Bravo water pump

[swampy2646]

Hello to all… It’s been a while! I have a 1991 2500 SCR I re-powered with a 5.7 MPI bravo one. Has anybody ever done this? Has anybody ever been able to change the raw water pump without pulling the engine out.

[mmwjr]

I have a carburetor 5.7 with a Bravo 2 and can pull the water pump assembly by unbolting it from the engine. Then I can disassemble it to replace the impeller.

[swampy2646]

Problem is there is no room to access the pump… I can barely touch it yet. be able to remove the bolts and hoses. There is no way of getting in front of the engine. There is about 12 inches of space between the front of the motor and the bulkhead.

[HavreDeGrace2400]

I did this today. Was dreading it, and turns out i was right to. Horrible horrible job. It took me an hour and half to take it off and again to put it back on.

My arms are bloody from the damned hose clamps all over the place. My boat has the cool fuel module with a thousand hoses blocking all access to everything. 2003 5.0 MPI. I couldn't possible remove the back half of the pump. Well, who knows. In three years when i plan to do it again i might re-evaluate.

But i opted for removing just the 7 10mm screws holding the front half of the pump to the bracket and back half with the hoses.

Buying a ratcheting 10mm wrench was the key for this. That plus extreme boat yoga skills, insane manual dexterity, tolerance for pain, cursing, cleaning out the bilge, two showers, and i got the sob screws out.

My first year on the boat, i had to know what the status of the impeller was. It turns out it was pretty good. One small tear. But three of the 6 screws were rather loose i noticed. There wasnt any leaking but hmm.

Removed the belt, one pulley.

OMG this was the worst job i've ever done on a boat. The entire thing was done by feel.



Here it is out of hte boat. Jus thte front half of the pump again...



One thing for sure... don't buy a cheap impeller. I definitely want to get three seasons out of this thing.

[swampy2646]

Uggggg….i feel your pain. I guess that method was very unconventional… But if it works, it works. what model boat was this? My 2500 was probably not offered with a bravo because of this reason, the motor sits so low and no frontal access to complete this job. last time I did it I had the motor out for a different reason so it was a piece of cake but now I’m wondering if I can do it without removing the motor.

[mmwjr]

Originally Posted by swampy2646

Uggggg….i feel your pain. I guess that method was very unconventional… But if it works, it works. what model boat was this? My 2500 was probably not offered with a bravo because of this reason, the motor sits so low and no frontal access to complete this job. last time I did it I had the motor out for a different reason so it was a piece of cake but now I’m wondering if I can do it without removing the motor.

j

In post #1 you stated that you have a Bravo one. All Bravo drives use a belt driven raw water pump that is mounted on the starboard side of the from of the engine down low. Mercruiser who makes the engines has no control over what the boat manufacturers do with design.

[swampy2646]

I stated that I re-powered with a bravo 1 and a 350 magnum mpi….original engine 5.7 alpha. What a difference!!!!

[mmwjr]

Originally Posted by swampy2646

I stated that I re-powered with a bravo 1 and a 350 magnum mpi….original engine 5.7 alpha. What a difference!!!!

True but you are asking about changing the Bravo impeller. At this point the old Alpha is irrelevant .

[swampy2646]

The point is the alpha impeller is in the outdrive, not mounted on the bottom starboard side of the bottom of the engine in which I have no access to.

[mmwjr]

Originally Posted by swampy2646

The point is the alpha impeller is in the outdrive, not mounted on the bottom starboard side of the bottom of the engine in which I have no access to.

In your case I get it but on many of boats the Bravo is preferred as the impeller can be replaced with the boat in the water. It’s also a much more robust impeller.

[shrew]

The water pump was difficult to reach on my 2800 SCR with a 496 (8.1). I used to hire small teens on the dock to remove the pump for me. My mechanic once held a 14 yr old girl upside down by her ankles to remove it.

I strongly advise talking to the parents for before approaching minors.

[swampy2646]

Hahaha…. I was thinking of that lol… Or a midget contortionist lol.(i’m sure that’s politically incorrect.)