Overdrive relay test

zoegrant

zoegrant

Well-known member
The Borg Warner book that I have has a procedure to test the OD relay.

it states....with the key on and using a test light hooked to the solenoid terminal of the relay and then to a ground...momentarily ground the throwswitch (THSW) of the relay. The relay will click and the test light will go on & off as the ground is made and removed.
When I do this test the relay does click but the test light does not go completely off, it will dim but not go off.
I am assuming the problem is in the relay because the test light does not go off, it only dims... is this a correct assumption ?
 
It sounds like you have your test light wired into the coil circuit rather than to the two contacts through which you're trying to prove continuity. It almost sounds like the instructions in your manual are deceptively vague. DD
 
DD...not sure what you mean when you say "WIRED INTO THE COIL CIRCUIT" ?
I am not trying to test continuity. I believe the Borg Warner instructions are trying to see if the power is transferred across the relay to the terminal on the relay that goes to the solenoid. Supposedly the shorting out of the throw switch sends power across the relay to the solenoid wire... at least that is my interpretation of those instructions.
I tried to take a picture of the instructions and attach them but not able to do. :(
 
I don't know if you have a problem with the OD functioning. Backfeed currents can be eliminated if you disconnect the governor wire and the solenoid wire from the relay, then try your test.
 
Ok...it appears that all is well up through the wiriing to the solenoid. Tomorrow I will pull the solenoid out to check to see is the solenoid is working or not.
I have had an issue previously with the plunger getting locked into the balk ring assembly and that could be the issue again...I hope not, if so I will pull the ****** and take a look.
I may have to have it rebuilt profesionally.
The ****** is a T86 with R10 overdrive....will post when I have more info.
 
You can test the solenoid in the car by jumpering from the battery to the SOL terminal on the relay. If it's working it should click when you touch the jumper to the battery.
 
Dobbie...I just tried the solenoid test the way you described by jumping from the solenoid connection on the relay (BLUE WIRE) to the negative power on the battery and the solenoid did not engage. The car is positive ground.
Either the solenoid is bad or the solenoid wire is bad or the plunger is engaged into the pawl and wont release.
The last time I had an issue with this I found that the solenoid plunger would engage as it should when the solenoid was disengaged from the ****** and received power directly from the battery...I then thought that the solenoid wire running from the relay to the solenoid was not heavy enough and beefed up the wire to #14 gage instead of the #18 gage that is standard in the harness from the vendors.
Could be a solenoid problem or a ****** problem. I might have to spend $300 for a new solenoid to find out...at least that would be cheaper than rebuilding the ******.
I am open to any ideas....thanks
 
Try jumping from the + battery post. It could be the solenoid isn't installed correctly. If you can remove it without rotating it about 1/2 turn the flat on the plunger isn't engaged with the pawl.
 
Dobie Gillis....I did as you suggested and tried jumping off the + side of the battery and the solenoid did engage....This is a positive ground system so I would have thought that one would need to get power from the neg side of the battery. I do not understand this ?
Can you explain ?
 
You were hooked up to the ground side of the battery, there's no juice there. If you switch to negative ground you would still jumper from the + post. OD solenoids don't care about polarity. In fact most of the electrical devices doesn't care about polarity except maybe the radio and clock. What exactly is the issue with your OD?
 
Dobie...…….please bear with me here. This car is positive ground so the + side of the battery is ground. Correct ??
My first attempt to engage the solenoid was with a jumper wire from the - neg side of the battery because if the + pos side is the ground then the - neg side would be the hot side, correct ?????

My overdrive is not working, could not get my kick down to work so I removed the kickdown switch and found that one of the wires on that kickdown could not be tightened due to a stripped screw hole . I will be installing the repaired switch tomorrow.
I also tried to engage the solenoid from beneath the car using a jumper from the battery to the solenoid directly. It would not engage. So I removed the two bolts holding the solenoid into the ****** and found one bolt very difficult to remove. I got the bolts out and pulled the solenoid to see if it was engaged in the pawl and it was so I put the bolts back in and tested the solenoid again and now find that the solenoid did engage.
I am thinking that maybe the solenoid engaged the pawl slightly off center and I say this because of the extreme difficulty in removing one bolt which I had placed anti seize on. I will road test the car Tuesday to see if OD is now working and will post again.
 
zoegrant said:
Dobie...…….please bear with me here. This car is positive ground so the + side of the battery is ground. Correct ??

Correct. It is very confusing, and Ben Franklin is to blame. Instead of typing it all out I copied this from School for Champions/Scientific:

Current shown opposite

Although the negative charged electrons move through the wire toward the positive (+) terminal of the source of electricity, the current is indicated as going from positive to negative. This is an unfortunate and confusing convention.

Ben Franklin originally named charges positive (+) and negative (−) when he was studying static electricity. Later, when scientists were experimenting with electric currents, they said that electricity travels from (+) to (−), and that became the convention.

This was before electrons were discovered. In reality, the negative charged electrons move toward the positive, which is the opposite direction that people show current moving. It is confusing, but once a convention is made, it is difficult to correct it.

My first attempt to engage the solenoid was with a jumper wire from the - neg side of the battery because if the + pos side is the ground then the - neg side would be the hot side, correct ?????

Nope, the + side of the battery/circuit is always the "hot" side.

My overdrive is not working, could not get my kick down to work so I removed the kickdown switch and found that one of the wires on that kickdown could not be tightened due to a stripped screw hole . I will be installing the repaired switch tomorrow.
I also tried to engage the solenoid from beneath the car using a jumper from the battery to the solenoid directly. It would not engage. So I removed the two bolts holding the solenoid into the ****** and found one bolt very difficult to remove. I got the bolts out and pulled the solenoid to see if it was engaged in the pawl and it was so I put the bolts back in and tested the solenoid again and now find that the solenoid did engage.
I am thinking that maybe the solenoid engaged the pawl slightly off center and I say this because of the extreme difficulty in removing one bolt which I had placed anti seize on. I will road test the car Tuesday to see if OD is now working and will post again.
Click to expand...

When you pulled the solenoid did it just come right out or did you have to rotate it about 1/4 turn? If it came out without needing to rotate it then it wasn't engaged with the pawl. That would prevent the OD from engaging.
 
Dobie...I did have to turn the solenoid in order to remove it.

Thanks for the electrical explanation....
 
You're welcome. Your loose connection at the kickdown switch is likely the cause. The ground signal from the governor passes through it to the relay. If the relay doesn't see the ground signal it won't close and energize the solenoid.
 
Sorry to hear your OD problem came back. I'm curious: if your problem was fixed for a while, how long did it stay fixed?



Could be a solenoid problem or a ****** problem. I might have to spend $300 for a new solenoid to find out...at least that would be cheaper than rebuilding the ******.
I am open to any ideas....thanks
Click to expand...
Just a warning - I bought a new/replacement solenoid and my overdrive still doesn't work. Haven't paid much attention to it in the last few months, though. Unless your solenoid is giving definable traits of being broken, it may be a red herring.
 
Hi Jim...I have a sneaking suspicion that the problem is in the ******. I have at this point tested every part of the overdrive system ..ALL SEEMED TO TEST GOOD ON THE BENCH....Today I will be checking ground wires and then if I do not find anything I will pull the solenoid once more to double check the points in it..
 
If the solenoid plunger rod extends fully when the #4 terminal is powered with the case gounded while bench testing, the solenoid is likely OK. It should extend and retract quickly and with force.

The pawl in the overdrive section should move easily in the passage of the housing. It will only push as far as the balk ring will let it when manually operating it but it should move in and out smoothly. It takes motion of the internal parts to move the gear plate during operation to allow the pawl to go all the way in to one of the notches on the gear plate. If the movement is stiff in the housing that could be a problem. If there is some damage to one or more of the notches in the gear plate, then that could also make it stick. If the lock out rail isn't moving all the way thorough its function range smoothly then there may be some problem with it and the pawl too.

I hope your problem is simple but sometimes mechanical problems do happen.
 
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