole thing, tranny and all, went back to Quantum to have a new J-type installed. Not a pretty sight.
 
The factory wiring was not intact but my trusty Bentley manual got me out of trouble.

The good part about the A type is that it will not operate unless you have power to the solenoid. Unless the relay sticks closed, the OD will not engage without power.

Pete
 
Actually, there are failure modes that can cause an A-type to engage without the solenoid. For example, there is a relatively small orifice that bleeds off the pressure to shift to direct drive. If that orifice gets clogged, the OD may fail to disengage. And if the operating valve(ball) is leaking as well, it may even engage on it's own.

And both A and J types can potentially get mechanically jammed in OD (although it seems more common with the J-type, possibly because it's pressure regulator isn't as robust as the A).
 
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