4-53 Raw Water Pump

[cb48lrc]

I have a small leak at the raw water pump, coming from the shaft end. I have a new pump to replace it with the question is.
Can I just remove the pump by taking out the three bolts that are attached to a larger plate or do I have to remove the plate. The pump is a Jabsco 17050-0001 with a spline billet on the input shaft.

 

[DCMY #92]

I have 6V53s but I expect the accessory drive is the same. You can remove the pump at either place. It's been so long since I replaced a shaft seal I don't recall if that can be done with the pump still mounted to the accessory drive cover plate. You will need the correct gasket for whichever joint you break. If you remove the accessory drive plate (larger flange) you will also need a new copper washer for the bottom bolt. This copper washer is an oil seal. If you don't have a new one you can sometimes get by by heating the old one red hot with a propane torch and letting it air-cool to anneal it. Take the washer off of the bolt before heating it.

There is a floating gear coupling between the pump shaft and the drive sprocket. It will usually come out with the pump, fall off, and disappear to who-knows-where. So, try to keep the pump tilted drive-end up as you remove it. If you remove the pump at the small flange I don't recall if this coupling will remain captured in the engine or come through the hole when the pump is removed.

 

[Capt Paul]

I have 4-53's in my LRC. As I recall, I just pulled the pump bolts, removed the pump and replaced with the new one and tightened the bolts. I don't recall having anything fall off or anything that concerned me. I will be on board Monday and can take a closer look along with inspection of a replacement pump to be sure if you haven't done it or gotten definitive 4-53 advice by then.

 

[cb48lrc]

We finally stopped moving long enough to replace the raw water pump. A relatively easy job, inlet and outlet ports are 2 bolt flanges and the 3 pump mounting bolts the pump will then just pull out of the adapter. New gaskets and the job is completed.