Merc Water Pump Impeller Replacement Question

Carl

Carl

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Staff member
I need to replace my impeller on my 2003 Merc 25hp. I've watched a few You-Tube vidoes and am thrilled to find out I have to remove the pull started & a small screw to get to the shift linkage. Oh Boy.

Regardless, for those of y'all who have done this, do you recommend I get the kit with the new housing, seals, etc.., or just grab a new impeller???
 
Maybe get the whole kit (with housing), and see how it looks after you disassemble. It's better to be prepared and have the parts ready to replace.
In my experience, the housings last longer than the impellers, since impellers should be replaced BEFORE any significant wear/tear. But, I have to admit that I usually wind up replacing the housing at the same time, as I rarely take chances with boats.
 
Carl,
To replace or not to replace... Depends on how much sand gets sucked into the pump and for how long it's been since it was new. I've had housings that really needed replacement and others that looked virtually new. If it's the original 2003 housing I'd get a new one. Having the motor apart during duck season isn't the time to have to stop and try and find a part.

Best!
Scott
 
Especially with the holiday season coming up. Get all the parts you may need Dealers in the NE seem to close down between Christmas and NY.

I also remember getting some grease with the kit or they recommended it w the install.

Phil
 
Looks like the parts place can have one by 10:00 am tomorrow morning for me.
Guess I know what I will be doing Saturday morning while my boy takes the ACT.
Any advice on doing this?
Other than don't loose the bolts and screws!
 
Make sure a decking screw doesn't fall into the water pump. Just ask Bill Burruss!

Seriously, like Scott said, sand is the enemy of the housing.
 
Any advice on doing this?
Other than don't loose the bolts and screws!
Click to expand...



Carl,
You forgot to ask "what do I do with the extra screws I ended up with after everything is back together?" (don't want any "extras" either)
Just keep you work area clean and organized and you will be fine. Pay attention to screw length, sometimes the bolts holding the same piece are not always the same length in every location.
 
Carl boats.net has scematics and part #'s so you can see how it goes together. I'm pretty sure you can buy the whole kit from them too

Here is my tip: if it has seen a lot of salt be ginger with the bolts they are a bitch to drill out if you snap them off. I had to do that with my 76' 25 horse evirude, not fun.
 
All good advice, make sure you don't start the motor with the impeller dry because it will tear the little arms right off. I have seen that way too many times and used to keep a victim impeller right on my desk to prove it to non believing students. Short answer- replace it all and keep the usable parts in a coffee can for later emergencies (you should see my garage) ;-)))
 
Carl

One other thought. Since you run in salt and brackish water when you reassemble you may want to put a little anti-sieze on the bolt threads. It is a silvery paste that really helps future disassembly. Any auto store will carry it. I routinely put it on trailer lugs and other threaded hardware subjected to water submersion. You might find some specifically for marine applications.

Eric
 
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All good advice, make sure you don't start the motor with the impeller dry because it will tear the little arms right off. I have seen that way too many times and used to keep a victim impeller right on my desk to prove it to non believing students. Short answer- replace it all and keep the usable parts in a coffee can for later emergencies (you should see my garage) ;-)))
Click to expand...

Seriously. You should see his garage. He has enough parts to build an omc Frankenstein motor for every boat on duckboats.net
 
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