TheSamba.com :: View topic

Thu Jun 02, 2022 9:30 am

A quick question here.
This tac came in a bug I just got but I'm not sure about the wiring, I don't see any pos or neg markings on it.
I am assuming the flat prong is pos and the round post goes to the coil.

Thanks in advance.

Thu Jun 02, 2022 9:49 am

I wouldn't assume anything. Why not just call them and ask them?

Thu Jun 02, 2022 1:38 pm

That would be my guess. I would put a 9v battery - side on case + side on flat tap and see if it lights. If it does that would be your connection to 58b on your light switch or piggy back from dash lights.

Thu Jun 02, 2022 2:45 pm

I might be wrong, Is there a separate lamp holder?

Thu Jun 02, 2022 4:48 pm

bsairhead wrote: I might be wrong, Is there a separate lamp holder?

Yes there is.

Thu Jun 02, 2022 4:55 pm

My MG buddy says keyed hot on tab coil negative on lug and dash lights on insulated lamp holder and there should be a housing ground or the mounting stud.

Thu Jun 02, 2022 5:08 pm

bsairhead wrote: My MG buddy
Positive Earth?

Thu Jun 02, 2022 5:21 pm

Glenn wrote: bsairhead wrote: My MG buddy
Positive Earth? Nope not all are positive earth. The posters picture even says negative earth.

Thu Jun 02, 2022 5:26 pm

67 on are negative earth

Fri Jun 03, 2022 7:31 am

Found on i-net search...

http://www.mgb-stuff.org.uk/tach.htm

Fri Jun 03, 2022 9:49 am

I think right now you need to decide on it's worth! You don't even know if it works and it's age is very questionable? Where did you intend to mount it? There are 100's of new ones out there that are cheap and have many more options/features!
https://www.summitracing.com/parts/bgs-fst-7906

Fri Jun 03, 2022 10:13 am

RCP Phx wrote: I think right now you need to decide on it's worth! You don't even know if it works and it's age is very questionable? Where did you intend to mount it? There are 100's of new ones out there that are cheap and have many more options/features!
https://www.summitracing.com/parts/bgs-fst-7906 Smith's makes very good gauges and no new one is as cool.

Fri Jun 03, 2022 11:32 am

bsairhead wrote: RCP Phx wrote: I think right now you need to decide on it's worth! You don't even know if it works and it's age is very questionable? Where did you intend to mount it? There are 100's of new ones out there that are cheap and have many more options/features!
https://www.summitracing.com/parts/bgs-fst-7906 Smith's makes very good gauges and no new one is as cool.
The tach is already mounted in the OP's dash. I saw pic of it in the HBB offroad forum.

Fri Jun 03, 2022 3:31 pm

The tac was mounted in the dash when I got the car but I removed everything the previous ( tweaker ) owner had done, I didn't trust any of it.

Anyway I just don't wanna mess this tac up by wiring it up wrong.
And it will be tested before or if it goes back in.

Sat Jun 04, 2022 7:58 am

Worth mounting just for the NEGATIVE EARTH logo!