Tach test

[bowhawk]

Well I haven't made a lot of headway with the other thread so I'll try a different approah.
Does anybody know how to test the tach on a 62 Hawk?

Life is tough.
It's just tougher when you're stupid.

[N8N]

There was an excellent article in TW about these tachs back in the early 80's, if you have access to back issues. I don't recall which one it is but you can probably find it if you download the TW index off of the SDC site.

nate

[bowhawk]

Thanks Nate,
I just tried to find where to download the text and could only find a list of back issues.

[N8N]

I'll look later (probably much) tonight if I have time and see if I can point you towards it...

nate

[Bud]

I've tested the tach in several 62 Hawks. The tach itself is a voltmeter and will indicate about 6000 rpm if 6 volts dc is applied to its terminals. I used my radio bench 6-12 volt dc to get six volts, but a battery will work as well. If the tach shows an indication, then the sending unit has failed or there a broken wire or something is disconnected. I've never found a bad meter, the failure has been in the sending unit. Bud

[64V-K7]

I have a few notes here...

http://www.studebaker-info.org/rjtechx3.html#Tachometer

[N8N]

Bill,

here's the index

http://studebakerdriversclub.com/tw_index.asp

I'm pretty sure that this is the article I'm remembering

1962-64 Studebaker GT Hawk Tachometer Robert E. McDonald Jr. 12 1 1980 January

(no, I'm not that old, I just collected a set of back issues because for every couple I'd buy I'd find something genuinely useful or interesting like this.)

nate

[bowhawk]

I've tested the tach in several 62 Hawks. The tach itself is a voltmeter and will indicate about 6000 rpm if 6 volts dc is applied to its terminals. I used my radio bench 6-12 volt dc to get six volts, but a battery will work as well. If the tach shows an indication, then the sending unit has failed or there a broken wire or something is disconnected. I've never found a bad meter, the failure has been in the sending unit. Bud[/QUOTE]

I guess part of my question is, with the 6 volts if it reads 5000, is the tach bad? If you test it multiple times and get different numbers each time is the tach bad?

[kurtruk]

I had a '62 Hawk. The tach would frequently get stuck at a certain RPM. It seemed to be a mechanical "stick." Because I could tap on the glass gauge cover and it would free up and swing up to the correct RPM. Sometimes it would stick on the way down. Tapping on it would free it up. I always thought the ring magnet (or whatever) inside had rust or something causing it to drag on something. I did not relish the thought of peeling open the rim of the can. Never fixed it before I sold the car. Did your car ever come from California? Originally Ermine white, then blue? I too have that back issue, but it would take some mighty deep digging to come up with it.

[Bud]

bowhawk, If the tach reads 5000 rpm with 6 volts applied to it, then I suspect that the tach itself is good. The sending unit has an adjustment which will compensate for meter differences. I've seen the meter movement stick in meters because the needle pivot bushings are sticking. There isn't much that can be done about sticky meter movements without opening up the meter and repairing the bushing problem which is best left to someone that is familiar with doing meter repair. The meter movement has extremely fine wire and a spring about the thickness of a hair so one false move and the meter movement can be ruined. Bud