T-stats on 110hp rude

[chazbemerry]

I just finished a rebuild on my 1988 110hp evinrude and fired it up for the 1st time and ran it in a barrell of water to test and adjust as neccesary. it had run about a minute or 2 when the overheat alarm sounded. I should of checked the waterpump and t-stats when i had the motor apart. my question i took the waterpump out it looked fine (replacing anyhow) and took out the t-stats, are they similiar to car t-stats? I put the t-stats in hot water and they opened, i plan on changing those also but for future reference, can they be tested?

 

[MCM]

Re: T-stats on 110hp rude

Chaz, t'stats are similar in that they should open at a predefined temperature, (different ranges for different motors). The only method I know of testing is the pot of hot water, you could use a digital (turkey) thermometer to determine at what temp the stat is opening. As for the overheating you may want to investigate the water passage deflectors & check valve, maybe something was overlooked in the rebuild.

 

[Dhadley]

Re: T-stats on 110hp rude

Did you replace the deflectors when you rebuilt it?

 

[chazbemerry]

Re: T-stats on 110hp rude

the deflectors are those platic tubes between the cylnder wall and the crankcase? what purpose do they serve? are they there to slow the flow of water? i can't remember seeing a checkvalve. where exactly is it located? thanks chaz

 

[chazbemerry]

Re: T-stats on 110hp rude

no i didn't replace the deflectors. the gasket set didn't have any new deflectors in it. i can see that on ishopmarine.com they are fairly cheap. I will certainly invest a few bucks for the sake of my rebuild. i'll also purchase a new checkvalve. i still would like to know the purpose of the deflectors. i'm a great backyard mechanic and this is my first outboard rebuild. the motor had a burnt piston, a few scratches on the cylinder but nothing a hone can handle. the engine is i believe a saltwater engine from the salt deposits that i cleaned out of the engine.

 

[ob15]

Re: T-stats on 110hp rude

If I'm correct, they do what they are called. They deflect the water around the cylinders to provide proper cooling. Without them, the water doesn't circulate properly and the motor will overheat.

 

[Dhadley]

Re: T-stats on 110hp rude

Exactly. And if they are swollen, which they most likely are, they can slow down the flow or actually stop it.

 

[chazbemerry]

Re: T-stats on 110hp rude

Thank you all. one final question, my engine has a hose coming off the rear, i'm quessing it's called the bubble back, the exhaust, is that supposed to have water flowing from it when engine is running? again thanks, i am going to replace the deflectors and check valve and will keep you posted at my progress

 

[Bradster941]

Re: T-stats on 110hp rude

This will be a lesson learned for you when you try to replace the check valves. <br />This, and stats should have been replaced during rebuild. What’s the point in doing the job half way?<br /><br />Yes, it should be peeing water. Strong at first when cold, a little less when the stats open.<br /><br />This tip might save you a little aggravation when putting the new ck valves and stats in.<br />Pull the power head off. It will be worth the $10 for a new gasket to avoid the aggravation of trying to work under the bubble.<br />If you don’t want to do that, take the bolts out and drop the lower cowl to give yourself a little room during installation.<br /><br />As a side note, I’ve always wondered why the block isn’t simply machined with a blank at the deflector plugs point instead of using them in the first place?

 

[chazbemerry]

Re: T-stats on 110hp rude

Yes, a lesson well learned. I'm just glad i posted to you guys before i ran the motor for a longer time. thanks again