Cheap thermostat possibility

[msauntry]

Does anyone know a source for thermostat wax elements?
If there are others of a like mind on this board that love to take things apart and see how they work, read on.

Its seems my thermostat has failed and I'll have to get a new one. I've got the Westerbeke 140 degree version and $140 price tag that goes with it. The thermostat mechanically is fine, but the copper cylinder that contains the expanding/contracting wax element seems to have failed. I took apart the simply constructed thermostat and it looks like I can just press this bad element out and put a new one in. Internet searches turned up a company in China, but I'm not quite ready to put in an order for 100,000 of them.

This part looks like it costs about $.14 and I'm having a hard time swallowing the $140 replacement cost. The rest of the thermostat is fine. I know about the other kits available with spacers and shoulder nuts, but it seems like something us handy A4 types are able to tackle. It might come in handy down the road when manufacturers no longer make our current thermostat options too.

I'll see if WM has some on display that look right and I might pirate its parts for an experiment, but if anyone happens to know where these things are made, that would be a huge help.

For those that are interested, the copper cylinder has a special wax that expands and contracts under temperature changes, causing the thermostat to open and close. I might even be able to replace just the wax if I can get the cylinder apart, then I can pirate any 140 degree thermostat. With the exception of a C-clip, I took the thermostat apart by hand.

I'll keep the board posted on anything I can find out.
Thanks,
Micah

[charles@pricefarrington.c]

T stat

Ok, so it looks as though to get a retro fit to use any aftermarket T stat, you have to spend money to get the retro fit kit, Or, do nothing and spend 140 for an OEM T stat. Is this correct?

[msauntry]

Yes, unless I can find a replacement element. Thermostats are a throw away part in most mechanic's books... If you question its function, simply put in a new one. That's fine if its a $10 part, but at $140 for the Westerbeke, or even $45 for the "cheap" Volvo option, I think its worth taking a shot at other solutions. What's bugging me so much is this part only cost a few bucks to make.

[Dave O]

Thank you for the the technical iinformation about the t'stat. It is interesting.

Personally I would bite-the-bullet and replace the t'stat with the $140 version. I feel the same way about the $ value of a part like this. It seems extremely high. But that cost versus the time/effort to do it at a more reasonable price might be unattractive. I would rather be "safe" with a new stat at $140 than risk a possible cooling problem that may cost quite a bit more and take a long time to solve.

Dave O

[sastanley]

Micah,
I just bought the $140 kit (+ 2 new studs) so I won't have to buy another $140 thermostat - however, my issue right now is time and the length of my project list.

Good luck and keep us informed

[msauntry]

I think WM has a candidate in their Sierra line of thermostats. I'll take a closer look this weekend and see if it indeed matches. I hope to take its 140 degree element and switch out mine. Which reminds me I'll need propane this weekend to boil some water for testing

Its an interesting exercise in that if I need to switch to a 180 degree thermostat with fresh water cooling, I can just find another element and keep using the same thermostat body! I do hope to switch to that next year, so I'd REALLY hate to pay $140 for just a few months of thermostat use.

I realize this is all just theory at the moment, but who knows what may come of it. BTW, I noticed prices for the "cheap" Volvo thermostat are in the $70 range now at other sites. Nobody tell Don... he's got them at $40 something.

[rigspelt]

... Its an interesting exercise in that if I need to switch to a 180 degree thermostat with fresh water cooling, ...)

Before deciding on a 180 thermostat in an A4 FWC system, check out this thread: http://www.moyermarine.com/forums/showthread.php?t=1595

[msauntry]

All the thermostat searches I've done, I've somehow missed that.

Thanks, Rigsy!
-Micah

[msauntry]

Results

Hammer fixes thermostat-- saves $140.

I boiled some water and tossed in my Westerbeke style 140 t-stat and it didn't open. I had already cleaned it off by soaking in vinegar so I thought it was toast and time to experiment.

Out comes the hammer...

I tapped the wax element pin head gently and tossed it back in the water. This time it opened! I repeatedly immersed and cooled it and it seems to operate normally now. I put it in the engine and took a test spin around the creek and the temps held between 165 and 180. Right where I wanted it!

It thwarted my plans of finding a cheap alternative to all our expensive thermostat options, but I'll have to wait until this one really craps out before I can remove its element. I've got a lead on a mechanical engineer who used to work with thermostats and can probably find the right one.