Any tips or tricks for R & R water pump 7.4 ?

[sprink56]

My starboard raw water pump is leaking so bad that I have got to replace it. It is going to be such a biatch to get to that I am not even going to consider a "kit". Mine is an express so the engines are cramed up against the bulk head at the front of the bilge.

As always a bit of prep will make this easier. I have already cleaned the bilge and sprayed some penetrating oil on all of the bolts. Any ti[ps and tricks from my Sea Ray brothers are welcomed.

My engines call for the Johnson F6B series...any other more economical suggestions are also welcomed....these pumps run about $225 ea out the door.:huh:

 

[rondds]

Sprink
If you had the original engines I'd be real capable of talking you through the process. But it sounds like your pumps are different and you have that LH and RH engine setup. Since both my engines are LH (we've had this discussion) both my pumps are on the RIGHT side of each engine.

As for access, all I can say is that you literally have to bend at the waist, lay your lower half on top of the engine and get your torso into the space btwn the bulkhead and the front of the engine. I pulled the hoses off first, then the belts (I have v-belts, not a serpentine belt), then the brackets and then pulled the entire pump out. It's good to have someone to hand you the necessary tools. To loosen the hose clamps it's easier to use a socket either on a rachet or a screwdriver type socket holder. Regular head screwdrivers slip off the clamp screw too easily and before you know it your swearin' like a pirate and sweatin' like a racehorse.

 

[carterchapman]

...and before you know it your swearin' like a pirate and sweatin' like a racehorse.

Been there, done that. Great words Doctor!

 

[sprink56]

My pumps are mounted on the center of the engines. The support brackets are both on the right sides of the engine,therefore the port side will be easier to change than the starboard side. I can't get between the cockpit floor/seat pedestal and the engine...I have to work from the center between the engines. I think that if I remove the alternator and the over flow bottle I might have a shot at it.

Are the mercruiser engines set up with a belt driven pump or is it mounted to the crank pully? BTW I have twin belts.

The kid down the street has done a few Sun Dancers and said about $120 labor for him to do it...sounds tempting.

I can by the pump for under $200.

 

[rondds]

Mine has a short belt that runs to the main pulley. This belt is too short to be able to maneuver the pump out and it attached to the main pulley on top of the alternator belt. When I did this job I also replaced all the belts (since I had to take them all off anyway). But my dumbass forgot to replace the alternator belt, which I only realized AFTER reassembling EVERYTHING. SO, many expletives later, I got back into my Grandpa Al Lewis position to take it all apart again in order to replace the alternator belt. After that exercise in futility, I had gotten pretty good at the game.

For me it's the thrill of the fight, BUT $120 is very tempting. The first time I paid almost $400 for this job and I supplied the parts! So I will be doing it again the next time!

 

[fwebster]

Write the check.............you'll spend almost that much on docs, drugs and Advil to get over doing it yourself.

 

[sprink56]

Any one know what the "book" estimated hours are for this job?:huh: I'm guessing 2~2.5 for a trained marine tech with the right tools.

 

[wileecoyote]

Do you have any pics? From the previous ER pics you showed it seems like you should be able to climb right in there. Are you talking about the rubber impeller pump, or the circulator pump on the front of the engine. I'm thinking you mean rubber impeller, but you said it's in the center of the engine, so made me wonder. I think the only person I could hire would be a 50 lb midget! They would be the only person that could fit down there.:smt021 This is my favorite smiley, reminds me of my time on the boat so far!:smt021:smt043

 

[Don Sr]

I just did mine on my 90 270DA 7.4L it would be easy the third time as it took 2 attempts to get it right, LOL. I mistakenly hooked the sea water hose to the wrong side of the pump. Went to drop the boat in the water on a very busy day and found out the engine high temp alarm works. :smt021 Had to pull the boat back out and ask the marina what i did wrong - they said to make sure and check the direction of rotation of the belt as the suction and discharge ports vary with rotation AND make sure the sea water hose is connected to the inlet - the sea water hose is the hard hose. 5 hours of a lot of sweat -

 

[sprink56]

Do you have any pics? From the previous ER pics you showed it seems like you should be able to climb right in there. Are you talking about the rubber impeller pump, or the circulator pump on the front of the engine. I'm thinking you mean rubber impeller, but you said it's in the center of the engine, so made me wonder. I think the only person I could hire would be a 50 lb midget! They would be the only person that could fit down there.:smt021 This is my favorite smiley, reminds me of my time on the boat so far!:smt021:smt043

It's the raw water pump that mounts directly to the crankshaft pulley. There are 3: bolts that hold the flange of the pump to the pulley. In my research I have discovered that MPI, Crusader and Volvo use this set up as well as a few of the deisels. I think Mercruiser uses an off set pump with a belt driven arrangement.

This is a picture of the Volvo arrangement. Mine on the MPI is similar.

 

[sprink56]

Here is the result of the raw water pump/alternator swap.

At 10 AM UPS arrived with package. By 11 AM we were at the boat opening hatches and closing sea cocks. By noon the water pump had been removed and replaced with all hoses in place. At 12:15 t new alternator was in place and we were splicing wires and setting up new connections. The swap from 55 amp up to 95 amp was fairly seamless untill we ran into mounting bolt differences and had to modify with temporary thru bolts and washers untill I find the correct blt for the tension adjustment. Total ET...1:45.

It helped having a 19 year old turning the wrenches and the old man (me) directing and fetching.

I paid my helper $120 for a job well done.:thumbsup:

Boat runs great...I stiil want to replace the starboard side belts and install the correct bolts.

The only down side to this deal is that when I got to the boat the aft A/C had quit working...but thats another thread.

Break Out Another Thousand:smt013

 

[rondds]

Good deal Sprink! I'm sure the second one will go even quicker. Now I have to go find your AC thread!