Westerbeke w13a running too cool

[mdzito]

Hi Gang, I have a Westerbeke w13a in my Cal 28-2. This year, I decided to replace all the hoses, the impeller, the rusty old water heater, the thermostat, and the water temp sensor (because I broke the old one). The only item that really needed changing was the water heater, the rest was all preventative. Here's my problem. When I first launched the boat, I motored her to her summer port and the temp gauge showed a nice steady 180 degrees as it should. I had nice hot water coming from the fresh water taps.. All seemed wonderful. Next time out, temp didn't go much above 110-120. Seemed odd, but I didn't really run it very long. Yesterday I was forced to motor nearly 10 miles at about 2500-2800 rpm. Gauge still read in the 110-120 range. Hot water is still nice an toasty, exhaust is nice and clean, all seems perfectly fine except the temp gauge is reading too low.

Anyone have any thoughts? I am slightly suspect of the temp sensor because the new one is very different in design than the original, but it did seem fine on my first trip of the season.

Any input is appreciated. Thanks..

[erps]

They have hand held "point and shoot" thermometers at auto parts stores now for under $50. I have one and find it useful for troubleshooting all sorts of stuff. If you had one of those, you could quickly confirm whether the motor was getting up to temperature or not by aiming it at the head and pulling the trigger and then reading the temp.

[mdzito]

Thanks Ray. I think I'll try that. I love buying tools anyhow. Do you think the head temp should ready about the same as the water temp? (hopefully around 180)

Marc
S.V. Nauti-Dog
1987 Cal 28-2
Milford, CT

[tytower]

Lets hope that pinpoints it .
If its running colder than it should then I would suspect a sticky thermostat. They just have a ball of wax in them that heats up and expands.
Next perhaps a faulty temp sender. Perhaps the sender does not match the original and has damaged the guage?

[JimsCAL]

Not likely it could damage the gauge. I'm pretty sure it's just a variable resistor. Checking the temp with a thermometer of some kind (contact, IR, etc) and comparing would be a good first step.

[mdzito]

I'm going to try the ir thermometer this weekend, pull out the temp sensor to take a look at it, and if nothing jumps out at me, maybe pull the new thermostat and put in a 195 degree unit I have in my spare parts. Thanks all. I'll let you know what happens..