Tachometer Acting Up

My tachometer started acting up.
At engine idle it would read zero revs and as you slowly open the throtlle the revs jump up to 3500 and then settles around 4000 with the engine probably at 2800 or so which is where we usually cruise.

I looked at the sender unit, pulled the wires off and noted significant corrosion. Cleaned terminal with fine emery paper and sprayed liberally with Corrosion Block. Restarted engine and to my relief the problem was fixed with tach behaving normally.

I am thinking of spending some time with the engine and doing that with all the electrical connections. Sooner or later they will all corrode.

BTW I replaced the oil pressure sensor (very surpising but it was only about $9.50) and the engine oil warning light and buzzer are working normally again.

Trevor Rabie

Dionysus C387 #8
Yanmar 3JH3E


I had the same experience and

You need to be logged in to see the rest of this content.  Catalina380-IA members, please login.

To join please fill out a membership application (Association->Membership Application) and send a check to the address on the form.

1 thought on “Tachometer Acting Up

  1. I checked all wire connections, removed, cleaned and replaced. My Tach does not have a rotary switch, it has 4 dip switches, I cycled them anyway.
    Tach still jumps, I’m considering a new Tach.

    Skip “Bellatrix”
    C380 #43

This site uses Akismet to reduce spam. Learn how your comment data is processed.