Yamaha 250 water pump maintenance

[Tom Wadsworth]

I have twin 1991 Yamaha 250's and need to change the water pump impellers. It would help to know a few things first.<br />About how much does the foot itself weigh?<br />How much clearance is needed before the foot can be pulled away from the engine? My boat is on a cradle and there is about 1" clearance between the skeg and the ground. Can the foot be pulled with the motor tilted?<br />Any special things to do, not do, or watch out for?<br />Is there a factory trained Yahama mechanic in the Philadelphia area? I live about 40 miles north of Philadelphia and need a Yamaha mechanic who will work on a 250. I do not have a trailer but can probably get the boat running well enough to take it to a shop on the Delaware River.<br />Thanks <br />Tom Wadsworth

 

[rbu]

Re: Yamaha 250 water pump maintenance

I'm not exactly sure how much the lower unit weighs but one person can handle the job alone. I'll take a guess at 50-60 lbs.<br /><br />Yes, you can pull it off with the motor tilted. The drive shaft is pretty long so give yourself some room.<br /><br />Special things to do, not do ... DON'T SNAP OFF ANY OF THE BOLTS HOLDING UP THE LOWER UNIT! Believe me, it sucks to do that. Remember, there is one bolt under the trim tab zinc. You'll also want to remove the speedo water pickup hose. Actually, you should get a repair manual, it will give you all the directions you need. I have a Seloc manual and it is pretty good.<br /><br />Not sure of any Yamaha guys near Philly. I live outside Trenton, the marina there specializes in performance boats not outboards. I keep my boat down the shore for the season, there are plenty of guys around there but without a trailer, that's not an option for you. Check Yamaha's website, they list all dealers/service shops.

 

[Tom Wadsworth]

Re: Yamaha 250 water pump maintenance

Many thanks <br />Just what I need to know<br />Sounds like about an hour's job if the bolts come out ok.<br />TW

 

[Tom Wadsworth]

Re: Yamaha 250 water pump maintenance

Re: Water Pumps<br />Have Managed to pull the foot on both motors<br />After pulling the water pump cover there is a "cap" of sorts that holds the impeller. The Yamaha manual shows about 4 small 'washers' here.<br />Does this cap snap off, screw off or other?<br />Do not want to tear it up if not necessary.<br />Used heat, penetrating oil etc. but still wrung off two bolts (foot not off in 12 years).<br />Any possibility / experience with using stainless steel bolts in the foot<br />Thanks<br />TW

 

[rbu]

Re: Yamaha 250 water pump maintenance

There should be 4 bolts that hold the waterpump housing on. There are also 4 washers on those bolts, I believe that they are flat on on end. Is this what you are referring to?<br /><br />There is a stainless 'cup' that fits in the housing, this is what the impellor spins in. You'll notice that the hole for the shaft is not centered. This is how the impellor blades get pushed together and squeeze the water up.<br /><br />Did you snap the heads off the bolts?