Tach drive cross gear install

[Michael M.]

Hi all. I have a 66 L79 with a standard distributor. I recently had to lower the rear of the engine to remove the trans for a clutch replacement. When I tried to unscrew the tach drive cable the entire cross gear assembly came out. The tach functioned perfectly prior to this and the gear looks new. Is it possible to reinstall that assembly with the dist still in the car? Or is it best to remove the dist to reinstall it properly? Thanks for any advice or experience anyone can offer.

Mike

[Michael M.]

Re: Tach drive cross gear install

Let me rephrase that question slightly. I think I can physically get the piece in there, what I really mean is will the gear engage properly without me being able to turn the distributor shaft? I don't want to save the extra work and end up having both gears break and then have to get the shaft rebuilt. That's what I really meant to ask. Thanks!

[Joe R.]

Re: Tach drive cross gear install

Michael,

It should be no problem to reinstall the assembly with the gear and just tighten it down with your hand. Attach the tach drive cable and you should be ready to go. I would put some lube on the tach gear when installing back into the housing. Using axle grease will work fine.

JR

[Michael M.]

Re: Tach drive cross gear install

Thank you Joe. I'm pretty sure I got it. It looks the same as before it came out.

[Chester C.]

Re: Tach drive cross gear install

I've replaced mine a couple times with dist in car. No problem

[Michael M.]

Re: Tach drive cross gear install

Thanks guys. I've read a number of threads about broken gears and I didn't want to go there. My tach was working perfectly and the gear looked perfect also. I didn't want to mess it up.

[Timothy B.]

Re: Tach drive cross gear install

Michael,

Keep in mind that if that distributor has some miles on it there could be some wear inside the distributor housing where the tip of the cross shaft gear and housing thrust is located. This will in time cause misalignment and take the teeth off both gears so in the future you may want to inspect the housing for this.

The repair is simple and will preserve the original parts.

[Michael M.]

Re: Tach drive cross gear install

Thank you Timothy. I'm not sure, but I would bet that my dist was redone at some point. I've done the easy stuff, the points, condenser, cap, rotor, the black wire inside, and the VAC was replaced with the right model (2 inch rule?, I forget)
I had it out of the car when I first got it, 5-6 years ago, to replace a leaky intake manifold gasket. It seemed to be in good order, but I didn't check that deep either. It idles real smooth and the tach is really steady. It's on my list for the future, maybe next winter? It works really well for a 50 yr old dist if it hasn't been redone. Hope I didn't jinx it. Fingers crossed.