Force 50 Temperature Sensor Location?

[ryguy32789]

Hi everybody,

New boater here. I picked up a 1986 Bayliner Capri with a Force 50 engine this past winter that I plan on taking out this spring, and I've learned a lot from reading through threads on this forum. However, I've got a question on where the temperature sensor is supposed to be. As it sits, it's just taped with electrical tape around the thermostat housing. I feel this can't possibly be right, but then again I couldn't believe these motors don't have air filters either. Any insight on where this thing is actually supposed to go would be greatly appreciated.

 

[ryguy32789]

For some reason the forum won't let me post images, but here are links to a couple.

https://drive.google.com/file/d/0B6M6-6qZEAbuemNsN3JOU241NnM/view?usp=sharing

https://drive.google.com/file/d/0B6M6-6qZEAbuNlBYU1FzejZ2OGc/view?usp=sharing

 

[Frank Acampora]

OK! Here is your problem. That sensor was designed to screw into the head near a spark plug. The previous owner probably broke the screw trying to remove the sensor and tried to improvise.. It should have been glued to a 1/4 -20 bolt with a 5/8 inch head. It appears that he twisted the sensor portion off but it still may be functional.

Now, the way your sensor is taped to the head it will be very slow to react if at all. You can try scraping off a spot on the head and using some JB to epoxy the flat part of the sensor to it.

If it does not work, you can buy an after-market sensor that has a clamp bolted to the head. This clamp holds the sensor in contact with the head. BUT--They are very slow to react.

OHO--On second look, the bolt with the 5/8 hear is still in the top of the head! Try gluing the sensor to it and see if it still works.

 

[ryguy32789]

Ah, now I see where it was supposed to go. Right next to that pipe plug. Does it have to complete an electrical circuit through the motor in order to work? I was thinking instead of glue I should try soldering it back where it's supposed to go. Or maybe conductive epoxy?

 

[Frank Acampora]

OOPS! Yeah--it is a simple bimetal switch. When the engine gets too hot, the switch closes and goes to ground, completing the circuit from the indicator (buzzer or light). So yes, you need something conductive.

The ones I have destroyed for whatever reason, have the bimetal contact just clear of the 5/8 head. The assembly was held together by shrink tubing..Yours seems to be encapsulated and looks a bit different. If it doesn't work, you can get the newer style from Force engines and secure it to the head.

 

[ryguy32789]

Thanks for the advice, would a sensor from a newer Force motor be a plug-and-play setup, as long as I can get that old 5/8" plug out of the head?