The Ford Barn

markdtn · 08-04-2025, 07:56 AM

I have a Ford 8N tractor with an 8BA V8. It was in a 2N in my Avatar but I have since swapped it to an 8N over last Winter. the 2N did not have a place for a tach but the 8N had a "proofmeter" that was like a mechanical tach. Since I can't do that, I wanted a tach with an hourmeter that kind of looked like the proofmeter. So I bought one on Ebay that was a marine style. It was an open box, old shelf stock. I hooked it up and the hourmeter worked but the tach never went over 1000 rpm. Chalked it up to bad tach. Then I bought a cheap offshore tach on Amazon. Same thing, never over 1000 rpm so I sent it back. Finally, I bought a VDO marine tach. Brand new. I have verified the settings, 4 stroke, 8 cylinder, and correct pulses (it actually came out of the box set up like that). The instructions from VDO show hooking to a coil (- of course) but don't exactly address points type ignition. Just FYI I am running a stock Loadmatic distributor with some NOS 1990s Ford points and condenser. I am running 12V negative ground with an alternator. It has a 4-post Motorcraft starter solenoid so it gets 12V for starting to the coil and has a ballast resistor for normal running. The engine runs fine and has since 2017 with no changes to the distributor. Starts instantly when it's warm. Last I checked-but it's been a while-I was getting a reasonable value for RPM with an old Sears tach/dwellmeter.

Anybody else have trouble with modern tachs not reading with points? Any suggestions on what I should be checking? Thanks!

08-04-2025, 07:56 AM	#1
markdtn Senior Member Join Date: Jun 2016 Location: Chattanooga, TN Posts: 164	Modern Tach won't work with points? I have a Ford 8N tractor with an 8BA V8. It was in a 2N in my Avatar but I have since swapped it to an 8N over last Winter. the 2N did not have a place for a tach but the 8N had a "proofmeter" that was like a mechanical tach. Since I can't do that, I wanted a tach with an hourmeter that kind of looked like the proofmeter. So I bought one on Ebay that was a marine style. It was an open box, old shelf stock. I hooked it up and the hourmeter worked but the tach never went over 1000 rpm. Chalked it up to bad tach. Then I bought a cheap offshore tach on Amazon. Same thing, never over 1000 rpm so I sent it back. Finally, I bought a VDO marine tach. Brand new. I have verified the settings, 4 stroke, 8 cylinder, and correct pulses (it actually came out of the box set up like that). The instructions from VDO show hooking to a coil (- of course) but don't exactly address points type ignition. Just FYI I am running a stock Loadmatic distributor with some NOS 1990s Ford points and condenser. I am running 12V negative ground with an alternator. It has a 4-post Motorcraft starter solenoid so it gets 12V for starting to the coil and has a ballast resistor for normal running. The engine runs fine and has since 2017 with no changes to the distributor. Starts instantly when it's warm. Last I checked-but it's been a while-I was getting a reasonable value for RPM with an old Sears tach/dwellmeter. Anybody else have trouble with modern tachs not reading with points? Any suggestions on what I should be checking? Thanks!