Reoccurung water pump failures...
 

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..........

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😄

¸

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.

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

That`s easy enough.
Generic hose ok, or Merc hose required.

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.

If you did not replace the Transom Assembly then you did not replace the hose in question.


The hose in Transom Assy. is P/N 32-8M0090859

That`s the hose I thought you meant, I just mis-descibed it in my reply.
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.

Everything is new from the flywheel.
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

Yes, replace the hose from the inner transom assembly to the sea pump, they can collapse internally just like a radiator hose

Edit: make sure you don't have them reversed.