check ball style t-stat housing -what are the balls for?

[fishingdan]

I have a 1991 4.3lx mercruiser. I'm troubleshooting an overheat problem. While poking around, I see I have the t-stat housing type that has the check-balls on the lines that are connected to the exhaust elbow.

What is the purpose/function of those check balls? With the t-stat housing off the boat, should the check balls be snug against the nipple? Mine have a gap on one end or the other.

Thanks

 

[jerryjerry05]

Re: check ball style t-stat housing -what are the balls for?

That's to make sure the water only flows one way!! Don't remove them.J

 

[cadunkle]

Re: check ball style t-stat housing -what are the balls for?

The check balls restrict water flow to the risers, ensuring enough cool water will flow through your engine block. I had an overheat problem I couldn't figure out for a while. Eventually I thoroughly cleaned the thermostat housing and check balls and stretched those springs out to put more tension holding the check balls.

Symptoms I noticed while engine temp climbed was risers were cool to the touch. I also had plenty of water flow out of the exhaust.

 

[fishingdan]

Re: check ball style t-stat housing -what are the balls for?

Thanks for the responses. When I look at the t-stat house out of the boat. Should both balls be snug to the nipples? I suspect yes. If that is the case, I probably need to disassemble, clean it and adjust it. Currently, 1 ball has a gap between it and it's nipple when the other ball is snug.

 

[Bondo]

Re: check ball style t-stat housing -what are the balls for?

I suspect yes.

Ayuh,... That's Correct...

 

[fishingdan]

Re: check ball style t-stat housing -what are the balls for?

Thank you