View Full Version : temp gauge not working

07-10-2005, 12:17 AM
On my 96 PS190, the temp gauge would work sparatically. Now, it just stays pegged out. I have replaced the sending unit, but that didn't change anything. All the connections in the back seem to be ok. Any suggestions ?

07-30-2005, 01:36 PM
I've just encountered the same issue on my 1995 ProStar 205. So far, I've replaced the sending unit (obtained from local Mastercraft dealer), and examined the wiring from the sensor and behind the guage, both of which seem OK. The boat starts and the temp guage begins to rise slightly, then abruptly pegs to 240 after about a minute and stays there. The motor is not that hot, and the abruptness of the change makes me think it to be electrical. I will replace the impeller and thermostat next (doubt it to be the problem), but the guys at SkiDim think I may have a bad ground wire. How do I go about checking that? Any thoughts greatly appreciated.

07-31-2005, 12:47 AM
here is a quick check; disconnect the wire from the sending unit, then ground it to the intake manifold. Turn the key on and look at the gauge; it should be pegged. If this happens, and you have a new sending unit, then start checking for grounds.

07-31-2005, 07:48 PM
Thanks for the advice! I'll try that when I get back up to the boat this weekend.

08-25-2005, 12:49 PM
Turns out the sending unit was the wrong one---one that screws into the starbord block (maybe for fuel richness...cold start). I have the correct temp. sending unit that feeds the guage now from skidim (part #1234), and will install it at the next opportunity. All the wiring appears to be correct, so I hope the sender does the trick. Seems that there is not enough time anymore to get wet!

08-25-2005, 12:55 PM
What happened to mlange's post on this thread? His post was on-target with what others are saying here. The only thing is that he referenced a thread on the mailbu discussion board.

08-25-2005, 01:02 PM
I don't know. Have not seen them, but sure would be interested!

10-31-2005, 08:29 PM
Well, I finally got it working. Turns out it was a bad guage that I was able to replace from Overton's for about $20. The best help I found for this problem was from the Teleflex website (teleflexmarine.com). It is easy to navigate, and I was led to a .pdf file entitled, "tempsy~1" that is attached. It walks you through the troubleshooting steps in "idiot-proof" fashion to determine a gauge or sensor problem, and includes a schematic of each. Thanks to all that gave advice. Good luck!