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thermostat temp question

Posted: Mon Aug 04, 2014 12:39 pm
by mikeandanne
Well after changing out the temp gauges it seems the engines are running way too cold,130 to 140 with the heads barely making 155.I would like to get some more temp and maybe burn the fuel better .I have not pulled them yet so we shall see what is there if any.

What is everyone using for thermostats for freshwater boats with raw water cooled 318's and 360's ---thanks Mike

Re: thermostat temp question

Posted: Mon Aug 04, 2014 2:09 pm
by g36
raw water cooled 140
freshwater cooled 160

http://www.hurrikain.com/Chrysler-Thermostats.htm

Re: thermostat temp question

Posted: Mon Aug 04, 2014 7:43 pm
by fishernut
After many years I was able to find the 140's which was stock on my 1980 F-25 w/318 raw water cooled. They have been working just fine, running 140-150 instead of 165-190 with the replacement 165. There must have been a reason they were originally installed. Glad I was able to find them. :D

Re: thermostat temp question

Posted: Mon Aug 04, 2014 8:29 pm
by Big D
If you want to run a little hotter, you can run 160 in a fresh water RWC application, wouldn't do it a salt water.

Re: thermostat temp question

Posted: Mon Aug 04, 2014 10:29 pm
by mikeandanne
Thanks guys for the replies----I removed both thermostats and they are 142 deg. original mopar

Tested them on the stove with ir gun and they opened ok but once opened they stayed open down to 130---I will give the 160's a try to see if the head and oil temp gets more in the acceptable range----remember I am in fresh water on Georgian bay,we had 160's in the old boat and it was ok

Re: thermostat temp question

Posted: Mon Aug 04, 2014 11:24 pm
by larryeddington
discussed this item a long time ago with bob and maybe prowlerfish. It seems the low temp is to keep a raw water system from reacting with the salt in sea water if used in saline sea water. I would seem to me that using a higher temp tstat would not cause any accelerated chemical reactions if you were running with raw fresh water. IMO

Opinions?

Re: thermostat temp question

Posted: Tue Aug 05, 2014 8:46 am
by todd brinkerhoff
larryeddington wrote:discussed this item a long time ago with bob and maybe prowlerfish. It seems the low temp is to keep a raw water system from reacting with the salt in sea water if used in saline sea water. I would seem to me that using a higher temp tstat would not cause any accelerated chemical reactions if you were running with raw fresh water. IMO

Opinions?
I have heard the same thing. Higher temps boil the salt water and leave salt residue in the crevices of your cooling system. Higher thermostats for the FWC systems, or operating at higher temps in fresh waters should not be a problem. I have heard the most efficient operating temp for the my 454 is about 195. I have 160's for my 454.

Re: thermostat temp question

Posted: Tue Aug 05, 2014 11:55 am
by RWS
I ran 180 degree thermostats in my FRESH WATER cooled Crusader 454's in Florida waters with no problems.

The engine is simply MORE EFFICIENT at the warmer temp.

RWS

Re: thermostat temp question

Posted: Mon Aug 18, 2014 5:29 pm
by proudfox
I must agree with the 180 Deg. as this is what the manufacturers suggest for best engine performance.

Re: thermostat temp question

Posted: Mon Aug 18, 2014 10:21 pm
by captainmaniac
I bought a new set of Sierra t-stats through marinepartsource.com a few years back, then after I got them realized they were 160°. Since I am raw water cooled and specs called for lower temp for raw water (and the 160's for fresh), threw them in a box and found a pair of 140° to install. Cost of return shipping meant it didn't make sense to try to return them. I was going to sell or give them away, but are you saying the 160°'s are truly safe (maybe even better) for me to use in my raw water cooled Chrysler M360Bs on the Great Lakes? If so, YAY - spares!

Re: thermostat temp question

Posted: Tue Aug 19, 2014 6:07 am
by RWS
proudfox wrote:I must agree with the 180 Deg. as this is what the manufacturers suggest for best engine performance.

===============================================================================================

with fresh water closed cooling systems.

yes

RWS

Re: thermostat temp question

Posted: Tue Aug 19, 2014 12:47 pm
by proudfox
Chrysler 360 ENGINES WITH FRESHWATER/Anti freeze cooling with Heat exchanger using Raw sea water, run best at 180 degrees F. Your antifreeze water routes through engine block and returns thru heat exchanger to have the excess heat removed and then back the engine, regulated by the thermostat. The raw water has no thermostat or other controls, and generally is not much warmer than 60 to 85 degrees depending where you reside from spring through summer.

Re: thermostat temp question

Posted: Tue Aug 19, 2014 1:00 pm
by proudfox
I should also add, you must check your raw water strainers every month or so, if you have the clear glass/lexan ones, no big deal to view, and by all means, every time you use boat look at your exhaust discharge water flow to insure you are having a good continuous water flow. Then every 5-6 years on average, assuming you do not go thru really dirty water, seaweeds ect, pull your heat exchangers and soak it in container with appropriate acid that is safe for your heat exchangers metals to clean away any growths or deposits.

Keep your antifreeze up to snuff, and insure all hoses are in good non leaking condition with (two) Stainless steel hose clamps at both ends of hose..

Boats cannot be left to their perils, maintenance is absolutely required more than a car or truck, you have two water pumps, and the raw water pump impeller is only good on average for years depending on how much you use boat, cooling water pump is usually good for 5-8 years, all of these components may last longer or shorter depending on water conditions, the cleaner the better, so watch your gauges, if engine is warming up, look into the cause and correct it immediately, or you will destroy your engine.

Re: thermostat temp question

Posted: Tue Aug 19, 2014 9:27 pm
by Big D
captainmaniac wrote:.....are you saying the 160°'s are truly safe (maybe even better) for me to use in my raw water cooled Chrysler M360Bs on the Great Lakes?
yes

Re: thermostat temp question

Posted: Tue Aug 19, 2014 9:45 pm
by proudfox
Further explanation and OPINION, 180 IS BETTER THAN 160, but not by a great deal, 180 will burn less fuel, and even 190 even less, but 160 is low, 180 is best, but you need not worry, it will not harm your engine, so boat, enjoy yourself, and have a great Wed, In my opinion.