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Help -think I've got a bad overdrive solenoid ?

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bighealeysource

bighealeysource

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The overdrive on my 56 100M was working perfectly and then out of nowhere it stopped. Have checked all the electrical connections per the trouble shooting guidelines in the works manual as well as articles from Roger Moment. Even put in a new throttle switch since the existing one was the original. Get no response of the desired solenoid clicking but what I can hear- when you simply switch on the ignition,press down the gas pedal and move the gear shift to the right when in 3rd or 4th gear - is a very slight whining like the solenoid itself is trying to move the plunger. Faint but there when you move the gear shift. I am thinking this must be the solenoid and guess I get to remove the tranny tunnel and check it out. From everything I have read on this subject seems like if the electrical tests do not get any results then must be the solenoid has given up the ghost after working just fine the other day. Any other advice ?
Thanks,
Mike
 
You don't need to press down on the gas pedal when you want to hear the solenoid. With the ignition on and the OD switch on, just moving the gear lever to 3rd/4th. It's a definite noise, very easy to hear with no engine running. If you can't hear it then your solenoid is not operating. With the tranny tunnel removed you can check if you get the 12 volts to the solenoid, the other possibility is a bad earth connection to the solenoid.

Ian
 
I had to replace my solenoid, but made the mistake of reusing the original plunger. It didn't work. It was a little too short for the new solenoid. When I switched it out for the plunger that came with the new solenoid, it worked fine. I also had installed an in-line fuse (10 amp). That saved the new solenoid because the old plunger was not long enough to switch the pull circuit to the hold circuit.
 
bighealeysource said:
The overdrive on my 56 100M was working perfectly and then out of nowhere it stopped. Have checked all the electrical connections per the trouble shooting guidelines in the works manual as well as articles from Roger Moment. Even put in a new throttle switch since the existing one was the original. Get no response of the desired solenoid clicking but what I can hear- when you simply switch on the ignition,press down the gas pedal and move the gear shift to the right when in 3rd or 4th gear - is a very slight whining like the solenoid itself is trying to move the plunger. Faint but there when you move the gear shift. I am thinking this must be the solenoid and guess I get to remove the tranny tunnel and check it out. From everything I have read on this subject seems like if the electrical tests do not get any results then must be the solenoid has given up the ghost after working just fine the other day. Any other advice ?
Thanks,
Mike
Click to expand...
Sounds like a bad/weak solenoid. Clicking okay, but not enough strength to do its job. I had the same symptoms...changed solenoid and OD worked.
Patrick
 
Thanks y'all for the advice and confirming what looks like the problem. Ordered a new one from Moss and it comes with a new plunger too so hopefully will not have the problem Tim mentioned. Plus, GREAT idea about putting an inline fuse in the circuit. That I will do !
Many thanks,
Mike
 
Hey y'all,
Thought I would let you know it was a bad solenoid. Installed a new one today and works like a charm. Going to take it out for a test drive to make sure the old plunger works with the new solenoid as Tim ran into and if not put the new plunger in and try again. ALso going to put in that in line fuse, just want to make sure it is accessible without pulling the trans cover !
Thank again,
Mike
 
I hope you didn't misunderstand my experience. I tried to reuse the old plunger and would have burned out the solenoid, or my wiring, because it did not switch off the pull circuit and continued to draw 30 amps or so until the inline fuse I had installed blew. The OD worked once until the fuse blew. I swapped out the plungers using the new one that came with the new solenoid and have had no problems since.
 
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