Tachometer weirdness (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Aug 22, 2019
Threads
37
Messages
1,155
Location
Greeneville, TN
Lately my tachometer either stays stuck or is very sluggish when the outside temps drop below the low 40s. It comes back to life after the truck warms after running for about 10-15min. Not a huge deal, but just seems weird since the tach is going off an electrical signal. Anyone else ever experience something like this?
 
perhaps some old grease in dial? If not a loose connection that closes circuit when warm.
 
Time to upgrade to fancy Speedhut Gauges. I didn’t get a Speedhut Tach as I wanted EGT and boost. I bought a diesel tiny Tach.
BB9D1A8D-BB68-40B6-9E38-3CCB06CBE971.jpeg

6F7ACDC6-D2C8-4810-ACE6-0D6B0E190A42.jpeg
 
Lately my tachometer either stays stuck or is very sluggish when the outside temps drop below the low 40s. It comes back to life after the truck warms after running for about 10-15min. Not a huge deal, but just seems weird since the tach is going off an electrical signal. Anyone else ever experience something like this?

Mine does the exact same thing. Never been stuck, but it is very sluggish until the truck warms up. Interested in an answer as well.
 
I just put in the heavy duty battery cable kit that the guy on here makes, I wonder if one of my connections isn’t tight.
 
Time to upgrade to fancy Speedhut Gauges. I didn’t get a Speedhut Tach as I wanted EGT and boost. I bought a diesel tiny Tach.
View attachment 2201302

If I ever want to work on restoring the other truck, I can't be buying fancy gauges for this one!
 
I just put in the heavy duty battery cable kit that the guy on here makes, I wonder if one of my connections isn’t tight.

My tach acted like you describe when my cables were loose.
 
Not offering any solutions but mine functions when it wants to. That and the temp gauge that doesn't work is suspect? The tach stays up near 1000 then sometimes gets stuck at 2000. Then it works normal when it wants. I think it might be related to heat like yours.
 
Totally unrelated search, but I was reading about speedometer recalibration on a shop's website. They mentioned older gauges may be sluggish in cold weather because of the lubricants they used to use on the needles. Add 30+ years of whatever found it's way inside the gauge and it makes sense I guess.
 
Totally unrelated search, but I was reading about speedometer recalibration on a shop's website. They mentioned older gauges may be sluggish in cold weather because of the lubricants they used to use on the needles. Add 30+ years of whatever found it's way inside the gauge and it makes sense I guess.

I believe the FJ60 speedometer is of the mechanical eddy current variety....basically a couple spinning components nested inside each other with not direct contact. As they spin they basically generate an electrical current that forces a reaction with the wheel the needle is attached to. gobblydeegook aside there is often a fine oil in there to help keep things moving smoothly and over time that oil can dissipate and then your speedometer has troubles...or it might get dirty. Easiest repair is to swap in another speedometer. (Assuming your drive cable is good).
 
Good! I’m not the only one here with this problem.
I was thinking along the same lines as Seth regarding the tach. 30+ of mung clinging to the ancient lubricants.
I have been planning on removing the tach and giving it an alcohol bath in a hydro sonic parts cleaner. then replace the old lube with something that would not attract gunk.
worth a try I suppose. Otherwise it’s pretty worthless now.
 

Users who are viewing this thread

Back
Top Bottom