Technical SW tach

What year would the tach be ? No identification #’s and as per the pic does not say RPM

 

Nothing on the back? That's where the ID numbers and letters usually are.

 

Nothing

 

It literally says Revs Per Minute on the bottom, R.P.M.

With that out of the way, it looks like a 1920-30's tach judging from the diameter and the logo. May even be marine or motorcycle. With no markings or serial numbers, it's just going to be a guessing game unfortunately. I would run it if it works.

 

Agree and I should have said, doesn’t say RPM above the center of the needle where the comparators I have found do.

 

I’d guess beginning in the 30’s and up to the 50’s.

 

The needle is different from any SW gauge I can find anywhere.

 

Thanks and appreciate the effort as I am hitting a wall figuring it out.

 

Roger. See if you can compare it to the 8k one I gave Jeremy years ago. It's the same style and needle. I think it still has numbers on the back. Late 40's early 50's as I recall.

 

Thanks Matt.

 

Still trying to figure out approximately what year it is

 

As I said before. The 30’s to the 50’s. They started making gauges for the non-passenger market in the 30’s, and they stopped using that needle in most gauges in 1948 and pretty sure all gauges by mid 50’s. But what do I know?

 

Maybe take a separate pic of it and try a Google image search.

 

Thanks alchemy and appreciate your insight.

 

Yes, Alchemy hit the nail on the head. If there are any numbers on the back, you can tell the year made from the letter/number code. Here's a dating chart & some other old ephemera that you might be interested in seeing. Also, those tachs came in various ratios, as they were used for industry, as well as motor vehicles. Most for the cups had a little plate with the ratio stamped on it...2:1 for tach drive hookup...1:1 for crank hub or generator hookup, etc.

 

Thanks for the wealth of info. I was lucky enough to find a crank tach drive for my flathead.