61 generator and tach drive lube

[Gordon W.]

I just had my tachometer rebuilt and the needle bounces under heavy load. I'm trying to diagnose and was wondering if the gears in the generator need to be packed with grease? See this picture: IMG_20121126_214745.jpgs Also, the ST-12 shows to lube generator every 1,000 miles with engine oil. I'm guessing it's via the tube I'm holding with my finger in this picture. My question is how much oil do I put in there? Fill til it comes out the top? Does this lubricate the gears in the tach drive? IMG_20121126_214814.jpg

[Joe M.]

Re: 61 generator and tach drive lube

Have you lubed the tach cable with powdered graphite? If the cable grabs a little inside the steel sheeting, it will cause the needle to bounce; eventually it will make a lot of noise then the cable will twist up inside the sheething and snap. Cable lube will prevent this. It doesn't take very much of the nasty, messy graphite to do the trick.

[Jim D.]

Re: 61 generator and tach drive lube

Use a thin coat of Lubriplate on the gears, a few drops of oil down the tube and clean the tach cable and re-lube it using Vaseline.

[Gordon W.]

Re: 61 generator and tach drive lube

Have you lubed the tach cable with powdered graphite? If the cable grabs a little inside the steel sheeting, it will cause the needle to bounce; eventually it will make a lot of noise then the cable will twist up inside the sheething and snap. Cable lube will prevent this. It doesn't take very much of the nasty, messy graphite to do the trick.

I used KableEase (I think that's what it was called) to lube the cable before I had the tach rebuilt. The little bit of black grease you can see in that gear housing is from the cable lube.

[Gordon W.]

Re: 61 generator and tach drive lube

Use a thin coat of Lubriplate on the gears, a few drops of oil down the tube and clean the tach cable and re-lube it using Vaseline.

Thanks, so a thin coat rather than pack the whole thing with grease. Okay, glad I asked before I did anything.

I hope this solves the needle bounce but I am not expecting it to.

[John H.]

Re: 61 generator and tach drive lube

I just had my tachometer rebuilt and the needle bounces under heavy load. I'm trying to diagnose and was wondering if the gears in the generator need to be packed with grease? See this picture: [ATTACH=CONFIG]43012[/ATTACH]s Also, the ST-12 shows to lube generator every 1,000 miles with engine oil. I'm guessing it's via the tube I'm holding with my finger in this picture. My question is how much oil do I put in there? Fill til it comes out the top? Does this lubricate the gears in the tach drive? [ATTACH=CONFIG]43013[/ATTACH]

Gordon -

Oiling the Gits tubes on the generator is only necessary if it still has the original non-sealed bearings in it; most, if not all generators have long since been rebuilt with modern sealed bearings that don't require any lubrication.

[Joe L.]

Re: 61 generator and tach drive lube

Thanks, so a thin coat rather than pack the whole thing with grease. Okay, glad I asked before I did anything.

I hope this solves the needle bounce but I am not expecting it to.

Gordon-----


It probably won't help but it's worth a try. In any event, it constitutes regular maintenance which is always a good thing.

Most times, needle bounce is caused by a fault in the instrument, itself. While Corvettes through 1974 use a mechanical tachometer, it's not a direct drive type (e.g. like that used on some race cars). It uses a "mechanical/magnetic" damping mechanism and that's where the problem often lies.