so after doing a great job of replacing damaged impeller. thought i primed the pump filling strainer. engine ran for 2 minutes before i shut off. pump definitely got hot as hell. question is. is it shot? i unhooked hose going to pump from strainer. after 2 quarts topped off. i guess thats what i should have done.
started dry impeller 120 leahman
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RT Firefly
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Greetings,
Mr. W. Best take off the cover and examine the impeller IMO.
Mr. W. Best take off the cover and examine the impeller IMO.
Mambo42
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Better check that impeller again, running without water will destroy it in no time.
When you put the new impeller in throw some dish washing liquid in the pump from the top connection. That will lubricate the impeller in the start up phase. I never primed the pump itself, just let the water come up in the hose to the water pump (by opening up the sea cock) before I connected the hose to the pump. Then you open up the sea cock and water will enter into the pump by itself. After that just started the engines, lots of foam comes out of the exhaust, but that is it.
When you put the new impeller in throw some dish washing liquid in the pump from the top connection. That will lubricate the impeller in the start up phase. I never primed the pump itself, just let the water come up in the hose to the water pump (by opening up the sea cock) before I connected the hose to the pump. Then you open up the sea cock and water will enter into the pump by itself. After that just started the engines, lots of foam comes out of the exhaust, but that is it.
lol yep.
i didnt mess with the seacock.
mine comes from seacock up to sea strainer down to pump. when i opened pump it drained that hose from strainer. i tried filling strainer to top and than recap. i guess it didnt fill the hose to the pump. took hose off... empty. i filled hose hooked back up. just deciding if i should try it. i bet it works now.
rgano
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Can you lower that sea strainer?
psneeld
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If the pump got hot, the impeller without lube, water or a silicone based material is always probably damaged to the point I wouldn't trust it. Good that you replaced, even if you THOUGHT it looked OK.
If you lost any blades you will need to get those out. I have disconnected sections, and used an inflatable tender foot pump and worked my way forward through the system collecting blades as I went. Buy a couple of extra impellers for ships stores.
I have been tempted to try silicone impellers instead of the older fashion ones. The are supposed to be more heat resistant and give you a little more time to discover the problem before they self destruct.
I have been tempted to try silicone impellers instead of the older fashion ones. The are supposed to be more heat resistant and give you a little more time to discover the problem before they self destruct.
Comodave
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I use a silicone grease when installing an impeller. It helps insert it and gives it some lube while the pump is priming.
OldDan1943
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And that is why it is best to mount the pump below the water line and fill the strainer body with water. I say this based upon experience with my A/C S/W pump. Make sure the hose in and out of the pump is not impeding the water flow
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psneeld
Guru
A/C pumps often are not self priming and HAVE to be mounted below the waterline. Impeller pumps for engines do not, and with a well sealed impeller may not flood anyhow.
Many engines have the water pump gear driven and mounted to the engine.
Thus the repetitive suggestion to lube the impeller upon installation and immediately check for water flow. Once run enough water is usually retained in the pump to keep it from overheating till water reaches the pump.
Long term storage should be viewed towards that the impellers should be primed/lubed after the impeller is checked and the lines and sea strainers are full to the waterline.
Many engines have the water pump gear driven and mounted to the engine.
Thus the repetitive suggestion to lube the impeller upon installation and immediately check for water flow. Once run enough water is usually retained in the pump to keep it from overheating till water reaches the pump.
Long term storage should be viewed towards that the impellers should be primed/lubed after the impeller is checked and the lines and sea strainers are full to the waterline.
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Glycerin will eliminate the soap bubbles
Mambo42
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It will, but dish washing liquid was easy to get, is cheap and does the job. A long term engine mechanic taught me the trick, have been using it ever since. I had foam coming out of the exhaust for about 5 min and that was it.
kapnd
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If it got hot, I’d be having a look at it. Water based lubricants are great for impeller installation, it won’t affect the rubber, and washes away quickly once flow is established.
I mount the strainer so that its top is just slightly above the resting waterline. It’s self filling, but won’t overflow into the bilge when opened for cleaning, and I’ve never had to prime the pump, even though it is a few inches higher than the strainer.
I mount the strainer so that its top is just slightly above the resting waterline. It’s self filling, but won’t overflow into the bilge when opened for cleaning, and I’ve never had to prime the pump, even though it is a few inches higher than the strainer.
