Looking for some insight about engine temps

[Ryan1135]

Hey all, I have a 2007 XLV GG edition. It has the indmar 340 assault. I've been running the boat most of this summer without much trouble, but I'm concerned about my engine temp. My gauge seems to cycle to 180 and then my thermostat opens and i come down to about 160-165. the gauge is pretty vague and has only a few temp lines on it. One time earlier this year I ran into limp mode while pulling a buddy wakeboarding. wouldn't go over 2k rpm and was running over 180. So i replaced the thermostat and impeller, still does the same 180-160 cycle. I did buy the Bakes Indmar cooling line replacement that reroutes the cooling system to a "better" route for CAT engine temps. I Just dont know if i need to install it, as ive read from a few people on the malibu and mastercraft forums that it did not do anything better. Can any let me know if my current temps are normal, or if i should be concerned? And does anyone suggest that i put the new cooling line system in?


Thanks,

Ryan

[Schneider]

I am having a very similar experience with my 2002 mobius LSV. Just replaced the impeller, fuel pump, plugs, wires and d-cap.
Despite all that, still experiencing an abrupt loss of power at high RPM. I did read hear that the ECM (Indmar computer) will shut you down if coolant fluids get to a certain level? I have not yet replaced my thermostat.
Did you ever resolve??

[Ryan1135]

I am having a very similar experience with my 2002 mobius LSV. Just replaced the impeller, fuel pump, plugs, wires and d-cap.
Despite all that, still experiencing an abrupt loss of power at high RPM. I did read hear that the ECM (Indmar computer) will shut you down if coolant fluids get to a certain level? I have not yet replaced my thermostat.
Did you ever resolve??

I have not yet been able to get the temp to stay stable. I recently contacted Indmar asking if its a normal to see a swing in temps while operating but have not had them reply yet.

[bergermaister]

Thermostat is a cheap/easy replacement. Don't go through a marine dealer though! Go to your local auto parts store, say you need a high flow 160 thermostat for a small block chevy. Should be about $25.

I had some issues with fluctuating and climbing temps - replaced the thermostat and never a problem again. I keep a closer eye on it now when we are pulling with a heavy load of ballast.

What kind of high RPM are you talking about? At WOT I hit a rev limiter around 4750-5000rpm. I think it's got more left in it but I'm sure that's the safety margin built in.

[Schneider]

Thanks Ryan and Bergermaister!
Ryan....have you experienced "limp-mode" since you replaced your t-stat?

[Schneider]

I have replace the impeller, the thermostat, oil, oil filter, plugs, wires, d-cap and fuel filter. I have inspected the transmission cooler and there is no blockage.
I am stumped and looking for ideas. Was considering changing the temp sensor?? Running out of options. Still overheating and boat goes into LIMP mode. Anyone have any good ideas.