Does anyone know how difficult it is to change an impeller on a merc.225 efi 2000 model? Is there a differnce when people say water pump...or is it the same as your impeller?? Iwas told the impeller is just a small rubber wheel that circulates the water through your engine.
Thanks

Not sure about that particular engine, but the one I have done (older mariner) it was a piece of cake! Just remove a few bolts and drop the lower unit, replace the impeller and a couple of gaskets and stick her back together.

When you purchase the parts, you can request them to print off a parts breakdown, showing what part goes where.

As far as the water pump/impeller question, I'm not 100% sure, but I would say they are one in the same....

The hardest part is alining the drive shaft and shift shaft. If you have never done it before than I would take it to someone. If you live in the Dallas Mesquite area I will help you out.

Lure Buddy is correct. Getting the water tube aligned is the most crucial thing, then spline the driveshaft to the engine, then align the shift shaft. It can be really tricky for one person trying to do it.

Thank you all very much...I guess this winter I will take it down and have it fixed. Being from Wichita Falls I will probably take it to Fort Worth...Where is the best and most trustworthy place??

TOPWATER13
North Texas fiberglass has a very good repertation give him a call.

Tom H

Water Pump consists of the housing with the impeller inside - when the inside of the housing gets scored it should be replaced but ordinarily you just do the impeller. Should be an "impeller kit" available that'll include whatever gaskets shouldn't be re-used.

take it out to Larry's Marine,at Lake Wichita..Rodney can fix you up...

nice link ... very informative.

i have changed the impeller on a 150 Mariner.
it is easy.
just have 1 or 3 guys to help hold the lower unit up when you are trying to get the bolts started.
if you put the motor in gear then dont turn the prop.
take the lower unit off.
DONT TURN THE PROP!!!!!
then replace the impeller.
then DONT TURN THE PROP
and put it back on.

i forgot what it is called.
but the little tab that is right above the prop.
under the cavitation plate.
get a knife and put a small line across the tab and the cavitation plate so you will know where to lign it back up to where it was.

I have done it many times by myself. If you a small guy you might have a problem with the lower unit and getting the shaft splines to align to the power head. The problem is that you have to turn the prop while pushing on the lower unit. For me the task is best done with the motor tilted full up. I turn my prop as I push the housing down on to the impeller. It seeem to go on easier this way. I replace the housing every 5-6 years whether scored or not. I did once at 8-10 and noticed an increase in PSI. Try Gainesville for a closer location.

$27 dollar part. Not bad insurance. Did one this pas Saturday. Took about an hour. (I had a 2 year old helping with the placement of my tools)

If you take it to Larry's Marine, I would recommend getting a firm price (unless you like getting jobbed).

Those guys show to have good prices on their website, for example an impeller might be $15. When you show up to buy it in the store........it's $40.

Also, whatever you do, when they ask you if you want it "lake ready" say no. Otherwise you'll be paying for checking trailer tire pressure, maybe a new extinguisher, etc.

That's what a lack of competition sometimes results in.