Yamaha water pump

wlewis

Well-Known Member
Joined
Jun 19, 2008
Messages
266
Reaction score
13
Points
18
Location
Savannah, Ga
How often should a Yamaha water pump be replaced? My 250 is 13 years old, has about 175 hours on it and still has original pump. Water pressure gauge shows slightly less than half way between minimum and maximum markings, temp gauge shows right in the center between minimum and maximum. Pisser amount is steady. I’m thinking for peace of mine, replace it this off-season.
 

DennisG01

GreatGrady Captain
Joined
Sep 1, 2013
Messages
7,189
Reaction score
1,341
Points
113
Location
Allentown, PA & Friendship, ME
Model
Offshore
While top quality impellers like Yamaha, Mercury, etc can last a long, long time... they are still made of rubber and eventually rubber will fail. What you DON'T want to happen is for a piece of a vane to break off and make a clog somewhere in the water cooling passageways. At 13 years old, it is DEFINITELY a "do it" job :)

The type of water you run in has a lot to do with longevity, as well.
 
  • Like
Reactions: Sardinia306Canyon

PointedRose

Well-Known Member
Joined
Feb 11, 2021
Messages
679
Reaction score
212
Points
43
Location
San Francisco
Model
Overnighter
The other benefit to regular replacement is that the bolts for the lower unit don’t lock on. It may take some effort to get the LU off. I think Dennis bumped into this last year
 

DennisG01

GreatGrady Captain
Joined
Sep 1, 2013
Messages
7,189
Reaction score
1,341
Points
113
Location
Allentown, PA & Friendship, ME
Model
Offshore
The other benefit to regular replacement is that the bolts for the lower unit don’t lock on. It may take some effort to get the LU off. I think Dennis bumped into this last year
Excellent point! Yes, I did. I was TRYING to forget about that! ;)

Had to destroy the lower unit to get it off. In my case, the bolts were OK - it was the shaft that was seized.
 
  • Like
Reactions: PointedRose

Sardinia306Canyon

GreatGrady Captain
Joined
Oct 11, 2023
Messages
523
Reaction score
101
Points
43
Age
60
Location
Island of Sardinia
Model
Canyon 306
Yes, change this impeller immediately, impellers are cheap and much cheaper than the problems described above.

The other benefit to regular replacement is that the bolts for the lower unit don’t lock on. It may take some effort to get the LU off.
same for the driveshaft not getting stuck in the powerhead.
That was a 2016-2018 Suzuki problem on the DF300AP, but when i bought the Venture 34 with twin 2008 F250 both driveshafts where stuck in powerhead. I had both starting to get stuck but could maul them free using wedges while my buddy with the same boat and same DF300AP obviously machanic did not pulled the LU and so driveshaft got stuck so badly that he had to be cut, powerhead removed, etc, etc

I prefer pulling the lower unit every 100 hours to verify the inside, loosening and tightening the waterpump bolts, have the drive shaft disconnecting and greasing it well before assembling all again. Inspecting the inside of LU and midsection is always a good thing to do as Trust is good but control is better! We had two outboards in the shipyard with problems within 100 hours from galvanic corrosion from a 220V leaking boat nearby boat owners slip in the marina, and that can end in a total disaster if not detected asap.
When i was chartering 100 hours could happen in less than a month so i usually let fall the dive panga dry and changed oils on the beach as everybody does there in CR as other solution was paying 250$ for the forklift in Los Sueños to use a maintenance rack or put her on a trailer.

I change impellers every year and when pulling the LU in between i loosen and immediately tighten the waterpump bolts or disassemble her to verify the state of the impeller. I always use OEM impellers and never had a problem that they had quality problems within 200 hours.

Chris
 
  • Like
Reactions: PointedRose

seasick

Well-Known Member
Joined
Aug 19, 2008
Messages
9,530
Reaction score
1,420
Points
113
Location
NYC
After 13 years, I would replace the whole pump. The kit contains impeller, housing, rub plate, man gaskets and other misc parts.
After all that time, I would also suggest a pressure and vacuum test of the LU to make sure the seals are sealing.
I find that the Yami impellers last longer than some other ones like Mercs but they do age and take a set. I get 4 or 5 seasons out of a pump but usually do it due to guilt ant not necessarily need:)
 
  • Like
Reactions: loubeer

SkunkBoat

Well-Known Member
Joined
Oct 12, 2017
Messages
4,508
Reaction score
1,614
Points
113
Location
Manasquan Inlet NJ
Website
www.youtube.com
Model
Express 265
EVery three years because you need to take the LU off every three years to ensure it isnt stuck forever.
Its called "maintenance". change it because it is not broke yet.

Learn to do it. its not that hard. you own a boat.
 

drbatts

Well-Known Member
Joined
Nov 30, 2008
Messages
887
Reaction score
190
Points
43
Location
CT
Model
Express 305
I do mine every 3 years.
 

wlewis

Well-Known Member
Joined
Jun 19, 2008
Messages
266
Reaction score
13
Points
18
Location
Savannah, Ga
Well, Perhaps I'm not as dumb as I thought although my memory is lacking, I just looked through my maintenance files and see where I did replace the water pump in 2019. Still, at 5 years, time to replace it again.
 
  • Like
Reactions: PointedRose

Hookup1

GreatGrady Captain
Joined
Oct 16, 2007
Messages
3,035
Reaction score
855
Points
113
Age
70
Location
Cape May, NJ
Model
Islander
Yes - replace the complete water pump. It's a standard Yamaha replacement kit. Every 3 or so years. The impellers take a set, harden up and get brittle.

Not a bad idea to replace thermostat too. The two I had fail stuck "open" and caused a lower temp reading than the other engine.