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TR2/3/3A Tranny lock out switches

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Tinkerman

Tinkerman

Darth Vader
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I just started a lock out switch ID test. I put the tranny into first gear and checked the switch with my multi meter and I had continuity across the switch. So that one is first and second. Went to the next switch which I figured should be 3rd and 4th. The switch remained open. Tried it several times with the same results. What's wrong? Bad switch? Mechanical problem?
Take the switch out and bench test it?
The car has not been on the road at this point. The tranny is a total rebuild and has been succesfully bench tested.

Your thoughts greatly appreciated!

Thanks, Tinkerman
 
Did you try reverse?

BTW, both switches should be open in 1st gear, so that is wrong as well.
 
Randall, it's a fully synchronous TR 4 gearbox.
Dick
 
Doesn't matter if its TR3 or 4, both sws should be open in first. Same for second for TR4, Third and fourth closed only when in that gear. Switch id probably shorted. Pretty common if original sw (old)

Marv
 
I think that's what Marv meant, but just to be clear, there should be a switch closed (conducting) when in 2nd gear. Only early TR2 and later TR6 (with J-type) should lack the switch for 2nd gear. But none of them should have a switch closed in first gear.

I asked about reverse on the off chance that somehow you have a reverse lamp switch mixed in with the OD switches.
 
"I asked about reverse on the off chance that somehow you have a reverse lamp switch mixed in with the OD switches."
Click to expand...


Randall, I love AHA moments and that was one. That couold be the problem. I am truly flying blind here and didn't know that there was a difference, sigh. I shall check tomorrow.
Thanks, Dick

That's what happens when I get let loose with a little bit of knowledge. Ah well back to the testing and looking tomorrow.
 
The reverse switch is the same, functionally, the only difference is which hole it gets mounted in. It's easy to get the rails confused as well (BTDT). When you move the shift lever to the right for reverse, it actually moves the left hand rail.
 
Dick,

Here's a great picture from Geo showing which switch is for which gears.

ODTop_zps94c20774.jpg


Scott
 
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