25 thermostat removal

will941s

Chief Petty Officer
Joined
Oct 1, 2007
Messages
540
This is second of my posts, I removed my thermostat because I want my engine to run cooler....Broke off the bolts (getting fixed as I speak) and as I understand, running without the thermostat will cause no problems. But.....I think the water running through the water jackets maintain some kind of pressure because of the restriction from the thermostat even when it's wide open. If this is true then with the part removed, there is a loss of water pressure in the water jackets that may or may not cause some sort of cooling problem...like some parts being hotter than normal. I was thinking, the thermostat has a removable o-ring, if I get a washer the size of the ring on the t-stat with maybe a 1/4 hole and put the o-ring on the washer and put that improvised part back in the t-stat hole will that help maintain the pressure the t-stat would have created? Or am I just thinking WAY too much into this?
 

JAKER95XR

Cadet
Joined
Sep 29, 2009
Messages
29
Re: 25 thermostat removal

Look at the bottom of this page.Similar threads.Thermostat removal-Did it right? Johnson&Evinrude Outboards from Sept.22nd 2008 there is some real good info.
 

will941s

Chief Petty Officer
Joined
Oct 1, 2007
Messages
540
Re: 25 thermostat removal

Thanks for the direction on the threads.....they were very helpful. I guess I was ont he right track here with the whole pressure deal. I think instead of trying to match the pressure with improvised parts I will just re-install a new t-stat and keep doing so every year. I have to say.....t-stats in salt water make me very very nervous though.....I will def install a temp guage if I can find a aftermarket one for a 1998 merc 25.
 
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