The Stovebolt Site Forums The Shop Area The Electrical Bay Neutral Safety Switch

I just put my 50 3100 on the road, have a 350/350 drive train. I need a neutral safety switch but don't have a clue where it's located, assuming there is one. Guidence/advice is as always appreciated

I don't have a TH-350 around right now but I do have a TH-400 and a few TH-700's. I have never seen a neutral switch (or a reverse light switch) on these automatics. I think those switches are often mounted on a steering column or shifter unit (I have a B&M megashifter and it has the switches for reverse/neutral).

UhOh....I didn't see anything that resembled a n.s.s. on the column (69 Chevelle donor) can one be retro fitted? What's the critter look like? :confused:

In my 78 El Camino it was in the column. I do not know what it looks like - I haven't taken it out. If you need it, and it will work, let me know - I don't use it (floor shift)!

- Ryan

Check on the top side of the column tube and see if you have a square cut out section with two 5/16" screw holes on one side of the hole. The neutral safety switch bolts down with the two screws and the lower tab on the neutral safety switch fits into the notched section of the inner tube. The inner section of the tube will rotate when you move the shifter causing the contacts in the switch to make contact when your in Park and Neutral for starting and also in reverse for back-up lights.

Joe

The neutral safety "switch" on most "later" model steering columns (those with the ignition key on the column) is actually a mechanical interlock that prevents the key from being turned into the "start" position in any gear but park and neutral.

I've converted several of these to use floor-mounted ratchet shifters and I've had to fix them in the park position and use the park/neutral switch on the floor shifter to interrupt continuity in the purple wire coming from the start switch in the column when not in park or neutral.

Other than those 2 methods, I'm not familiar with an easy way to do this on a TH350...unless you wanted to get creative and use something like a brake light switch on a bracket near the transmission shift arm. This would allow starting in Park, but not neutral. Something to consider, though.

I fabricated a neutral switch on a Chevy/F*rd conversion, using a microswitch and a disc mounted to the shift quadrant on the transmission linkage at the transmission. I filed a couple of notches in the disk, and mounted the switch so its roller would fall into the low spot when park or neutral was engaged. use the "normally closed" contacts of the microswitch to engage a F*rd solenoid, and trigger the GM solenoid with that one. The GM unit draws too much current to run directly through the microswitch contacts.
Jerry