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06 Optimax 150 Last night I was at idle speed for about 10-15 minutes and was jolted awake by one long continuous beep. Engine temp was at 170. Assuming that was an over heat alarm but not sure where the range for that would be. Put my light on the motor and it appeared to be throwing white smoke through the exhaust. After it cooled off a bit I restarted and it would heat back up and white smoke would start back after a minute or so. Thinking maybe I had it trimmed too low and exhaust was submerged. Guardian system did not restrict RPMs and it would cool down if not at idle. Went ahead and packed it in for the night and brought it home. Smoke had no odor like anything really burning. It was peeing fine as well. Thoughts?Last edited by loujoe on July 4th, 2008, 11:59 pm, edited 1 time in total.
poppit valve stuck open with trash or your water pump impellar has some damage. either will require a mechanic unless you are very handy with the wrench.
Phil is dead on as normal. It is definitely an over heat alarm and your temp should be no higher than 140 (if I remember correctly mine cycles down as the thermostats open at that temp…might be 138) but 120s is where it will operate around. Seems mine is 123 more times than not if running. You definitely dont want to be running it around that high…if you havent had an impeller changed since it was new I would go ahead and replace that while you are cleaning the poppit. Judd Lasiter
The older Opti 150s had an issue with a bypass or something to do with the water pump. It is worth having your dealer check the bulletins or calling the tech line.
if idling for long periods is a normal thing for you, you will need to get good at watching the water temp. As it gets to 140, both thermostats are supposed to open. What happens is some trash (weeds, stick, etc.) gets stuck in one of the two thermostats and it stays open. As I am sure you are aware, Optis idle with basically no water pressure. What little water that is going through the motor is going through the side with the open thermostat, the other one never opens and you get an overheat. After you take it to the shop and get it checked, watch the water temp when idling for a long period. As it gets over 140 and doesnt cool, pop it out of gear and rev it a little to get better water flow. It works like a charm. In theory, it will never get over 140 if operating correctly but getting something in the thermostats is way too routine to be running to the shop every time it happens.Bill Spence St. Albans, VT [url=mailto:billspence@yahoo.com]billspence@yahoo.com[/url] http://www.twinstatebassin.com Bass Cat Boats http://www.basscat.com Vexilar Marine Electronics http://www.vexilar.com
Thanks for the replies fellas. I believe it has always idled in the 150 range and yes I do fish a couple of lakes that often require longer idling speeds due to considerable numbers of stumps (10 mph limits) or often at night I will slow it way down just for safety when moving spots. Only has 40 hrs on it so no the impeller has not been changed. With no hot foot I cant take it out of gear and rev the engine so would that just require popping it like I would to bring up on plane? Sounds like a definite trip to the shop. Once again thanks for the info. One more question. The cap on the engine mounted oil reservoir, does it have an o-ring under the cap. While I was checking it out I took that cap off to get a good look in to make sure it was filling properly. With it being dark I could not see the oil level without getting a light in there. When I took the cap off I lost a small o-ring in the water of course. Had trouble with a check valve on that reservoir before so it was a suspect. I did not remember seeing one there before. That cap doesnt seem to want to seat well, almost like those threads are stripped a little, but my mechanic had it working fine and and filling properly after replacing a check valve last fall. Im well aware of the problems that can cause, just didnt remember an o-ring under that cap. Sorry for the long post and my limited knowledge. Learning here on the fly.Last edited by loujoe on July 6th, 2008, 12:20 am, edited 1 time in total.
I dont think theres an O ring there, but your mechanic may have put one there to get the plug to seat a little better.
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