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TR2/3/3A Overdrive Solenoid Issues

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S

Skidude

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Just took my 59 TR3A on a road trip. Problem was the overdrive did not "kick in" when I flipped the switch. Last time I used the overdrive - it worked - but, was sluggish when kicking in.

Everything I have read about installing a new solenoid is that the piston must be adjusted to keep from burning up. How do I go about making the proper adjustments.

Also, this solenoid is only about 5 years old - almost never driven - and was installed by a British Car restoration shop. Is it common for the solenoids to have this short of a short life?
 
Quick question. Did you check if the transmission was filled to the correct level?

Check the switch, the relay, the wiring etc? Have you checked and cleaned the OD filter?

Just wondering why you are jumping directly to the solenoid?

Cheers
Tush
 
No - I haven't performed any of the checks you mention above - just thought of the solenoid because that was what was wrong the last time the overdrive quit working.
 
I was just messing with my overdrive and did a bunch of research.

Check these things first (because I assumed my issue was the solenoid as well and it wasn't).

First, check the connections with a voltmeter. This isn't usually the first step, but it would have saved me some digging if I had. Then most important is the switch, if you take the switch apart, you'll see it's kind of a funky design. Test the leads by flipping it off and on in second gear (ignition on, car not running).

Also make sure the relays are firing, there are two systems, the first makes sure the overdrive only works in 2-4th gears, the other activates the solenoid. You should still hear a click when putting it an over drive gear (with or without solenoid working).

Finally you can test the current running to the solenoid from the relay. You'll have to look at a diagram to see which wire runs directly to the solenoid, but it should indicate if you're getting power there.

Finally, check the solenoids connections. Especially the ground. Being under the car it sees a bit more grime.

Let us know how it turns out!!
 
You can sit in the car with the engine off - turn the ignition on, turn on the OD and shift into 2nd (or 3rd or 4th) and you should here a loud and distinctive click from the solenoid with each shift. If you hear the click that is suggestive (though not definitive) that the solenoid works. Hear no click and you're on to something.
 
I don't have a multimeter - so, I did as suggested above - I put the car in 4th gear, turned on the key and flipped the switch - nothing. Tried multiple times in third and 4th gear. Also tried a different switch that I had laying around - still nothing. Of course - the other switch could be bad.

Any other suggestions before I bring this up at our British Car Club meeting this coming Wednesday?
 
Could use a test light. 12 volt light bulb and socket with alligator clips on the leads. Ground one lead and connect the other to the wire going to the solenoid then do the same test you just did. That will show you if you are getting power to the solenoid or not.

David
 
Could yet be something fixable w/o removing the tunnel. One thing you might try is to use a jumper to offer 12 volts to the wire to the solenoid.

If you have the stock wiring I believe that wire will be Yellow/Purple.

If you still hear no click then I think the tunnel will have to come off as either the solenoid or a connection has failed.

If you get a click then inspection of the relay and its connections is in order.

As I recall, some nimble sorts may have replaced a solenoid with the tunnel in place, but not me.
 
Do you have to remove the tunnel to replace the solenoid? I just put in a new carpet kit a couple of weeks ago - and that was a real pain. Thought the kit from TRF would go in quickly - took me two days. Hate to remove the new carpet and the tunnel unless it is absolutely necessary. Not sure it's the solenoid yet - just trying to plan ahead.
 
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Went out and purchased a multi-meter and started all the tests recommended above. Like most of you thought - wasn't the solenoid - it was a broken wire. Long, hard painful job when you only know about half what you need to know to jump into something like this - and with no help.

Thanks again for all of your support and suggestions.
 
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Ok, glad you figured it out.

Cheers
Tush
 
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