No Raw Water Flow To The Generator

[Chuck Hawley]

If you have Marelon seacocks, I would look at the L that is often attached immediately above the ball valve. I have seen this area be completely full of grass (Marina Cay, BVI) so that no water could even get to the strainer, yet I could have blown through the clog. This may require that you remove the seacock from the hull, and thus have to put your foot or a sponge or some other item where the seacock used to be as you clean it. Or haul out.

Chuck

[Cadence]

Originally Posted by enjaku

I have a Paguro 4000 generator onboard that is not getting any raw water flow.
1. The sea cock is open
2. I can blow air through the intake hose at the strainer and hear air escaping underneath the boat.
3. If I remove the impeller and cover, I can blow air from from the strainer through to the pump, so I know the hoses are clear.
4. The strainer is clean
5. I replaced the impeller twice with the same affect. The impeller appears to be seated properly and is undamaged.

I do not see any raw water in the strainer when the generator is running, and the generator soon shuts down as it starts to over-heat.

Any thoughts?

My guess would be that you have growth on the intake. Yes, you can blow air out but is acting like a flapper valve closing on the intake suction. I quick swim with a stiff brush may solve it. JMHO

[bill99]

I once had the same problem. Took a long time to find the answer. In my case a baby shellfish had lodged itself inside the intake tube and then slowly grown in size until it blocked the intake. Now whenever I take the boat out of the water for antifoul, I take the protective screens off the hull that cover the intakes, and with a long screwdriver scrape the inside of the intake tubes for all intakes including toilets etc..

[waterman46]

You should be able to clear any thru hull without going swimming or hauling out: Close the seacock, disconnect the attached plumbing then attach a piece of tubing to the seacock using the correct straight hose barb. Tubing must be long enough to reach a little above waterline inside the boat. Secure the tubing so the end is above waterline, then open the seacock. Now just use a piece of rigging wire into this tube, as a plumbers snake, to clear out the thru hull.