Possable water pump or impellar going bad?

saltfisher

Petty Officer 2nd Class
Joined
Aug 22, 2007
Messages
111
1988 150 black max. On idle the water trickles/runs out of the "pee-hole" at a steady pace. When givin throttle then it comes out in a steady stream. Could the impellar be bad? or maybe the water pump be going bad? Or is this normal? How much would each be installed if i decide to do it to be on the safe side (on average). Water pump was never replaced, also i dont think this guy never replaced the impellar either because he said he only used the boat once per year and water always came out the hole. Im doing the impellar no matter what as thats normal 2 year maintance.

thanks
 

Laddies

Banned
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Sep 10, 2004
Messages
12,218
Re: Possable water pump or impellar going bad?

When the water trickles till you speed the engine up it's usually the impeller has a set
 

saltfisher

Petty Officer 2nd Class
Joined
Aug 22, 2007
Messages
111
Re: Possable water pump or impellar going bad?

How much should I expect to pay for one and install?
 

j442w30

Petty Officer 1st Class
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Jan 9, 2007
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264
Re: Possable water pump or impellar going bad?

The impeller usually costs between $5-10, maybe more and figure a 1/2 to 1 hour of labor to drop the lower unit and swap them out. Those are just rough estimates but for half the price you could pick up a Mercury OEM service manual for your engine and an impeller, do it yourself, and never have to pay to have it changed again.
 

saltfisher

Petty Officer 2nd Class
Joined
Aug 22, 2007
Messages
111
Re: Possable water pump or impellar going bad?

The boat comes with a service manual for the motor. So i guess im good to go. I work on cars, and did that for my job for 3 years, have my inspection/emission license, so it shouldnt be a big deal.
 

Robj

Lieutenant
Joined
Mar 22, 2007
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1,441
Re: Possable water pump or impellar going bad?

I have never bought an impeller for $5 to 10. More like $30 to 40, maybe even more for your motor. Count on about 1 to 2 hours to install, especially if you have never done one. I would buy a Merc as opposed to an aftermarket, never had good luck with aftermarket. I find for impellers OEM is better. That is my $0.02.

Have a great day,

Rob.
 

rblanc9000

Cadet
Joined
Aug 22, 2007
Messages
21
Re: Possable water pump or impellar going bad?

I had some concerns with my 225 Black Max , It just pee'd when at ilde and after running hard and stoping it steemed and sprayed water out the pee hole. I went to The Mercury dealer and got both the upper and lower water pump kits for about $85 which includes all the housings the impeller the lower seal for the bottom end and all the gaskets and plates. Putting the pump in is fairly basic and if you have a manual your all set. It took longer to find all the bolts than to get it off. Mine had three up front two on the sides under the side fins and one in the very back under the fin to counter engine torque. You can get the fin off by using a socket and a 6inch extension from the top of the lower unit. It took about 45 min to get it off a hour to replace the pump and about a hour to put it together { had some trouble lining up the shift shaft}. Took it out and it sprays a steady stream all the time and no more steam when I stop. My local mercury God suggested to put RTV sealent between the back section (exaust)and the water pump section to make shure no exaust leaks in on the water pump housing If you have any suspicions about how good its working put a new one in, consider how much it will cost to repair upper end damage if it overheats to much, from one auto mechanic to another.
 

tmcalavy

Rear Admiral
Joined
Aug 29, 2001
Messages
4,005
Re: Possable water pump or impellar going bad?

You should be able to do the impeller/pump change if you have some wrench skills. This maintenance should be done at least every other year if not every year at the start of the season...and of course whenever you suspect or see a drop off in water exiting the telltale hole. That said, I'll also note this...my old 73 Merc 500 inline 4 wouldn't pee a good stream at idle (700-800 rpms). It would put out a stream, but weaker than when running wide open (up near 5200 rpms). Used to bother me until I discovered that it was running cool enough at idle even with the reduced stream...learned this by placing my hand on the water jackets while it was running. If it's too hot to touch and hold onto at the water jackets while running, it ain't getting enough water flow and it's time for service.
 
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