M35B water temperature sender threads

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dpaulo
Posts: 22
Joined: Thu Jul 05, 2007 6:24 am

M35B water temperature sender threads

Post by dpaulo »

Can anyone tell me whether the threads on the temperature sending unit for a Westerbeke M35B are metric or NPT? I'm sitting 6 hours away from my boat and would like to order a replacement sender before I head back. I'm hoping to use a generic sender (with the same temp range) rather than the more expensive factory brand if possible.

All of this is part of a long process of troubleshooting a water temp gauge that acts normal until engine rpm's hit 2000-2100 then starts instantly jumping to the right side of the gauge. In the meantime motor appears to be running within normal temp range, pumping lots of sea water (no steam), no heat "smell", and no high temperature alarm.

I've seen various references to the same issue on several internet sites. The odd thing is that the experienced opinions have all suggested different fixes. Thanks for any input. captain dan
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TBOT422
Posts: 424
Joined: Sun Jun 26, 2011 5:36 pm
Location: Clearwater, FL

Re: M35B water temperature sender threads

Post by TBOT422 »

Dan,

I suspect you can get the proper temperature sensor from many auto parts store that sells Kubota parts. Another thread on this forum seemed to indicate that the M-35B is a Kubota block engine. You may want to read this thread for details http://www.catalina350.net/phpBB3/viewt ... bota#p2987

Good Luck
Gary & Janet
The Best of Times (Hull #422)
Richard Ad
Posts: 58
Joined: Wed Apr 14, 2010 1:08 pm

Re: M35B water temperature sender threads

Post by Richard Ad »

Before you replace the sender try cleaning the wires at the back of the gauge and the bus behind the instrument cluster. Remove one at a time, clean with sand paper and replace, then clean the next one. It worked for mine.
Capt. Nini
Posts: 21
Joined: Tue Feb 27, 2007 11:38 pm
Location: Gatesville Tx

Re: M35B water temperature sender threads

Post by Capt. Nini »

I had what sounds like, a similar problem, that was solved by changing the coolant.
Coolant was old and lost its effectiveness. Be sure to use RED coolant.
Hope this helps
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