Tachometer Not Working 

I don't know anyone who rebuilds these to work off the positive feed anymore, but my go to for converted factory tachs is Rocketman's Classic Cougar Innovations. Despite the name, he converts tachometers from all kinds of older Fords. I've used his converted tachs in three cars now. The oldest has been in place for over a dozen years, the newest for almost four, and they all still work perfectly.

Hi. The neutral safety switch will stop the car from cranking but not stop it from running. The faulty tacho will stop it from running but it will still crank over

Neutral safety(red/blue) and ignition(red/green) are two totally different circuits with separate feeds from ign switch. Think about it, if starter circuit were hot with engine running it'd never disengage. I'm sure some of those voltage tachs have failed but I'm yet to see it. Better chance someone connected it to negative side of coil. I have seen a Mustang II with a nonfunctioning tach but it ran OK. Found it had a shorted transistor. Replaced with another, that one quit in about a week. Again, same transistor was shorted. Replaced that transistor and replaced aftermarket coil with Motorcraft, no more issues.

Thanks for this information Jeff. I will be installing a new wiring harness in a 67 Mustang along with an Intellitronix digital gauge cluster. This is good to know before starting the install so the connections can be verified without having to go back and re-do.

I am a Ford fan but I’m not inspired to believe Ford tachs are much more accurate than negative run tachs aka… all the others. Sorry Ford. Thanks for the tips here. Great channel!

Another awesome informative video. Great job!!

Fixed alot of no start mustangs etc "back in the day". Real popular in the high-school parkin lot.....

I did a OEM tach conversion from idiot lights in my 71 Mach 1 utilizing a non tach harness. I have a bypass wired in in case the tachometer ever fails.

If it fires while cranking but doesn't run when the key is released to the run position it is most likely an 'open' tach and is easily bypassed under the dash without cutting and splicing. Anyone with a factory tach Ford product into the 80s should carry a 3-4" jumper wire with a female bullet connector on one end and a male bullet connector on the other. Disconnect the tach, insert your jumper into the connect(s) that you took the tach leads out of and viola! the car will run. It should be noted that the 67/68 models actually came with a jumper as part of the circuit. If the car just plain refuses to turn over, THEN check the neutral safety switch. As far as repairing a Ford 'in-line' tach goes, Phidon is the only place I trust to fix one. Of course if your tach has a plastic case (late '69 into '70 and beyond) it is a Faria epoxied stacked magnet POS and cannot be repaired - it's a miracle any made it through the 36 month warranty. If it has a metal case chances are it is a Bendix built unit with a very solid D'Arsonval movement. Again, if you don't want to convert you metal cased tach but want it original, contact Phil at Phidon.

The spare tach that's not in a gauge cluster is bad if I remember right. So is the voltmeter

Hey Jeff , Is this cluster tach the type that won’t work with the Pertronix III Ignitor kit from an earlier episode ? In my ‘ 64 Galaxie I have a dealer installed Rotunda steel cupped tach mounted at the bottom of the dash ( has a padded dash ) . Will the Rotunda work with the Pertronix III ? Keep up the good work , I enjoy your videos.

Palo Alto Speedometer or North Hollywood Speedometer.

"The Tach Guy" fixes them

Tachman ?

It would explain the saying “Found On Road Dead” was conjured up because of the way Ford designed their tachs in their vehicles back in the 60’s and 70’s. How stupid.