Raw water pump repair and issues.

[SorinCT]

Hi!
Just lowered my boat in the water for some trials and upon starting i had no flow of sea water coming from the pump (jabsco type, neoprene impeller, pulley drive). The pump was dismantled and a new cam fabricated according to original specifications. Turns out that after repair... the spray of water from the aft is quite strong, spraying at about 3 meters regularly and sometimes sending some drops at 6 meters distance. Impressive but not practical.
Exhaust system is wet type. The gases and water flow into the muffler and then directly into the exhaust pipe at the aft, with no goosnecks or other fittings.
How do you suggest i should deal with the problem? Try to install some water trap/goosneck or just simply direct the flow of water a bit downwards from the aft pipe?

Smooth sailing!

[Lepke]

You only need enough water going out the exhaust to cool and muffle. Many engines divert about 1/2 the water directly over the side. My mains do this and also send some of the water to behind the shaft seal (to force lubricate the stern bearing).

[HopCar]

You made your own cam! Very cool, but I suspect it may be a little thick. If I'm right, your impeller will have a shorter than normal life.

[SorinCT]

Thick or not, the cam was made to spec with a new Jabsco pump for reference. I am already starting to prepare an emergency repair kit for the engine so i will have a spare impeller in stand-by all the time.
My system is set up to send part of the water to the shaft seal so not all the water is going to the exhaust side. I will check exactly how much water is going there by removing the hose and filling a 5l bottle... maybe there is not enough flow.