water temp with inboard motor

montymbad

Member
Hey guys, what kind of water temps do you get off your inboard motor. I have raw water cooling, so I imagine that it wont get very hot at all. I was thinking of putting in a heat exchanger, for a couple reasons, one is the couple times a year I plan on running salt water, plus I think it would be less corosion in the motor. And I was thinking of putting in a auxilliary heater I have kicking around. I was going to run coolant hoses up to the front of the cab and mount it there. That way I can run my boat earlier in the year and later in the fall, with out freezing my balls off. Any thoughts? Thanks, Ryan
 
Engine temp should be around 195deg farenheit regardless of type of cooling. The thermostat controls the temperature. It is important to maintain this temperature for proper combustion and efficiency.
Good idea on the exchanger and the interior heater.:D

IMG_1445.jpg
 
quote:Originally posted by Gunsmith

Engine temp should be around 195deg farenheit regardless of type of cooling. The thermostat controls the temperature. It is important to maintain this temperature for proper combustion and efficiency.
Good idea on the exchanger and the interior heater.:D

IMG_1445.jpg

I think 195 is on the high side of the operating range -- mine is usually about 150-160 -- I have the Mercruiser heat exchanger (MPI Horizon it's called). True that it's less prone to corrosion and the closed system is a little safer if you lose an impeller (takes longer to overheat). I have still added in a fresh water flush port to the raw water side and use Salt Away after every trip. Keeps the riser and manifold cleaner.

Here is a good article: http://www.blogsharp.com/news_9734.html

TenMile
<'((((><
 
I have fresh water cooling on my 302 ford and it runs at 160-170 F. The thermostat is a 165 degree thermostat. I would think that will determine what your engine will run at. I'm not sure what raw water cooled engines run at.
 
twin 4.3 vortecs. fresh water cooled. both run at about 165
1 runs thru a cabin heater and the other a hot water tank.

a total MILF.Man I Love Fishing
 
According to The majority of those who hang out at marineengines.com the freshwater(heatexchanger) motors should run a 165 thermostat and the raw water cooled usually run a 140.
 
My motor has FWC but does not have a thermostat(takes a little longer to get up to temp). I bought a IR handheld thermometer from CT. Love that thing to death. Just put the red dot on any spot on the engine, rad, hoses, manifolds, etc, to see temp variances.
Intake manifold runs hot at 39c, but most other surfaces are in the 33-36c temp range. Raw water is usually around 7c. Unit has old fh temp setting too.
Easy way to check for blockages in the FWC system.
 
Originally posted by Gunsmith

Engine temp should be around 195deg farenheit regardless of type of cooling. The thermostat controls the temperature. It is important to maintain this temperature for proper combustion and efficiency.
Good idea on the exchanger and the interior heater.:D


You should get that fixed if your temp gauge is accurate,(most arn't). Salt cristalizes at 190deg ferinhiet. Risers & manifolds(if raw water cooled)won't last long at that temp.

I'm setting my priorities. I'm making time for fishing.
 
I was only using an auto motive standard. Irregardless if the engine runs at too low a temp the combustion is incomplete. Most fuel injection systems need a hotter temp to run efficiently.
Opinions are like rectums everybody has one.:D
Re: Operating Temperature
Is it a fresh water cooled or raw water.Raw water should be down 145-165 fresh water is closer to 180-190.Sounds like your guage has you close to the hot mark.The manifold will be hotter than the riser.If you split the riser from the manifold hopefully you did not use too much sealant on the gaskets.That would make it run hotter.Get the $20 telflex guage at any west marine or boaters world.Change the sending unit too.Charlie
IMG_1445.jpg
 
After reading this thread I double checked the temp of my Ford 460 with American Turbine jet Pump today while fishing for catch and release sturgeon on the Columbia. The river temp was 40 degrees F. {I got one "shaker" a 35" nose to tail fork sturgeon on a smelt. It too line and swam away after one pic.} The engine has fresh water & antifreeze cooling//heat exchanger. It ran at it's normal operating temp. of just under 175 degrees....I'm guessing at 160 - 165. The heater was appreciated all the same while under way.

What I need to do and have on my 30 item "to do" list is to install a warning beeper of some kind to let me know if the temp goes above 200. That temp gauge can be mighty quiet and yet still climb too high if the fan belt breaks or the sand trap becomes clogged. I always carry a spare belt and suggest everyone replace theirs anually. The sand trap situation is predictable and now, when I pull into a beach, I usually kill the big motor to prevent it idling in the shallow water asap or I go in with the 9.9 kicker while folks unload beach gear etc.

thanks,

CW

Any suggestions on such a warning temp. signal? How do I install it and the sensor?

Satisfaction: 23' Aluminum Thunderjet with Ford 460 salmon fishing the Columbia River
 
Back
Top