Overheating/no stream of water

[Harley558]

This thread is only for the smart ones; that is, if anyone can figure this one out.

I have a 1997 Mercury/Mariner 15 h.p. outboard. 0G522668

I purchased the motor over the winter and was told it ran good. He ran it for about a minute to show me then shut it down.

I went to put it in the water a few days ago and noticed there was no stream of water coming out the cooling hose. I shut it down and took it back home.

I replaced the 120 degree thermostat and it's gaskets. I then replaced the impeller which the old one looked as good as the new one. I then blew air (110 p.s.i.) in the chambers. First up the cooling outlet and it was clear to the thermostat. I then blew air down the thermostat hole and can hear and feel the air coming out the bottom. I then did the same on the little holes at the bottom fo the casing where the water goes in.

I put it all back together, stuck the body in a large bucket and started it up. After the thermostat opened, I onlyu got steam again. No sream fo water coming out the water/cooling exit.

What can be wrong?

HELP!!!

 

[Jeep Man]

Re: Overheating/no stream of water

Didn't say you tested or replaced the pump!!

 

[Harley558]

Re: Overheating/no stream of water

Pump? Do you mean the impeller? I replaced it!

 

[saumon]

Re: Overheating/no stream of water

Thermostat only change the flow path of the water, not the quantity, so it can't be this. I only think of 2 things that can cause a no water condition:

1 - Is the key preventing the impeller to spin around the driveshaft in place?

2 - Is the seal joining the pump housing and the water tube misaligned?

 

[StefanV]

Re: Overheating/no stream of water

Hi!

Are you sure there is no other hole a bit higher up in the leg where it is taking air instead of water?

Stefan

 

[Harley558]

Re: Overheating/no stream of water

No other holes after the bottom housing connects to the long neck. I submerged the hole bottom housing.

 

[machinist247]

Re: Overheating/no stream of water

The witness stream hole on these motors sometimes gets blocked off by salt crystals.I have to clean mine on a regular basis with small piece of wire.remove rubber hose from head hold it strait and push wire through.not sure if this is where you blew air into.if u did it's not that then.