Urgent - Raw Water Pump Not Working!

[Don1500]

Ran for 30 seconds with the output hose disconnected, no water in bilge. It's not pumping. I am going to remove the input again and see if I can blow to the strainer.

[Don1500]

Originally Posted by atoll

if you can try sucking some water thru before turning over the engine,not very nice but at least you will know the pump is primed

Can't get to the hose to suck on it. (Don't know how hard I would try really.)

[atoll]

Originally Posted by Don1500

Ran for 30 seconds with the output hose disconnected, no water in bilge. It's not pumping. I am going to remove the input again and see if I can blow to the strainer.

with the seacock open you should be able to hear air bubling on the outside of the hull if it is clear

[Don1500]

Originally Posted by atoll

is the heater linked in any way to the engine,ie shared seacock?

No, opposite end of the boat. Two separate systems.

[Don1500]

Originally Posted by atoll

with the seacock open you should be able to hear air bubling on the outside of the hull if it is clear

Water fills the strainer as soon as I open the sea cock. I also opened the sea cock with the strainer off, got my bilges wet.

[atoll]

Originally Posted by Don1500

Water fills the strainer as soon as I open the sea cock. I also opened the sea cock with the strainer off, got my bilges wet.

is the anti siphon between the strainer and the pump?

[Don1500]

I am thinking bad pump shaft. That's to hard to do in the dark. I have been doing everything using the Helen Keller method up to here. I have the overhaul book so I should be able to do it without removing the engine, just need to get to it. That will be tomorrow morning.

[Don1500]

Originally Posted by atoll

is the anti siphon between the strainer and the pump?

No, the anti siphon is on the out put of the heat exchanger.

You're right about the ball and stuff. I remember how it works now.

[atoll]

Originally Posted by Don1500

I am thinking bad pump shaft. That's to hard to do in the dark. I have been doing everything using the Helen Keller method up to here. I have the overhaul book so I should be able to do it without removing the engine, just need to get to it. That will be tomorrow morning.

seems unlikely,as the lip seal would have been leaking out the pump housing,.
though it is possable the shear pin has sheard in the gear housing on the pump shaft.

or front plate is very worn.

will be online til later or tomorrow if you need mor ideas!

[sailorchic34]

Have you tried a different impeller and is the O ring on the speed seal cover good. You know when they say cruising is fixing the boat in exotic places, its true.

[colemj]

Do you mean you took the outlet hose off the pump housing and no water pumped out?

I have had impellers spin their bushings before. If you have a replacement impeller, put it in and remove that possibility from the problem.

Also check the inside of the pump to make sure the cam is still in place (that little raised bit that makes the impeller squeeze up and suck water).

If the shaft is turning, and the impeller is good, and the cam is there, and there is a good seal on the cover, it has to pump water.

Mark

[cal40john]

Originally Posted by Don1500

I am thinking bad pump shaft. That's to hard to do in the dark. I have been doing everything using the Helen Keller method up to here. I have the overhaul book so I should be able to do it without removing the engine, just need to get to it. That will be tomorrow morning.

Didn't you say earlier that the key in the impeller was in a different place after cranking the engine? If that's true I don't think it's the shaft. Can you rig a local start switch so you can watch the impeller turn since you're alone. Simplest is a screwdriver across the solenoid.

If your pump is well above the waterline all seals have to be tight for the pump to prime. Someone on CF said he had to prime his, but that indicates an air leak in the pump or the suction side.

John

[atoll]

Originally Posted by colemj

Do you mean you took the outlet hose off the pump housing and no water pumped out?

I have had impellers spin their bushings before. If you have a replacement impeller, put it in and remove that possibility from the problem.

Also check the inside of the pump to make sure the cam is still in place (that little raised bit that makes the impeller squeeze up and suck water).

If the shaft is turning, and the impeller is good, and the cam is there, and there is a good seal on the cover, it has to pump water.

Mark

ditto that,just a thought there is no way you could have swapped the inlet and outlet hoses over by accident

[Don1500]

1. I have another impeller, it's put away in a safe place in case I need it.
2. I have new seals and I will change it but the first time I took off the cover a small amount of water came out and it was dry on the outside.

[CarlF]

I don't think you've positively ruled out the hose, strainer, or fittings along the hose (is there a 90 degree fitting coming out of the strainer)? Is the gasket on the strainer cap truly air tight? It's quite possible to have a clog where you can blow air one way but water can't be sucked the other way.

I'd try one of the following:

1 - Take the hose off the raw water pump inlet. Tape a manual bilge pump on the hose with duct tape and pump water.

2 - connect a short piece of hose to the raw water pump inlet and put it in a bucket of seawater in the bilge. Start the engine and see if you can empty the bucket.

Carl