Yanmar Tachometer

winston1 · Mar 28, 2012

My old tachometer hand sort of moves around and is as much as 200 rpms off depending on speed. This is with checking with cheap digital tach.

I have changed the drive cable and little gear unit because of an oil leak. So I believe the tach itself is the problem.

I have considered removing it and seeing if possible lubrication could help. Probably can't do that. Anybody looked at theirs real close?

May be a little cost prohibitive for me but here is another option. Tiny-Tach: Diesel Tachometers Attaches to the injector line.

Anyone out there tried anything like this. I just have this thing about getting a correct tach reading.

kenmac · Mar 28, 2012

Don't know if this helps

Mine wouldn't jump around . But , the gears inside would some times bind (for lack of a better term) & break the cable. This happened just after I bought the tractor. The dealer wasn't able to repair the original tach. He installed a new JD tach.I liked the original better

clemsonfor · Mar 28, 2012

Mine would bounce around and screech and then not move at all then go back to moving. It all of a sudden totally stopped and started screeching while i was bushhogging one day. I cut everything off returned tractor to idle and jumped off. All it was, was that the cable into the back of the tach needed to be tightened and the bouncing kind of subdued it self. NOt saying this is your problem as you have replaced the line before so im sure you snugged the new one up and still had the problem, maybe this will help others that are reading this thread with a similar problem though.

California · Mar 28, 2012

Mine (on the 186d) screeched and jumped around when I bought it. Lubing and straightening the cable didn't help.

I finally removed the tach and put liquid lock fluid (graphite in solvent) around the shaft where it enters the instrument so a tiny amount went inside. That worked, it has been fine for two years now.

But I think in most cases a replacement tach from Hoye etc is the only answer. I like to keep the appearance of the tractor original, and in conformance to the manuals so that future maintenance is simper to get right.