View Full Version : Normal Operating Temp

03-09-2008, 10:36 PM
Whats everyones normal operating temp? I was hovering at 180 most of the day......Does that seem hot?

03-09-2008, 11:43 PM
180 with a carb. at the end of march and april it usually runs about 140 with the water temp.

03-10-2008, 07:26 AM
I have 06 lsv with 325. Put new impeller on last weekend and rode last sunday afternoon. I always thought mine ran a little high at 175-180..
I believe that both the gauge and the thermostat are not precise enough that they are dead on. I am of the opinion of if it does not go above that, it is just a calibration issue. I have a 5.3 chevy in my truck that runs 210 all the time. these run cooler because there is no need to put off heat..
Unless this is a change in what your boat used to do, you should be fine.
If it is change, check impeller to make sure it is healthy. Mine was perfect when I took it out, but changed anyway..


03-10-2008, 03:30 PM
Dumb question any good manual on checking the impeller? I never did one (my first inboard) I dont even know where it is

03-10-2008, 06:51 PM
The operating temp should be 180 to 185. These new boats run off of the same type ecm that all newer cars and trucks have been using for years. Most sensors do not go to a closed loop data stream till the coolant temp reaches 185+. At that point the ecm controls the entire fuel air mixture, idle speed ,map sensor,maf sensor et al. Your boat speed is also registered by computer by speed sensors in tranny, hence the way moomba cruise works. Hope this helps

03-10-2008, 07:56 PM
I believe that Indmar uses a 180 thermostat in their engines. This is pretty typical. If it is operating normally, your engine temp should remain the same all of the time.

Cars/Trucks can run higher temps because they have a pressurized system. Adding pressure raised the boiling point of water. This allows cars to reduce emissions.

03-10-2008, 09:19 PM
180 is where mine runs

03-10-2008, 10:53 PM
My old boat runs at 140 with a Holley carb, a new boat running 180 would seem perfectly normal and actually like everyone else has stated this is pretty cool for an engine (unless you have a fresh water cooling system). You are going to have trouble getting it warmer, the resevoir in a boat IS the body of water you are running in (you are always pulling in a fresh supply of water less than 90F) and is not a pressurized system, a car has a closed loop limited supply system under pressure which increases the boiling point of water above 212 F or for the Canadians 100C. I would also have to say that the ECAT 340Hp engine has to run much hotter to light off the CAT but I am not sure what the normal temp for this system is!
Having had an impeller failure I can tell you that the needle doesn't read anything during a cooling system failure as there is nothing but steam in the housing and it won't read that, so IF you are always reading a temperature 140 - 190 you are GOOD and still on the cold side of what this engine was actually designed for!

PS Check out the Pride and Joy section, our new Mobius LS is at the dealer!!!! So happy to say goodbye to the Holley!!!!

03-12-2008, 07:47 PM
Yeah we were told that our's should run at about 165 but we were around the 180 mark all season as well. There was a thread last year about this and the consensous was that it does vary between 165 and 180 and that a lot of the problem is that the guages themselves are not that acurate.

Hope this helps, I know when I read that last year it made me a bit more comforatable 8)