Thermostat????

C YENSEN · #1 10-03-2008, 08:21 AM

can I run my I/O without a thermostat? It is a 470 Mercruiser? Why do I need one?

It has a heat exchanger so it has a closed water/antifreeze system for the motor.

Airslot · #2 10-03-2008, 10:44 AM

Motor run be as efficient if it never reaches operating temp. It will run without the stat though. Long term, probably not the best idea. Short term, it'll be OK. Probably cause the motor to run rich...

nipper · #3 10-03-2008, 11:40 AM

Just curios CY as to why you would want to get rid of the t'stat.

spareparts · #4 10-03-2008, 03:41 PM

your really need that thermostat in that engine especially. . The thermostat allows the engien to run at a staedy temp, keeps it from going from cold to hot too fast, It will aslo slow the coolant flow so the heat has time to conduct to the coolant, then transfer that heat when it goes thur the heat exchanger. That thing has an aluminum block, cast iron head, and either an aluminum manifold or cast iron depending on the year model, with all those disimular metals in that engine, it would have all kinds of expansion issues. Most motors run better around 180 anyway, they tend to run marine engines a little colder just to resist preignition and to be on the safe side.

THEFERMANATOR · #5 10-03-2008, 04:34 PM

What SPARE said. ANY marine engine should have a T-STAT in it. If not you will also have moisture problems in your oil. When the engine runs cold it will sweat inside from the heat of combustion, but the cold engine temps. That sweating will cause water to accumulate in the oil and eventually turn it milky. Also not to mention the fact that to get complete combustion you NEED heat in the engine. There is virtually no good reason to run without a T-STAT other than it can't fail if it isn't there. But to have it there does ALOT more than most people think.

cfelton · #6 10-05-2008, 01:17 AM

Hey CY, theres a couple on ebay for sale right now. Check em out.