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O2BESOHUGE
07-11-2011, 02:33 PM
I Know This Is Prob A Dumb Question But Here Goes Anyway...why Wouldnt You Just Take Out The Thermostat On The Engine? Let It Run As Cool As The Lake Your In?

Ok- Let Me Have It! :)
Thanks!

mikey.145
07-11-2011, 02:48 PM
I'am sure your joking but, I would imagine it would run great until the engine would start warming up to normal temp,........Then due to un-uniform cooling the heads would probably warp first leading to a serious loss off power then if you pushed on I would imagine the block would crack around the cylinders. Now you just spent more on a new engine then the price of a thermostat.
Fun to joke about but DO NOT try it!

Muttley
07-11-2011, 02:51 PM
Then your engine would run too cold. Heat expands things and your engine is designed to run optimum at a certain temperature to compensate for that. You would lose fuel economy and increase engine wear.

There's also gas atomization, oil viscosity issues...

I don't mean to make it sound like the end of the world, but the bottom line is, if your boat doesn't run between the lines on the temp guage, it will run like crap.

wrobins1
07-11-2011, 02:53 PM
The engine actually runs most efficiently within a certain temperature range and this range is usually higher than the engine would sustain (or even reach) without the thermostat opening and closing. Assuming the engine is under normal operating conditions.

O2BESOHUGE
07-11-2011, 02:56 PM
Well The Reason I Asked...is We Have A 1969 Ski Nautique And Its Been Inthe Family Since Then. My Grandfather Never Ran A Thermostat In It Ever And Its Ran Fine. You Can Ski All Day And Put Your Hands Onthe Exhaust Manifolds And They Are Cool. Have We Just Been Extremely Luck All These Years? IT WAS A CHRYSLER 318 ENGINE WITH 225 HP

I Was Just Wondering

ahhudgins
07-11-2011, 05:18 PM
Well The Reason I Asked...is We Have A 1969 Ski Nautique And Its Been Inthe Family Since Then. My Grandfather Never Ran A Thermostat In It Ever And Its Ran Fine. You Can Ski All Day And Put Your Hands Onthe Exhaust Manifolds And They Are Cool. Have We Just Been Extremely Luck All These Years? IT WAS A CHRYSLER 318 ENGINE WITH 225 HP

I Was Just Wondering

It won't make a HUGE difference on a 1969, but I still wouldn't want my engine running at 70-80 degrees all day long due to the higher engine wear. Once EFI came along, the ECM monitors the engine temperature to adjust the fuel/air misture. The colder the engine the richer it runs....burns more fuel.

kevkan
07-11-2011, 06:55 PM
Engines have changed a lot since 1969. Normal operating temperature today, would have been in the overheating range then. Yes, it is all about efficiency. Better vaporization, better combustion, etc.

Matt L.
07-11-2011, 10:54 PM
My 1990 240SC's 425hp HO454 came from the factory without a thermostat. Runs 140-160 degrees all the time regardless of the lake water temp.

A bit hotter might make it run a bit more efficiently, but it runs perfectly so why jack with it.

Later,

Matt

JimN
07-11-2011, 11:23 PM
I Know This Is Prob A Dumb Question But Here Goes Anyway...why Wouldnt You Just Take Out The Thermostat On The Engine? Let It Run As Cool As The Lake Your In?

Ok- Let Me Have It! :)
Thanks!

Because a cold engine isn't an efficient engine. Go ahead if you want, but be prepared to spend a lot more for gas.

oldairboater
07-12-2011, 12:29 AM
Old race trick was to drill small bypass holes in the round base of our street rod's thermostats. Engines had trouble getting above 180 degrees and if a thermostat failed close the engines never overheated fast. A cold engine is inefficient in fuel burn and might end up with more moisture staying in the oil. That could help cause more acids but frequent oil changes would deal with it. I actually still drill several small bypass holes around the base before installing it into anything I own--including my Mastercraft. My Mastercraft has a 165 thermostat but never gets above 150 unless I run it hard and then idle down quick. All my life I have been told that not running a thermostat will cause hot spots in an engine and harm it. I have never seen proof of that. In my opinion I would always run a thermostat for some heat control. But that is from someone that modifies them.