Tach question

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Mar 10, 2015 | 05:29 PM

maytag906

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From: Northern Indiana USA

Tach question

I replaced the non tach instrument cluster in my 84 F 150, with a cluster with a tach from an 86. The tach did not work, but worked when I hooked it up direct before installation.
If II decide to hook up the tach direct, do I need to insulate the leads from the cluster printed circuit? I'm thinking there might be some feedback, or something nasty like that.

Mar 10, 2015 | 06:20 PM

Eddiec1564

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From: Arcadia, Fla

Did your old cluster have the full gauge set and no idiot light for oil and temp?

If full gauge cluster, the swap should be plug and play unless something was changed under the hood.

Mar 10, 2015 | 06:23 PM

maytag906

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From: Northern Indiana USA

The 84 had the gauges, looks similar to the 86 one pictured.

Mar 10, 2015 | 10:09 PM

Jrcrispy2

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There is a plug under the hood that needs to be wired to the distributor. your truck should iirc have a two pin plug on the drivers side near the firewall that has a green and black wire the green wire goes to the coil and the black gets grounded unless the distributor is grounded internally. Your harness should already be wire for it from there to the cluster. Someone correct me if i am wrong on this.

Mar 11, 2015 | 06:25 AM

JimsRebel

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From: Washington

Quote:

Originally Posted by Jrcrispy2

There is a plug under the hood that needs to be wired to the distributor. your truck should iirc have a two pin plug on the drivers side near the firewall that has a green and black wire. The green wire goes to the coil and the black gets grounded unless the distributor is grounded internally. Your harness should already be wire for it from there to the cluster. Someone correct me if i am wrong on this.

"the distributor is grounded internally"
change this to.... unless it it a six cylinder engine.

Jim

Mar 11, 2015 | 02:10 PM

maytag906

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From: Northern Indiana USA

I'll look for it!

Mar 11, 2015 | 06:11 PM

maytag906

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Got it

On the inner fender under the master cylinder, there were 2 connectors that went together, but looked like they had never been connected. One had a black and green wire. Hooked 'em up, the tach worked!

Thanks, all!!