Reoccurung water pump failures...
#1
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Joined: Sep 2008
Posts: 305
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From: Halifax, Nova Scotia
Hi folks.
My 1995 Formula 271 has a 502efi and Bravo 3.
This boat is in good shape and lives on a trailer when not in use.
I posted a while back regarding ongoing sea water pump impeller failures.
This boat has a seawater/fuel pump combo.
The consensus at the time was that the internal hose in the drive may have a restriction or be weak and collapsing from time to time and I was using the wrong muffs
I had been going thru 3-4 impellers per season., the boat being used 8-10 occasions per season.
There is no pattern for failure. Sometimes it failed running on the hose in my prelaunch start up/check over.
Sometimes it fails at initial start up in the water, after being just run ok on the hose.
I use the Mercruiser muffs that have the pin and locking tab to keep them tight on the drive.
http://www.ebay.ca/itm/Genuine-Mercu...733?rmvSB=true
The boat now has a brand new B3 drive and is still eating impellers.
I also ensure that the drive is lowered on the muffs so there is no chance for hose restriction.
Any ideas..........
My 1995 Formula 271 has a 502efi and Bravo 3.
This boat is in good shape and lives on a trailer when not in use.
I posted a while back regarding ongoing sea water pump impeller failures.
This boat has a seawater/fuel pump combo.
The consensus at the time was that the internal hose in the drive may have a restriction or be weak and collapsing from time to time and I was using the wrong muffs
I had been going thru 3-4 impellers per season., the boat being used 8-10 occasions per season.
There is no pattern for failure. Sometimes it failed running on the hose in my prelaunch start up/check over.
Sometimes it fails at initial start up in the water, after being just run ok on the hose.
I use the Mercruiser muffs that have the pin and locking tab to keep them tight on the drive.
http://www.ebay.ca/itm/Genuine-Mercu...733?rmvSB=true
The boat now has a brand new B3 drive and is still eating impellers.
I also ensure that the drive is lowered on the muffs so there is no chance for hose restriction.
Any ideas..........
Last edited by nsformula; 08-22-2016 at 06:06 PM.
#2
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Joined: Jun 2004
Posts: 1,949
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From: Omaha, Nebraska. Boat on the Mighty Mo! Longest river in the USA!
Yes, change the hose that goes from the bell housing to the transom. I found the same problem when I saw my water PSI go to zero. I bet that solves your problem😄
#3
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From: Halifax, Nova Scotia
Do you mean the internal hose in the drive.
The drive is brand, not rebuilt, I can`t imagine that hose being my current issue.
#4
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Joined: Apr 2005
Posts: 2,998
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From: Lees Summit ~ LOTO 10MM
No, the hose from the back of the water pump housing to where it connects at behind the motor. Also, see if the neck it attaches to is cracked and you're sucking air in.
The line you need is 1 1/4" dia wire reinforced hose
The line you need is 1 1/4" dia wire reinforced hose
#5
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From: Halifax, Nova Scotia
Generic hose ok, or Merc hose required.
#6
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Posts: 1,949
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From: Omaha, Nebraska. Boat on the Mighty Mo! Longest river in the USA!
There is no internal hose in the drive. You can see the hose when the outdrive is down. It's in the bell housing to the water inlet on the outside of the boat. It's molded hose and has no wire in it.
#8
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Posts: 305
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From: Halifax, Nova Scotia
As I said, the drive is new, as well as the transom.
Can`t imagine that hose being the issue at this point, but I can check it.
#9
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Joined: Sep 2008
Posts: 305
Likes: 10
From: Halifax, Nova Scotia
Coupler, steering ram, transom, gimbal, drive, props etc, All new Merc gear.
The hose from the transom to the water pump housing is likely the original, could be part of the problem
Last edited by nsformula; 08-23-2016 at 10:14 AM.




