Replacement of water pump in lower unit??

[jordy1380]

Ok, so one of my cousins has been talking with a boat repair specialist and he said he was told to replace the pump in the lower unit every other year?? The repair guy stated that you can often times run you're water pump a bit too much and any plastics (i.e. gaskets, O-rings, etc.) associated with that can crack so it's best to replace it every other year.

Is there any validity to this statement or does anyone have any other suggestions?? Thanks guys!!

 

[foodfisher]

Re: Replacement of water pump in lower unit??

Every year is safer, and anytime the engine is run without water. Should be a regular maintenance item. Beats an overheated engine.

 

[jordy1380]

Re: Replacement of water pump in lower unit??

So that's another regular maintenance part? Regardless of how long the boat gets used? I was thinkin that if you take your boat out maybe 2 days a week max for a few months that it would last longer.??

 

[Lightning1]

Re: Replacement of water pump in lower unit??

In my opinion, water pump service intervals are overdone.
I just keep an eye on the tell-tale, and as long as it is a good stream, I don't worry about it.
If it starts looking weak, time to replace the pump.
Never had a sudden pump failure, or a overheating problem.

 

[JB]

Re: Replacement of water pump in lower unit??

The thing about water pump impellers is to PREVENT failure, not to wait for partial failure. They don't get used up, they just get brittle. I have heard the every other year rule but I replaced mine annually. Some will last for years but others will disintegrate at the least convenient time.

Having one fail in the middle of a big lake or long trip is a miserable experience.

 

[Mi duckdown]

Re: Replacement of water pump in lower unit??

++^
Lightning1 worst advice I have ever heard.

 

[Texasmark]

Re: Replacement of water pump in lower unit??

Well I guess I sinned. I ran mine 10 years and thought it about time to change it. Pee stream was great, no OT problems. I pulled it out and everything was in great shape give a little "set" in the blades. Blades were still rubbery and pliable.

Part of this equation is usage and conditions. My usage and conditions are optimum. Therefore abuse is minimum. If I were operating in harms way like a lot of folks I would change more frequently. How frequently? Would depend upon what I found when I changed it and what I may have gotten into since the last change.

So my rule of thumb is it depends. I mean, if I were still a "tinker with it" nut and didn't mind forking over $40 to $100 a year then yeah I'd probably change it annually. But I'm not.

So this is like motor oil. Each has an opinion. Your money, your equipment, your decision.

My 2c,
Mark

 

[Frank Acampora]

Re: Replacement of water pump in lower unit??

OHO! Another "which oil to use" and "ethanol gasoline thread!" I'm going to enjoy watching this one.

That said: Do you wait until the brakes on your car fail? No, you replace them before they wear too badly and damage the rotors. Do you wait until the timing belt on a zero clearance auto engine fails? No! You replace it every 50,000 miles because if it does fail, it will cause major damage.

Since you can not regularly check a water pump impeller, conventional wisdom dictates regular replacement AS INSURANCE because overheating can be devastating to the engine. NOT will be devastating, but can be. Also, an impeller that sheds pieces can clog water passages SO, replacing a 30 dollar part whether or not it is worn makes sense. 2 years--1 year--whatever seems to make sense to you because just like butt-holes, everybody has an opinion about this.

NOW: Length of running makes very little difference in the "wear" of an impeller. The water lubricates it, but more importantly, at speeds over an idle, the impeller vanes bend back and do not contact the pump wall. At this point, the pump changes from displacement to centrifugal.

 

[Lightning1]

Re: Replacement of water pump in lower unit??

++^
Lightning1 worst advice I have ever heard.

It wasn't advice.
It was my opinion, combined with my personal experiences.

 

[82rude]

Re: Replacement of water pump in lower unit??

oh oh ,im in trouble .21 years with same impeller .1982 90 evinrude.sold it with a new one so my concience is clear.motor still running like a champ.this time with new motor will follow evinrudes advise as i have some good coin (at least to me )invested in the etec.every other motor ive owned ive made it a point of changing the impeller upon buying and if i kept it for more than a couple of years upon selling also.funny thing ,ive gone over my etec owners manual countless times and cannot find any mention of a service interval for the impeller.60hp etec 2011 if anybody else owns one and can point to a page in the manual were it says about changing the impeller please point it out for me.until then i will take the dealers advise and enjoy for 3 years then come see him.

 

[jordy1380]

Re: Replacement of water pump in lower unit??

Haha yeah I didn't think that such a simple question would turn into a battle royale of opinions!! It's basically what you feel most comfortable with when taking into consideration your engine and coinage available to replace every year. If I were to replace mine on my '88 Merc 150hp XR4 with having no boat knowledge whatsoever but I have the SELOC repair manual...how long do you think these take to replace? I'm not saying I need to replace it now, but what if I were to look at it?? Also, in regards to the water pump and starting the motor with boat ears, do you ever go above idle?? I think I have heard that you should run them a bit above idle to get the gunk out of the lines but I have read several places that when using the bellows to just run it at idle?

 

[82rude]

Re: Replacement of water pump in lower unit??

best advise i can give is follow the manf. recomended intervals for service.you can never go wrong that way.with my 90 it was strictly a lets see thing nothing else and id never tell anybody to do what i did and feel good about it.as for running on muffs, yeh dont run above idle as theres a possibility you could have a run away motor as they call it .since you have a manual it shouldnt take long to change a impeller .you proably started another war as im sure the factory manual snobs will be jumping all over you for having a seloc.:laugh:

 

[bonz_d]

Re: Replacement of water pump in lower unit??

Not going to tell anyone else what to do but I've been getting 4 seasons from mine. Though I run in mostly clear fresh lakes and don't have a problem with picking up crud from the water or the bottom. I've gotten to this point by pulling the pump and inspecting it at the beginning of the season. Then when I see a lot of set beginning or the pump housing plate isn't shinny I replace it. O ring gaskets are very cheap to replace on my smaller OMC's. Also I can pull and replace the lower unit on these in just a few hours of putzin around.

Too, just because a new one was put in each year doesn't gaurantee a pump wont fail. I've many times replaced brand new parts that were defective out-of-the-box..

 

[roscoe]

Re: Replacement of water pump in lower unit??

My dad got 20 years from his 15 hp, 10 years from his 25. Because he wouldn't let anyone tough them.
Finally after 10 years of nagging him, he let me replace them.

I change mine more often, every 2-3 years. I have water pressure gauges on my big motors, and keep an eye on my telltales.

The rubber can get chewed up pretty quickly if not kept in the water.
Same for running through sand bars.