Changing Impeller for Yamaha 150HP 2-Stroke

[RiverCat09]

I heard something about the need to change the cooling water impellor at regular intervals on outboard motors. I am fully aware that inboard/outboard outdrives need to have impellers changed with regularity, but this is the first I’ve heard about doing it with outboards.

I have a 2005 Yamaha 150 horsepower 2-stroke (model 150D) outboard, and I saw nothing in the maintenance chart about changing the impellor. What do you all know about impellors and Yamaha 2-stroke outboard motors (or the need to changes impellers with regularity on outboards in general).

Once again, thank you all for any help and advice.

[RickyF]

Same applies to outboards. I change mine about every other season or more depending on how many hours I have put on it.

[ultangler]

Here are two cents that will go against the regular advice - if it's working well and you freshwater flush your motor each and every time you use it, don't touch the impeller. I've been down this road many times and found that the impellers in regularly flushed engines will last 3 - 6 years. If the engine isn't flushed every time, 2 - 3 years is a long lifetime. If you regularly flush and the impeller has been going strong, but you replace it anyway because a year or two has passed, you run the risk of breaking something or putting in a crappy impeller - I had one for 6 years and had it replaced simply because I felt it was too old, and then had problems with the new one for several seasons. So, I always say if it ain't broke, don't fix it!

[raabman]

look on The Hull Truth - Powered by vBulletin, there are detailed step by step instructions on there under yamaha

[paxfish]

I do mine every other spring. $50 in parts and it takes about an hour.

[dwkoller]

Here are detailed instructions from my seloc manual for removing/installing the lower unit and water pump.

[RiverCat09]

Thanks for all the replies! I'm going to poke around the 'net now for a full blown mechanics manual for my Yammy

[Hunter]

Ditto Lenny's advice about how long the impeller will last if you are good with fresh water flushing. My mechanic also told me that bottom strikes and dragging your lower unit through mud/sand just once can possibly do impeller damage. So watch your electronics and trim up when necessary....Don

[27 sailfish]

Rule of thumb is about 3-4 years. Waiting 5-6 years can mean the bolts are tougher to get loose. Real saltwater - like the ocean - is tougher on the impellor then bay or freshwater. Running in silty/sandy water also tears the rubber vanes up faster.

When you flush the motor - do it trimmed about 1/2 way up. This helps flush the seal on top of the lower unit. Then trim down to drain the water.

Without a doubt - flushing EVERY trip will go a long way to prolong the entire cooling system.

[No Limits]

I agree that an impellor will last a while. How long a while is depends on how much you use your boat. Like others have said, getting sand ect in there is not a good thing. Also if you do not use your boat often or let it sit for long periods of time you can have some issue. The way I think is that it is not very hard to do or not very expensive to have done. A little $ on the up front part can save you a TON on a possible overheating issue. Just my thoughts. I know everyone has their own opinions. Good luck.