thermostat temp question
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thermostat temp question
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
What is everyone using for thermostats for freshwater boats with raw water cooled 318's and 360's ---thanks Mike
Re: thermostat temp question
1997 CARVER 405
"the BLACK PEARL"
past fleet
1978 F32 SEDAN CHRYSLER 318's
current fleet
1997 seadoo gts
1997 yamaha wave venture
1985 sunbird 18 ft runabout
1968 coronado sailboat 25 ft
sunfish
14' hobie cat
canoe
8ft portabote
"the BLACK PEARL"
past fleet
1978 F32 SEDAN CHRYSLER 318's
current fleet
1997 seadoo gts
1997 yamaha wave venture
1985 sunbird 18 ft runabout
1968 coronado sailboat 25 ft
sunfish
14' hobie cat
canoe
8ft portabote
Re: thermostat temp question
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. 

Re: thermostat temp question
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.
She was a 1969 36 ft wooden beauty with big blue 440s that we'll miss forever.
And thanks to the gang, 2012 Trojan Boater Of The Year
And thanks to the gang, 2012 Trojan Boater Of The Year
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Re: thermostat temp question
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
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
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Re: thermostat temp question
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?
Opinions?
Larry Eddington
1984 F-36 Tri Cabin "The Phoenix II"
1978 F-28 "The Phoenix"
Fish Master 2350 Bay Boat
9.5' Dink
1984 F-36 Tri Cabin "The Phoenix II"
1978 F-28 "The Phoenix"
Fish Master 2350 Bay Boat
9.5' Dink
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Re: thermostat temp question
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.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?
1991 Trojan International 10.8 Meter Express hull# 003 - 454 Crusaders
1961 Century Raven 22 - Gray Marine 327

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1961 Century Raven 22 - Gray Marine 327

http://s1086.photobucket.com/home/Todd_ ... hoff/index
- RWS
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Re: thermostat temp question
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
The engine is simply MORE EFFICIENT at the warmer temp.
RWS
1983 10 Meter SOLD after 21 years of adventures
Yanmar diesels
Solid Glass Hull
Woodless Stringers
Full Hull Liner
Survived Andrew Cat 5,Eye of Charley Cat 4, & Irma Cat 2
Trojan International Website: http://trojanboat.com/
WEBSITE & SITELOCK TOTALLY SELF FUNDED
Yanmar diesels
Solid Glass Hull
Woodless Stringers
Full Hull Liner
Survived Andrew Cat 5,Eye of Charley Cat 4, & Irma Cat 2
Trojan International Website: http://trojanboat.com/
WEBSITE & SITELOCK TOTALLY SELF FUNDED
Re: thermostat temp question
I must agree with the 180 Deg. as this is what the manufacturers suggest for best engine performance.
- captainmaniac
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Re: thermostat temp question
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!
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Re: thermostat temp question
proudfox wrote:I must agree with the 180 Deg. as this is what the manufacturers suggest for best engine performance.
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with fresh water closed cooling systems.
yes
RWS
1983 10 Meter SOLD after 21 years of adventures
Yanmar diesels
Solid Glass Hull
Woodless Stringers
Full Hull Liner
Survived Andrew Cat 5,Eye of Charley Cat 4, & Irma Cat 2
Trojan International Website: http://trojanboat.com/
WEBSITE & SITELOCK TOTALLY SELF FUNDED
Yanmar diesels
Solid Glass Hull
Woodless Stringers
Full Hull Liner
Survived Andrew Cat 5,Eye of Charley Cat 4, & Irma Cat 2
Trojan International Website: http://trojanboat.com/
WEBSITE & SITELOCK TOTALLY SELF FUNDED
Re: thermostat temp question
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
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.
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
yescaptainmaniac 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?
She was a 1969 36 ft wooden beauty with big blue 440s that we'll miss forever.
And thanks to the gang, 2012 Trojan Boater Of The Year
And thanks to the gang, 2012 Trojan Boater Of The Year
Re: thermostat temp question
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.