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triple_d

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I want to change my impellers. I have 1984 454's Crusaders 350hp.
can you give me instructions on where they are located ??

thanks everyone.
 
triple_d said:
I want to change my impellers. I have 1984 454's Crusaders 350hp.
can you give me instructions on where they are located ??

thanks everyone.
Click to expand...

They are located insode the raw water pump at the front right hand lower side of the engine, a small fan belt drives the the pump. I just changed mine.
 
Remove the pump, by loosening the two hex bolts mounted upside down under the pump. You need to reach them, you don't need to see them! Two hoses and the belt, and away you go. Inspect the cam for a sharp trailing edge (worn out) and the cover bushing for shaft radial play. All come with the major repair kit.
 
kimosammy said:
Why would a person not remove the four screws and the back plate to access and remove the impeller?
Click to expand...

several good reasons. Inspection of the other pump parts would be very difficult. Also, the cover holds the rear bearing to the shaft, so it will stress the system to force the cover on/off. The bearing here is graphite, brittle. Third, the bracket may make the 4 screw removal very difficult, as it has a rear plate that interferes. Sorry, for these engines, take the pump off and head for the bench.
 
My experience tells me that belt driven sea water pumps typically cause owners to defer impeller replacement and/or pump service due to the alleged difficulty of access, removal, etc. They get lazy, so to speak, and usually end up in Hot water later on!

Just a suggestion:
For those who's pumps are worn, and in need of an over-haul or replacement, consider retro-fitting a Crankshaft Pump.
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Don't let the little bugger fool you.... they work very well.
There's no side load that wears at the bearings as with the belt driven pumps.

They do require the correct space in front of the engine, but if you have enough, it's a fairly simple installation.
The impeller removal now becomes a piece of cake. Four screws... Bingo... right there.

I recently walked two gentlemen through this who made the change to the Johnson F5B-9 (both had twin engines w/ the Sherwood belt driven pumps).

The F6B-9 is larger if you need more flow capacity.
Sherwood also has a version of the Crankshaft pump if you prefer Sherwood.
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Anyway.... just a thought.
 
Sorry for what may seem like a dumb question SO: I see where the connection is to the crank but what holds the pump body in place properly ? Is that a bracket tab on the side by the hose connection? Thanks
 
knuckle47 said:
Sorry for what may seem like a dumb question SO: I see where the connection is to the crank but what holds the pump body in place properly ? Is that a bracket tab on the side by the hose connection? Thanks
Click to expand...
Not a dumb question at all!

The pump body is held in position by the shaft/bearing, and eventually the "base" unit.
The base unit bolts to the harmonic balancer via the three threaded holes for the crank pulley.
The crank pulley will offer two raised "dowels" that aligns (or phases) the base properly to the pulley, so to speak.
While we have 3 possible orientations, only 1 aligns the base correctly when the dowels are aligned.
Very easy to do!

The arm that you typically see, is an anti-torque arm.
In many cases, and if the hoses are stiff enough, the arm can be eliminated.
I am using mine minus the torque arms.
No issues to date.

Like said... no side load from belt tension as with the belt driven pumps.
Easy cover and impeller access.

IMO, this better access alone causes one to be more pro-active re; impeller inspection and/or replacement.

However, this may not work in all applications, and it does require some re-vamping of hoses.
Once done, though..... I think it's win win.
One belt that can be eliminated also (unless it also drives another unit.... which may be rare).

.
 
diver_dave said:
several good reasons. Inspection of the other pump parts would be very difficult. Also, the cover holds the rear bearing to the shaft, so it will stress the system to force the cover on/off. The bearing here is graphite, brittle. Third, the bracket may make the 4 screw removal very difficult, as it has a rear plate that interferes. Sorry, for these engines, take the pump off and head for the bench.
Click to expand...

Then it seems, the pump type is a big factor..of course. I cant recall the type raw-water seapump I have. I can remove the back cover plate by removing the four screws then pull the impeller out and replace. Replace the gasket and reinstall the four screws. I would agree I could'nt see much but I used a mirror and finger to inspect. The plate was completley flat, no bearing or hitches.
 
I believe all the middle aged Crusaders came with Sherwood E35 as stock. There are various competitive pumps; I believe there is a ITT/Jabsco that mounts the same, but different construction; two bearings forward and a flat plate cover.
 
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