Oceanrunner 200

[jeremyeasen]

Operating temperature seems to be a fairly hot topic, (no pun intended) but I'd like to get some feedback for my specific engine. It is a 1994 Oceanrunner 200 and my cruise is about 4800 rpms. At this speed she is about 150-160 degrees. Its a little odd, but I'll run out and it will be a constant 160, then move to another spot (same speed) after a motor shut down and this time it will be 150. It idles at 150 (home and on the water). Question is: 160 seems warm to me, and why so inconsistent? T-stats and impeller are 3 months old, but I may change stats out again to be sure. Does this seem like a problem to anyone? Overheat alarm has never gone off, but my old 92 115hp always ran at 140degrees. thanks for your imput....J

 

[Pst76]

Re: Oceanrunner 200

Just my 2 cents, but your 200 is a 6cyl and your 115 was a 4cyl. Temp difference I believe would definitely seem to be different. As far as variation in spots being that its cooled by water intake the temp of the water coming into the system could make it vary. Up here water at 37 degree's keeps motor nice and cool as opposed to mid summer at 75 degree's. Check your manual and it should give a temp running spec to refer to. I have a 150hp Ocean runner but do not have a temp gauge set up. Good luck

 

[angus63]

Re: Oceanrunner 200

Might be engine set up (cavitation at intakes), or maybe it just likes to run a little warmer than the smaller block with less firing holes. As long as you maintain ABOUT 140 at idle and less than 165 thruogh the range, I'd sleep well. For peace of mind, check your overheat horn and enjoy.<br />PS What are you measuring temp with? Dashboard gages are notorious for being out of scale, but are good for reference to indicate changes.

 

[jeremyeasen]

Re: Oceanrunner 200

angus, i am only measuring temp using the dash gauge. But as you mentioned, it was the change in temperatures that caught me off guard. It maintains the same temp for a particular run, but the next run may be a little warmer or cooler. warning horn works, and motor sits well into the water. I've never had cavitation problems turning while at high speed. thanks for the advice, and i'm not that concerned....i have Boat US

 

[seahorse5]

Re: Oceanrunner 200

The '93 and later V-6's have a completely different cooling system than OMC's other families of motors. The closed deck block is thermostat controlled at all speeds and runs warmer at upper speeds than the older V6's.<br /><br />Other style of motors use thermostatic control for low speed operation and pressure relief valves to flow more water at high speed and the motor runs cooler.<br /><br />Dash mounted temp guages are not accurate, plus the sender only measures the "skin" temp of the motor, not the actual coolant temp.