Tach not working

[captkidd]

Well it's Monday and time for everyone to post the boat problems they experienced from the weekend. I have bad news and good news and then more bad news.

Bad news 1: Impeller went out while on the lake Saturday.

Good news 1: Had a spare and tools in the boat. Replaced it in about 15 minutes (darn thing was hot). Many thanks to all who posted suggestions for doing this, especially to the person(s) who suggested using dishwashing liquid (aka binding slime) to make it easier to get the new one in. I admit that I have been slack and had not replaced it in awhile, so it was overdue.

Bad news 2: Tach isn't working properly. It doesn't go below about 800 RPM even when engine is off, and won't go above about 3000-3100 RPM regardless of how much the engine is revved (the engine is definitely turning higher RPMs, but tach isn't registering correctly).

Good news 2: If it can be easily fixed, someone on here will know how to do it. This is the second tach that I've had. The first one went out with only about 40 hours on the boat and was replaced under warranty. Is there anything I can check on the engine, behind the dash, etc., before pulling the tach and ordering a new one (if it can still be ordered)?

Any info will be greatly appreciated.

[JimN]

Make sure the connections on the grey wire at the coil are clean and tight. If they are, connect a wire from the base of the distributor to the block at a place where you have clean metal. If you see it go back to normal, you need to clean the base of the distributor so it grounds better, since that's where the coil(-) need to connect through the points.

[bcampbe7]

What about a tach that operates normally but does not go to zero when off? My `96 PS190 does this.

[Kell]

bcampbe7,
Mine does the same thing and I questioned my dealer about this and he said it was normal and just turn the key to the "on" position (not the "start" position, and the needle goes to zero. I don't know if this is a problem or not, but the solution works.

[John B]

My 96 PS 190 does the same thing,but I never look at that tach I used one on the PP :D

[bcampbe7]

Yeah, it goes to zero when I turn the key to the "on" position.
I have heard from more people (I guess every one I have asked that has it) that PP is the best option they have or have installed on their boat. May be moving up my "want" list.

[DrNautica]

Good news 2: If it can be easily fixed, someone on here will know how to do it. This is the second tach that I've had. The first one went out with only about 40 hours on the boat and was replaced under warranty. Is there anything I can check on the engine, behind the dash, etc., before pulling the tach and ordering a new one (if it can still be ordered)?

Any info will be greatly appreciated.


Captkidd,

Ditto on what JimN said regarding the coil wire and distributor. If you do need a new tach, check out greatlakesskipper on e-bay before going to your dealer. If you don't see it on their site, call them and ask. I just ordered a new tach and two new Sammy Duval Speedos. Price was outstanding and they are brand new units.

[Bert]

captkidd, i had that problem once, turned out to be a poor ground. mine was the grey wire at the coil as JimN has suggested

[captkidd]

Thanks for all the good information. I will check it out as soon as I can and let you know the results. I've said it before and I'll say it again, the wealth of knowledge and experience on this board never ceases to amaze me.

[captkidd]

Well I finally had a chance to check my coil but I can't find a grey wire. It has two connectors on the coil, each with two wires coming from it (neither is grey). I pulled these and checked for corrosion but both looked clean as a pin. Where does this wire connect to the coil? My engine is the 275 hp, 350 EFI (throttle body), which I probably should have mentioned earlier.

[JimN]

Look at your tach and you will see a blue(lights), a black(ground) and a grey wire. The tach lead on the gauge comes from the ECM. The ECM gets RPM info from the distributor(purple/white, AKA Ref High) You can do a do a continuity test from the coil grey connector, white wire to the tach lead.