how to test my thermostats?

[bpd119]

How do i test to see if my thermostats are working. 1986 90hp v4. thanks

 

[captain zac]

Re: how to test my thermostats?

If you can get them out
No experience in outboards
Put them into a pan of boiling water and see if they open

Harry

 

[tashasdaddy]

Re: how to test my thermostats?

suspended the in a pan of water with a candy thermometer, should start to open at 140* do not let them sit on the bottom, or you get a false reading.

 

[bpd119]

Re: how to test my thermostats?

ok another question, will water **** out of the pee hole when the thermostats are closed?

 

[tylerr83]

Re: how to test my thermostats?

yes there will be a pee stream even if the tstats aren't opening....that is just an indicator that your impeller is pumping water

 

[HighTrim]

Re: how to test my thermostats?

Ill assume you are having an overheat/no water via the tell tale situation?

When was the impeller last changed? If it has been a few years, change it, along with the t stats, and flush the cooling system, then have a worry free summer of boating. Also ensure that the tell tale water line is not clogged, or the nipple, as little critters love to nest in them over the winter.

 

[bpd119]

Re: how to test my thermostats?

the thermo's were changed last summer, i just changed the water pump and havnt tried it yet. im going to put it in a test tank and see what happens. but last year it wasnt flowing like it should. i will check the nipple and the hose tomorrow thanks for the advise.

 

[bpd119]

Re: how to test my thermostats?

how do you flush the cooling system? is there any certain products to use or just run it in fresh water?

 

[tashasdaddy]

Re: how to test my thermostats?

just water from the hose, i use muffs, rather than a tank.

 

[HighTrim]

Re: how to test my thermostats?

how do you flush the cooling system? is there any certain products to use or just run it in fresh water?

I change my water pump and t stats every 2 to 3 years, and flush the water line while Im at it. I run compressed air or the garden hose up the water line, ensuring it exits at the t stat housing, then back flush the water/air back down from the t stat housing to the water line. Then repeat with 2nd t stat if applicable. This ensures no blockage and free movement of cooling water.

Some may call this overkill, replacing parts (t stats) that may not yet be faulty. I call it cheap insurance. Just build it into my maintainance schedule and in theory will keep you from troubleshooting overheat situations.