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Random Quote: Any Boat can be a Minesweeper--ONCE !
I took my boat for the annual maintenance check. The guy at the dealership/service dept asked me if I have had the water pump impeller replaced within the last yr or so. This is a 2003 ox66 yamaha fuel injected VMAX 200 hp engine. I told him that I had had no problems and had not replaced anything since purchasing the boat 1 yr ago from a dealer.
Sooooo, this guy really wanted to replace the impeller, without my complaining about a waterpump problem, and without even seeing the engine. He told me that "all" engines should have the impeller replaced every two yrs or so. He also said, that if nothing else, the lower unit bolts should be removed and lubricated or they might seize/lock, and you wouldnt be able to get them loose when the time came.
Is this guy trying to scam me? I dont doubt that the bolts might lock if not lubed...........but cant you just take one out at a time and lube it, then tighten it back up without breaking the lower unit seal? I'm usually of the "dont fix it unless it's broken" school of thought. I think I'll wait til it breaks.......if it ever does. Any thoughts?
2) Replace your impeller after each time you run the engine
From what I could determine, every other year is reasonable if only because the rubber gets brittle. I am going to do mine this year.
With all of that said my 1999 Honda 90HP is running on the original impeller and cooling quite nicely I might add. I won't push my luck though...6 years seems more than a reasonable life for that part.
Impellers loss there flex,and don't put out the water that is needed.Change out every two years is a must.Get a shop manual and save about $75 to $100 in labor,its not that hard of a job!
we do them ever 2 yrs regardless the rubber takes a set and loses water pressure . if you wait till it breaks its going to be when you are out alone at night with a storm coming. yamaha bolts seem to corrode faster than others for sure.
I just did mine on a year old motor (125hrs) and it needed it. I run shallow a lot and , although the impellor looked OK, the housing was scored more than I expected. All that sand and mud doesn't lubricate very well. I had noticed that the water pressure was down a little and it took longer for it to start spraying water after starting. Now the pressure is what it was when new.
Regards,
__________________ Capt. Barry
'04 Donzi 23ZF w/ '08 Verado 300
'04 John Sport 15 w/ '03 Johnson 90
That service deptarment's recommendation is reasonable.
An impeller change is something you do BEFORE there is a problem. It is a critical component (that is made of rubber) and wears. Just to put it into perspective, I have seen manufacturers (my old MerCruiser comes to mind) recommend an impeller change every 100 hours. When I buy a used boat motor, the first thing I do after the purchase is change the impeller. That way I KNOW when the last time it was done.
Actually, it's such a routine preventative maintenance (and so easy to do) it's something you would want to be able to do yourself. Get yourself a service manual for that motor. Just for kicks, ask that service department if they could teach you how to change the impeller when they're changing yours. You might be surprised. There's a local (to me) service department that on a couple of occasions, has let me use their shop, tools, and even things like grease and sealants, so I could do the work myself because they're so swamped with a backlog of service.
__________________ Grady White SeaFarer 226 w/Yamaha F225 - SOLD
If you run your boat a lot in shallow sand bars, etc. you may even need to replace the impellers every year. The sand acts like sand paper on the rubber blades. If not, every two years under normal use should be fine. More than two years and you're asking for trouble. You may be stranded out there at the worst time or you may overheat your engines, a big NO!
After 3 seasons my 50hp is still pumping strong. It only gets 50-75 hrs per year & seldom gets a shot of sand through it. Also, the engine is not winterized for it's 4 month layup. It is given a startup every couple of weeks to give everything some movement. Never changed an OB impeller myself. Done my diesel. It is not rocket science. When it starts to show signs of getting weak I figure I can always do the job on a beach. The boat is inwater kept in season.
Hey, if the engine is pumping well & you are in the habit of keeping an eye on it at every startup, go for another season especially if you are prepared to do the job yourself & the boat is trailer kept.
I change the entire water pump every 2 to 3 years. I run in shallow water and sand will grind itself into the metal that the impellar sits on wearing it out even faster. It isn't that much more expensive to change the whole unit.
Generally, the engine's manual will have a "maintenance schedule". This will list what is to be checked or replaced and how often. The impeller is a part that wears with use and is usually changed every year or two. Sometimes they fail by breaking up in small pieces that then find their way into the cooling passages. This is not good. Better to change it as recommended.
"gibbsb" has it right. Get a pressure guage, when the pressure drops, change the impeller. I pulled one out 3 years old, like new, no pressure drop. Motors run in sand might need more maintaince.
All impellers should be replaced every 2 years regardless of use. I am a former engine mechanic and his reccomendation is sound. First of all, there is no seal on the lower unit. The line between the upper housing and the lower unit allows water to flow through it although it does not appear so to the normal person. Secondly, the suggestions to take the bolts out and put antiseize on them is right on the money. If you don't and you use it in salt water, you will surely have to burn them out someday and this will ruin the paint on the lower unit as well as up the labor charge for the changeout. This guy is a mechanic you want to stick with because he is doing you a favor.....pay now or pay more later like the old Fram Oil commericial.
The last point is the most important. If you leave an impeller in too long, the fins can break off in pieces and stop up the water flow in the powerhead and possibly cause a complete powerhead failure. You see, the impeller fins are rubber and they are seated in a metal housing and are bent to pick up water as they turn. No need to tell you what a powerhead cost as you probably know. I have seen all of this happen over the years and it could have all been avoided by doing the water pump changeout every 2 years no matter what.
atlanticbeach - 2/14/2006 10:06 PM Secondly, the suggestions to take the bolts out and put antiseize on them is right on the money. If you don't and you use it in salt water, you will surely have to burn them out someday and this will ruin the paint on the lower unit as well as up the labor charge for the changeout. This guy is a mechanic you want to stick with because he is doing you a favor.....pay now or pay more later like the old Fram Oil commericial.
Hope this helps.
very true.......i learned the hard way and mine went only a year and a half and one of the studs seized into place, what a pain!
? water pump impeller? 
