Tach install on 1097A2 w/ 6.5NA

[Josh66]

I’ve looked through posts and tm’s and can’t find a definitive answer. Will this tach work correctly if I splice into the tach drive wires on the back of the engine with the two signal wire lugs? Will it run the hour meter that way if so? Is this the correct way to wire it or is there a better way? The rest of the wiring looks pretty straightforward with switched power, grounds, lights etc. Again the engine is the 6.5 na with the 4L80e trans. Thanks.

 

[Andyrv6av8r]

I installed the same one on my 1045A2 6.5 and it works fine including the hour meter.

 

[JetbikeAnt]

I agree with Andy. Hooked up mine that way as well. Everything works. There are two things I don't like. First, the Tac light comes on as soon as you start the truck. I pulled the hot from the blower switch which was in the instructions. Second, I grounded it to the ground post on the oil pressures switch, again it was called out in the directions. The needle now ticks when the hour meter changes. I would do those parts different if I did it again. I hope that helps,

 

[Retiredwarhorses]

I agree with Andy. Hooked up mine that way as well. Everything works. There are two things I don't like. First, the Tac light comes on as soon as you start the truck. I pulled the hot from the blower switch which was in the instructions. Second, I grounded it to the ground post on the oil pressures switch, again it was called out in the directions. The needle now ticks when the hour meter changes. I would do those parts different if I did it again. I hope that helps,

That’s all incorrect on your wiring

The power for the Tach light comes from the power wire for the instrument cluster lights
The grounds goes to cluster gauge ground
The blower switch is the source for switched power


wired this way, the light only comes on if you turn on the dash lights.

 

[Josh66]

That’s all incorrect on your wiring

The power for the Tach light comes from the power wire for the instrument cluster lights
The grounds goes to cluster gauge ground
The blower switch is the source for switched power


wired this way, the light only comes on if you turn on the dash lights.

Thanks for the replies, I appreciate the information. I was going to wire the rest of the install as per your post (Rwh), found it in another post, which was probably yours. The two tach wires can go to either side is that correct? Thanks.

 

[Andyrv6av8r]

The two tach wires can go to either side is that correct? Thanks.

I tried mine after swapping both wires and it worked either way.