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loujoe.
A week or 2 ago I posted about an overheat alarm which occurred while I was idling for an extended period one night. The responses ran down the impeller, poppet valve and thermostats. 06 Opti 150. After having the impeller replaced I thought the problem was solved plus I had water pressure (#20) at wot that I never had before. Previous about #14. Temperature would hit about 147 and then taper off at idle. Friday night back out after dark and now it still wants to overheat at 2-3 mph. 5-6 mph produces enough water pressure to keep it cool. Normal fishing probably would never reveal this issue and its not a problem to just not idle that low but it seems wrong that I cant. Any additional thoughts?
Did you check poppet valve. I had same problem once with overheating while idling, but temp was fine if I had some speed. Found the poppet valve was stuck open and causing the problem. Since we fixed that, Ive never had an overheating problem again. Just a thought. KentKent Charles 2002 Pantera Classic & 200 Yamaha VMax
Im no expert by any means but I can share whats happened to me in the past. I have a similar situation going on with my 225 Pro XS from time to time. If I idle a lot to look at structure or through a long no wake zone and then kill the motor but then crank it back in a matter of minutes my Smart craft gauges will go up to 170 plus. It only stays there for a bit until the water gets back and then it cols down. It never overheats under any other circumstances. I called the dealer and I was assured that this happens quite a bit. I dont get the alarm while idling. Only if I cut it off after idling a ways and then starting it back quickly. Normally my motor heats up to about 130 or 132 and the thermostats open and it comes back down to about 120. I did have the opposite happen to me one time where a piece of trash got caught in the thermostats and they were stuck open. Couldnt get the motor above 90 degrees. Ive been told this could be worse than overheating on an Optimax. On the other hand Id never have known it was happeing a few years ago without the Smartcraft gauges. All of this may not mean anything of course in your particular situation but it does sound similar. Id appreciate it if someone disagrees and can tell me what I should be looking for as well. Thanks
Something is up and there is no comparing experiences between 150 and 225. We think with the heat finicky divider plate and tuner that we would have a dealership check it out better. There was a bulletin on pump housings on older 150 Opti engines. Though we think those were 2005 model year. Perhaps it was 2006 and our memory is rusty. Still get it straightened out or the excess heat will be troublesome.
BasscatRJ, I read somewhere just recently that your situation is indeed common and the restart would produce “false” overheat alarms. The recommenedation was to NOT start your motor and then fiddle with your boat before take off. When you shut it off the water settles and the engine heats up so on re-start there you go, overheated. I only know what I read but it sounds like yours is behaving normally if put in the right situation.DPT2005 – Can you describe where I find the poppet valve? I guess another trip to the local Merc dealer is in order. I need to order the manual on this opti so I can become more familiar with this engine. My BassCat dealer is 3.5 hours away and that is not cheap with todays gas prices. Thanks BC and everyone else for being so helpful.
I am not familiar with your particular motor. I have a 2002 Yamaha 200. I had my local dealer fix my problem as I am not the most mechanically inclined. He explained the poppet valve situation, and it was an easy fix. I would also suggest a trip to your local mercury mechanic. That doesnt have to be a BCB dealer. Do you have a closer mercury mechanic. Good luck. KentKent Charles 2002 Pantera Classic & 200 Yamaha VMax
DPT2005 Sure do have a closer merc mechanic. They swapped out the impeller last time. Like you Im not inclined to get in there and start jacking around with it. I have more confidence in BCB dealer but that will have to wait until after the fall season.
loujoe, First contact the dealership you have that did your work, and let them know you wanted it as a matter of record and have their input as well, thus you are going to contact CS at Mercury for documenting this one. Make a call to the Mercury Customer Service desk looking for options and bulletins. Explain to them that you are circumventing the knowledge curve because your local Merc. dealer installed an impeller last time and that did not rectify it. Ask about any outstanding service bulletins on this series, and see if they could contact the local Service Manager with those, or their thoughts. Be nice about it and not disgruntled and they usually cooperate pretty well. Especially if you are trying to work through one of the service centers. It also will help your local service center to more inquisitive on their discovery with the engine. Handle this properly and you should find some satisfaction and confidence in the end. Folsk get a bit defensive when you hammer an issue home. Though if there is resistance, just take it slow and reiterate you are looking for resolution not confrontation. From your post above we thin you can handle this properly and when it all washes out you should gain the result you desire. If any of the above fails or breaks down, then contact the manager or owner of the original BCB dealer and gain their intervention and they should be able to involve their local Tech Rep from Mercury. Processes, processes! BCBLast edited by Bass Cat Boats on August 7th, 2008, 1:33 pm, edited 1 time in total.
Thanks BCB. Ill be gentle. E-mailed Sherm today and we will get it straighened out. In the meantime since the “other” dealer is closer I will handle it with them as you have advised. Cant say enough how great it is to have you guys to turn to.
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