60 series tach in my 40

[aktundra]

As I hammer out this posting, it occurs to me, i probably need to post this question in the 60 series forum.

i am working on installing a 60 series tach, in my 1980 FJ40, with a basically stock drive train (2F)

bought a 60 series tach for $20 from a local parts yard. Dug out the bullet connector left empty in the OEM harness, got wiring from past posts here in the forum.

here is my dilemma. If just wire things in, with the tach on the fender & give the idle a little rev. the tach does not move, then jumps to 2k, seems to fluctuate reasonably from there on up. but gradually decrease the revs, and just under 2k, goes dead again.

im wondering if this is a known issue with old 60 series tachs, or is the issue with my connection in a 40 series harness ? anybody been down this path ?

 

[MOTOV8R]

I have a 60 series tach in my 40. It works normally. Maybe a bad tach?

 

[franklin40]

not a diesel 60 series tach is it? they don’t speak gas. they have a different signal from the injection pump

 

[Living in the Past]

not a diesel 60 series tach is it? they don’t speak gas. they have a different signal from the injection pump

Believe diesel have a magnet in the flywheel and a switch on the bellhousing that is used for RPM.

 

[franklin40]

i guess maybe there are different ones? i was thinking of the 1hdt (thought not a 60 engine). i guess the 12ht, the 3b and 2h may be different and have flywheel signal but they may still be a different signal pattern that the tach cant read. the gassers read off a coil and the flywheel sensors are a hall sensor and have a different electronic signal. so i dont think any of the diesel ones whether pump or flywheel will talk with the gasser

 

[mattressking]

What did you wire the tach to? 60 series tachs aren't known to have dead spots, so I'm curious how you wired to your truck.

Red is tach signal, Black and Green 12V and Black is ground.

Is yours connected correctly?