Yanmar 2GM20F tach

[Glenn Whaley]

I have a deep and abiding need for a replacement tachometer for my diesel. It was broken (pegged at 3100 rpm) when we got the boat. There is electrical signal getting to the console/back of the guage. There is no mfr/OEM listed on the guage itself. It has a magnetic pickup, a max range of 4000 rpm, and I can't find a replacement. Any ideas, anyone? I do have a lead on a Teleflex tach that may serve, but it's max range is 3500 rpm and the Yanmar maxes out above that (~3650). Don't know if you can over-drive a tach and bust it or not. Thanks.

Glenn

[Inlet Marine Services]

Yanmar makes the tach still and you can purchase it from your local dealer, max rpm is 3600

[Northeaster]

See the link below for Teleflex guages. I just ordered a new magnetic pickup tach for my Yanmar 2GM, as it never came with one. Make sure you get a magnetic pickup one, as I was sold the wrong model Teleflex last year, and it was for use with the alternator, but not magnetic pickup. New one cost approx $130

They may have more than one model, as they have different product ranges!!


http://www.teleflexmarine.com/docume...002_5_1049.pdf

[S/V Antares]

VDO made a lot of the early tachs for Yanmar which work off a mag pickup located on the bellhousing. the output is 127 pulses per rpm (It counts the flywheel teeth).

Your problem is that it is likely 80mm diameter. Most replacements are 85mm or 100mm.

There are many tachs available in 0-4K range but may not fit the hole. Check out Aetna, VDO, Faria, Murphy.

[billangiep]

I believe that the tach. and the magnetic pick up need to match... GM = 97 flywheel teeth.... LH = 127 teeth.... SERVICING the ENGINE