'72 50HP Johnson, water pump working correctly?

[Hoyt79]

Not sure how to tell if my water pump is working correctly. I installed a new impeller, cleaned up the pump and installed it back per the service manual. I put the lower unit back on last night and ran it at idle with muffs. Water is coming out of the slits above the cavitation plate as normal. I filled up a barrel with water and ran it in that at idle and I have water coming out of the exhaust port midway up the motor also. I felt around the motor to get a sense of the temperature and just aft of the metal 'eye' that you pick the motor up with if I put my hand on that area, I can't keep my hand on it it is hot. under the flywheel on the side of cylinder wall it is warm and I can keep my hand on it. the area around the spark plugs is warm and can keep my hand on it...its just that area on top between the flywheel and the metal 'eye' or ring that you hoist the motor up with. Is it working properly or what?

 

[Daviet]

Re: '72 50HP Johnson, water pump working correctly?

Your engine does not have a tell-tale, a visual indicator of water pump pressure, you have to rely on looking at the water coming out of the exhaust ports with the engine in the water. Running on muffs you will have very little if any water coming out of the exhaust ports. Make sure you overheat horn is working, do you know how to test it?
You can install a tell-tale, do a search, there are quite a few posts on it.

 

[Hoyt79]

Re: '72 50HP Johnson, water pump working correctly?

Your engine does not have a tell-tale, a visual indicator of water pump pressure, you have to rely on looking at the water coming out of the exhaust ports with the engine in the water. Running on muffs you will have very little if any water coming out of the exhaust ports. Make sure you overheat horn is working, do you know how to test it?
You can install a tell-tale, do a search, there are quite a few posts on it.

I don't know anything about an overheat horn...where is that located? On the engine itself? How do you test it?

 

[emoney]

Re: '72 50HP Johnson, water pump working correctly?

Mine is located in the controls and it's a "buzzer" as opposed to an actual horn. Harbor Freight sells an InfraRed Temp Guage for about $30.00 and it's a very handy tool to have. I was worried about overheating as well and these guys recommended I buy one and use it. Come to find out, she was operating as normal. I wouldn't put all my faith in the "touch" test, because everyone's idea of "too hot to touch" is probably a little different.

 

[Hoyt79]

Re: '72 50HP Johnson, water pump working correctly?

Mine is located in the controls and it's a "buzzer" as opposed to an actual horn. Harbor Freight sells an InfraRed Temp Guage for about $30.00 and it's a very handy tool to have. I was worried about overheating as well and these guys recommended I buy one and use it. Come to find out, she was operating as normal. I wouldn't put all my faith in the "touch" test, because everyone's idea of "too hot to touch" is probably a little different.

Is the buzzer standard equipment on the control box?