Impeller Replacement
-
samuri33
- Commander

- Posts: 110
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- Location: Hampstead NC\Erie PA
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Impeller Replacement
Hello everyone,
I've been absent for too long from the chat, hope everyone has been well. I have a 2004 262 with a Merc. 496 MAG HO. The engine has the gen 7 raw water pump. I believe my impeller has failed, which is a whole other story I'd be happy to share if anyone is interested! I'm looking to see what folks are paying in your areas to have an impeller changed. I'd also like to get advice from anyone who has changed their own impeller on the merc 496. Looks like a bear to get to on my 262. The pump has to come out to change the impeller. I prefer to do my own work so I learn and and take pride in working on my own equipment, but this pump looks a little intimidating to get to. Thoughts?
I've been absent for too long from the chat, hope everyone has been well. I have a 2004 262 with a Merc. 496 MAG HO. The engine has the gen 7 raw water pump. I believe my impeller has failed, which is a whole other story I'd be happy to share if anyone is interested! I'm looking to see what folks are paying in your areas to have an impeller changed. I'd also like to get advice from anyone who has changed their own impeller on the merc 496. Looks like a bear to get to on my 262. The pump has to come out to change the impeller. I prefer to do my own work so I learn and and take pride in working on my own equipment, but this pump looks a little intimidating to get to. Thoughts?
2004 Cobalt 262 Merc 496 Mag HO, B3
"Mean Bean"
Hampstead NC\Erie PA
"Mean Bean"
Hampstead NC\Erie PA
Re: Impeller Replacement
They are tough and it’s important to mark your in & out hoses ( I know ). The bracket can come off with the pump and then serviced on the bench.
There are kits with metal shim plates that should you see and lines on the bottom of housing it’s important for no cavatation once put back together.
Typical shops charge 300-400 so it’s not too terrible for thier experience.
http://www.marine-496pump.com/
.
There are kits with metal shim plates that should you see and lines on the bottom of housing it’s important for no cavatation once put back together.
Typical shops charge 300-400 so it’s not too terrible for thier experience.
http://www.marine-496pump.com/
.
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2008 272 , 496 HO fo SHO
California Delta
Table Rock Lake
#FARCON
California Delta
Table Rock Lake
#FARCON
- AsLan7
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Re: Impeller Replacement
.
Yes, it's easier to just pull the engine and get to it.
. .
. .
. .
.
What a tired impeller looks like....
.
.
.
....and yes...about $3-400 depending on the shop (without engine pull option
).
.
Yes, it's easier to just pull the engine and get to it.
. .
. .
. .
.
What a tired impeller looks like....
.
.
.
....and yes...about $3-400 depending on the shop (without engine pull option
.
You do not have the required permissions to view the files attached to this post.
2002 Cobalt 262
&
2005 Cobalt 263
496 MagHO
(sold )
Erie, PA
Currently boatless (for now)
will fly for food
(CChat moderator)
&
2005 Cobalt 263
496 MagHO
(sold )
Erie, PA
Currently boatless (for now)
will fly for food
(CChat moderator)
-
samuri33
- Commander

- Posts: 110
- Joined: Thu Sep 06, 2018 8:15 am
- Location: Hampstead NC\Erie PA
- Contact:
Re: Impeller Replacement
Thank you for the website and advice. I think I might try to tackle it in the spring!cmattj wrote: Tue Dec 17, 2019 7:19 am They are tough and it’s important to mark your in & out hoses ( I know ). The bracket can come off with the pump and then serviced on the bench.
There are kits with metal shim plates that should you see and lines on the bottom of housing it’s important for no cavatation once put back together.
Typical shops charge 300-400 so it’s not too terrible for thier experience.
http://www.marine-496pump.com/
.
2004 Cobalt 262 Merc 496 Mag HO, B3
"Mean Bean"
Hampstead NC\Erie PA
"Mean Bean"
Hampstead NC\Erie PA
-
samuri33
- Commander

- Posts: 110
- Joined: Thu Sep 06, 2018 8:15 am
- Location: Hampstead NC\Erie PA
- Contact:
Re: Impeller Replacement
LOL, A7, I think I might try your way of changing the impeller, and hell, while the engine is out, change the oil and paint the bilge!AsLan7 wrote: Tue Dec 17, 2019 9:27 am .
Yes, it's easier to just pull the engine and get to it.![]()
.
1.jpg
.
.
IMG_0529.JPG
.
.
IMG_0530.JPG
.
.
What a tired impeller looks like....
.
IMG_0506.JPG
.
.
....and yes...about $3-400 depending on the shop (without engine pull option).
.
2004 Cobalt 262 Merc 496 Mag HO, B3
"Mean Bean"
Hampstead NC\Erie PA
"Mean Bean"
Hampstead NC\Erie PA
- Big Block Power
- Fleet Admiral

- Posts: 17930
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Re: Impeller Replacement
A7 is the only one I know that pulls a whinge to change oil and to change the impellersamuri33 wrote: Tue Dec 17, 2019 12:53 pmLOL, A7, I think I might try your way of changing the impeller, and hell, while the engine is out, change the oil and paint the bilge!AsLan7 wrote: Tue Dec 17, 2019 9:27 am .
Yes, it's easier to just pull the engine and get to it.![]()
.
1.jpg
.
.
IMG_0529.JPG
.
.
IMG_0530.JPG
.
.
What a tired impeller looks like....
.
IMG_0506.JPG
.
.
....and yes...about $3-400 depending on the shop (without engine pull option).
.
03Cobalt220 8.1gxi DP
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
Re: Impeller Replacement
Pulls a whinge??Big Block Power wrote: Tue Dec 17, 2019 6:27 pm
A7 is the only one I know that pulls a whinge to change oil and to change the impeller![]()
Loce it!
You do not have the required permissions to view the files attached to this post.
2008 272 , 496 HO fo SHO
California Delta
Table Rock Lake
#FARCON
California Delta
Table Rock Lake
#FARCON
- Big Block Power
- Fleet Admiral

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Re: Impeller Replacement
And here you thought I made that up. Whinge could also mean Engine.cmattj wrote: Tue Dec 17, 2019 6:54 pmPulls a whinge??Big Block Power wrote: Tue Dec 17, 2019 6:27 pm
A7 is the only one I know that pulls a whinge to change oil and to change the impeller![]()
Loce it!But I imagine he did during that time..
I give up
03Cobalt220 8.1gxi DP
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
- AsLan7
- Fleet Admiral

- Posts: 11520
- Joined: Sat Jul 29, 2017 10:58 am
- Location: Erie PA
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Re: Impeller Replacement
2002 Cobalt 262
&
2005 Cobalt 263
496 MagHO
(sold )
Erie, PA
Currently boatless (for now)
will fly for food
(CChat moderator)
&
2005 Cobalt 263
496 MagHO
(sold )
Erie, PA
Currently boatless (for now)
will fly for food
(CChat moderator)
- akorcovelos
- Vice Admiral

- Posts: 2981
- Joined: Mon Sep 10, 2018 10:07 pm
- Location: Antioch, IL
- Contact:
Re: Impeller Replacement
I’ll one up that, pull my 454 and just put a 502 with a new impeller back in!
1996 252 Whipple tuned 454 Magnum MPI, 496 exhaust, Corsa Captains Call, B3 w/Simrek drive shower.
‘Direct Deposit Too’
Antioch, IL
Fox Chain O' Lakes
‘Direct Deposit Too’
Antioch, IL
Fox Chain O' Lakes
Re: Impeller Replacement
Not sure whinge is worse....
2001 262 502 GXI (because it sounds better than an 8.2)
From the Land of the Red Man
"Black Boats Matter"
#FARCON Marine / CC Core!
From the Land of the Red Man
"Black Boats Matter"
#FARCON Marine / CC Core!
- akorcovelos
- Vice Admiral

- Posts: 2981
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Re: Impeller Replacement
You do not have the required permissions to view the files attached to this post.
1996 252 Whipple tuned 454 Magnum MPI, 496 exhaust, Corsa Captains Call, B3 w/Simrek drive shower.
‘Direct Deposit Too’
Antioch, IL
Fox Chain O' Lakes
‘Direct Deposit Too’
Antioch, IL
Fox Chain O' Lakes
-
samuri33
- Commander

- Posts: 110
- Joined: Thu Sep 06, 2018 8:15 am
- Location: Hampstead NC\Erie PA
- Contact:
Re: Impeller Replacement
Update on my Impeller explosion (see pictures)! Got the pump out and replaced the impeller. Here's what a one year old impeller likes like when your drive muffs slide down just a little and the pump doesn't get enough water for just a few minutes. Mercruiser mechanic told me that you have 30 seconds of no water before the impeller is toast! Now we're on the hunt for all the little pieces you don't see in the photos!
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2004 Cobalt 262 Merc 496 Mag HO, B3
"Mean Bean"
Hampstead NC\Erie PA
"Mean Bean"
Hampstead NC\Erie PA
- AsLan7
- Fleet Admiral

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Re: Impeller Replacement
.
Good Lord S33. That’s bad.
Thanks for the pics. Let’s get you a new one and a good flush so we can see you back on lake Erie ASAP. ( post quarantine of course
)
Who is doing the work for you?
.
Good Lord S33. That’s bad.
Thanks for the pics. Let’s get you a new one and a good flush so we can see you back on lake Erie ASAP. ( post quarantine of course
Who is doing the work for you?
.
2002 Cobalt 262
&
2005 Cobalt 263
496 MagHO
(sold )
Erie, PA
Currently boatless (for now)
will fly for food
(CChat moderator)
&
2005 Cobalt 263
496 MagHO
(sold )
Erie, PA
Currently boatless (for now)
will fly for food
(CChat moderator)
- Big Block Power
- Fleet Admiral

- Posts: 17930
- Joined: Sat May 07, 2016 8:05 pm
- Location: Neenah,Wi
- Contact:
Re: Impeller Replacement
Unreal. Did you run it on the muffs this year? That's one thing I like about Volvo is no muffs needed.
Check your pwr str cooler and T stat and cool fuel and the bottom coolers under the exhaust manifolds.
Check your pwr str cooler and T stat and cool fuel and the bottom coolers under the exhaust manifolds.
03Cobalt220 8.1gxi DP
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
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