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I rebuilt the Rochester Carburetor on the wife’s ‘79 and was trying to get the settings right when the tachometer suddenly did this and stayed there
anyone else have this happen and can offer suggestions
When working on the carb, you were real close to a canister looking device that is the Tach Filter. It looks similar to a condenser.
Look real close at the wire connections. Sometimes only a few strands of bare wire are attached.
A soldering gun will fix that. I think you lost a GRD somewhere for the Tach to peg.
Had the needle not moved w/ IGN key then likely no power. When a gauge pegs, it has power but poor GRD.
Okay, it was a good day! This morning I took the connector loose between the Tach filter and fire wall, hooked a meter to it and got no reading at all, no change in the tach without it connected. I ran a wire direct without the filter and… no change in the tach, then I reved the engine up and the tach dropped down and seemed to be working (thanks interpon)
I hooked it back up with the filter and it’s working but I don’t trust that it is accurate so I’m thinking I’ll just go ahead and replace the filter.
Before purchasing a new filter do a ohms check.
Your current filter should read around 15.5k - 15.6k
Here are readings of a new replacement filter and a used replacement filter...
And keep your plastic connector housings, they will need to be reused with a replacement filter.
when I put an OHM Meter on it I got no reading at all
Originally Posted by bmotojoe
Before purchasing a new filter do a ohms check.
Your current filter should read around 15.5k - 15.6k
Here are readings of a new replacement filter and a used replacement filter...
And keep your plastic connector housings, they will need to be reused with a replacement filter.
Tachometer
