Tach "gauge"? problem

woodster · Sep 14, 2015

check all the wiring from the tack all the way to the alt and also check your ground wire as well ...you have a loose or shorted wire some where....95% of the time....

Capt jgw · Sep 14, 2015

The tach is driven by the alternator. If the batteries are fully charged and there's no electrical load, the alt won't put out and the tach won't read. The tach coming on momentarily on start makes sense. The alt put back the starting amps then shut down again. If it does it again, try turning on an electrical load and see if the tach comes back on. Of that doesn't do it it's probably the wire from alt to tach. Assuming this is a Universal diesel, does it still have the original trailer plugs in the harness? They are very problematic and are best removed, running the wires direct.

KZW · Sep 14, 2015

Check the ground wire on the starter solenoid. Mine slips off occasionally and gives the symptoms you describe. When it slips off it makes contact to start the engine, but the engine vibration moves it, driving the tach crazy.

buddybear · Sep 15, 2015

Had a similar problem on our last trip. Opened up the engine instrument panel and found the wire running from the Tachometer gauge to the terminal strip was corroded, could not loosen the screw holding down the wire, the wire actually pulled out of the terminal strip with the screw tightened down as far as it would go. Cleaned and reinstalled wire works fine now.

pk104 · Sep 16, 2015

I replaced the terminal strip with a new one but it is no better. Had a recent problem were after changing a light bulb for the volt meter the engine wouldn't start and found a wire pulled loose but still in the connector. I thought I was careful not to let the panel hang on the wires. A better way to connect all the wires is needed or a better strip connector then I used. The wires aren't long enough to connect direct. Perhaps ring connectors on a strip would be better but it would need covered to prevent shorts from occurring. There are 22 wires that go to that strip plus one not connected to anything. A lot of work to change it.

buddybear · Sep 17, 2015

I have 2001 Hull#57 and the engine panel is not one that the operators manual shows. On the panel it says Catalina Type A high efficiency panel, I haven't been able to get a wiring schematic for it. My understanding is that the engine in this boat is a M25xpbc and the c stands for the type of engine panel, if anyone has any more info on this I would appreciate it. Hope you worked out your tach problem. I agree the terminal strip is not the best way to go, you need to see the condition of the wiring.

So Cal Gary · Sep 22, 2015

Clydo said:
Anyone had this problem? My boat 2003 year. Happened once
before (several weeks ago) and now once again. Started eng tach
needle jumped to about right position then immediately dropped back
down to zero and stayed there regardless of any eng rpms.
Did this for several starts. Then next day started eng and tach
worked just fine. When problem started checked wiring to alt but
could not find any loose wires or connections. Belt had proper
tension. Alt starting to fail?

Clyde Thorington
C310 # 245
ILEAN TOO
San Jose, CA

I had a similar issue a few years back. In my case I opened up the instrument pod to get to the back of the tachometer. On the back there is a selector switch. I moved that selector switch a few times back and forth and then set it back to its original setting (as evidenced by red paint seal that had to be broken). That was enough to clean up the internal switch contacts and the tachometer works fine again.
If that doesn't do it, you can contact Dennis Igarashi at 562-699-7997. Dennis bought/took over the electrical part of Seaward some years back when Seaward was bought out. He can supply most of the electrical panel and parts that are used on our C310's.