Mark, While you have the impeller out, you should be able to back flush the inlet to the pump with a hose. I believe the screens are on the intakes and back flushing the intake passages should take care of the screens. What Bob said for the rest of the motor. If you back flush through the fitting with the lower unit off, it should take care of back flushing the output tube from the pump. My screens are removable. I don't know about yours. Shame on you for not having a manual by now! Watch the outlet tube and the shift linkage when you re-assemble. jim
Something tells me you could save a few bucks somewhere to cover the cost of the plugs if you really had to.... Just can't put my finger on it. Good luck with the flush and parts replacement.
Too funny.... I guess I could save some money by driving up. Wish I had, because then I could bring the boat home. Still overheating. Put in the new impeller, new water pump cover and gasket, and new plugs. Boat was fine all morning, then this afternoon started overheating again -going up into the upper 170s. It is fine at high speeds. Will run 145 degrees at WOT. But if I'm giong 15-25 MPH it will overheat. Am I ever frustrated.... I didn't back flush anything - I read those posts too late.... I guess I could pull the lower unit back off and do that... Any other ideas? I'm really frustrated guys! Thanks for all the help! Mark p.s. - Tim - I saw Joe McFarland today at Musky Country...
Mark, These thing are difficult to diagnose online, but: Please check your lower unit for water. Pull the thermostats and visually check them. You can flush out the heads and the block to some extent through the thermostat cavity. I assume your water pressure is pretty low at idle? It sounds like an obstruction or a leak at the top or bottom of the tube from the pump to the midsection. You could pull the lower and flush also. jim
I can see from the water coming out it is low. I will pull it apart again and flush everything. Any chance I put the Impeller in backwards? I don't think I did though. Where are the thermostats? Thx Jim!
The thermostats are usually at the top if the heads on the back. I doubt the installation is wrong with the possibility that there might be a leak where the water exits the pump at that seal. Or that water delivery line is kinked. Since nothing really changed, your installation is probably ok. I am concerned that the pump lower seal is blown pumping water into the lower uinit. I would like to rule that out. jim
I had just changed the lower unit oil before bringing the boat up a couple weeks ago and there was no evidence of water in the lower unit oil at that time. I'm not convinced that the water stream coming out of the pee hole is as strong and laminar as it should be - but I'm not 100% sure. From what I'm seeing online - 3.5 psi at idel doesn't sound particularly weak. The boat ran fine all morning pulling skiiers and knee boarders. Then, after a series of aborted starts while working with my niece learning to do deep water slalom starts, the motor started acting up again - climbing slowly into the upper 170s, with the alarm sounding. My boat guy in IL says that the poppets are not usually the issue on the 225's in his experience, and he was sure that a new impeller would solve the problem. I'll post pictures - you can see the old impeller had taken a "set" and was no good anymore. But, alas, I'm still having problems... If I am going about 35 MPH or more - I have no problem. Below that, it will eventually get too hot. It is hard to imagine that there is any obstruction in the cooling system but I guess the next step is to drop the lower unit again, re-inspect the impeller, and flush the system with the flush port on the back of the engine. I can inspect the thermostats and poppets if I can find them. This engine is not the simplest thing I've ever worked on... I see a heck of a lot on overheat alarm issues on optimax engines when I look on the net. Seems like a new impeller does not always solve the problem - and I'm not seeing many threads where the problem is actually resolved... So... I'm concerned. I may have to bring it to a shop - and anyone who knows me knows that I don't turn over my boat without a lot of stress.... Just don't like turning it over to someone else, I guess.
