Pontoon Boat & Deck Boat Forum

Any opinions on when I should change my impeller? I have a built in 2008 yamaha F150 bought new in 2010 and am going on my 4th season with the original impellar. I run in a farley deep clean lake, but do beach my boat so it gets some mud and sand exposure when pulling off the beach.

I had a 150 06 had it 6 years ran it. Every weekend and never changed mine and never had a problem. I know guys who have it changed every season when it is serviced and other who change it when there is a problem. I have been told as long as the water flows good through pee hole no problem.

I think as long as your pee stream is *strong* you have nothing to worry about. As the impeller wears it will grow weaker and weaker, and of course your cooling won't be as efficient. My pee stream shoots out almost straight and has some definite force to it. I think when it starts to "arch" I would use that as a warning and replace it proactively. I'm sure that some have catastrophic failures, but by keeping track of it this should alert you way before time that a new one is needed.

When I rebuilt my impeller I put a "bug" (a mark with a fine tip permanent black magic marker) on my water pressure gauge to notate the pressure at hot idle when new. It's a convenient way for me to check the impeller's performance - or lack thereof - before every departure since it's difficult for me to get to the back of my boat for a quick visual check. It's always still a good idea to eyeball it as well since I never trust gauges 100%.

1roadking wrote:Any opinions on when I should change my impeller? I have a built in 2008 yamaha F150 bought new in 2010 and am going on my 4th season with the original impellar. I run in a farley deep clean lake, but do beach my boat so it gets some mud and sand exposure when pulling off the beach.

This is another one of those subjects that get's debated quite a bit. I have a Yamaha 75 four stroke. The manual says the water pump should be changed out every 200 hours or once a year... Most of the guys I've talked to said do it every 2 years.... Just today I picked up my boat from the man that service my outboard.. one of the things he did was change the water pump... The motor is 3 years old so he felt it should be done... his advice to me was if you run in area's where you get a lot of mud or sand, you should change it every 1 to 2 years ( depending on the severity of the grit and dirt your motor is subject to )... if not, then he recommends every 3 years... I've got friends who havent changed the water pump in 7 or 8 years and so far...( knock on wood ) no problems.... me, I think I'll stick with every 3 years... cheap insurance.

I'm not sure what the optimum frequency is, but if you wait too long, the impeller tends to get brittle, and if it starts breaking apart you'll have bits of impeller material throughout the cooling system...not fun to clean out.

Our impeller was done at 5 years and looked good. I don't run in muddy/sandy water so I think that helps.

The buy who does my PM on the boat and motor said that the Yamaha impeller is much better than those found on other motors. I had right at 100 hours on the motor and he said it should be no problem to wait until the end of next boating season to change it out and it might still be good.
LOTO gets lots of sand and mud suspended in it in the spring and sometimes in the summer if we get heavy rains. In six years on my Optimax on the bass boat, I've only had it changed once, but then I don't put a lot of hours on the motor. It has about 150 hours on it (2006), but if the trolling motor and an hour meter on it, it would probably read over a 1,000. A lot of times, I'll just back out of the slip, turn off the Opti and troll for a couple of hours and then use the big motor to come back to the dock.