1973 Evinrude 9.5 Water pump issue

[bruisedreed]

So really haven't been able to get anywhere with this issue. Started with a motor that was pumping water, just not as much as I thought it should. Replaced the impeller and had NO flow after. I have been slowly acquiring all the parts I can think of that have anything to do with the cooling of the engine but I just can't make it work. I put the old impeller back in the pump, nothing. I can't figure why I cant get the pump to gulp manually with the lower unit submerged. The parts diagram shows the gasket around the driveshaft (0309607) and a washer seal (0309583) above it. The gasket was in the water pump when I initially took it out but there was no washer. My question is that gasket does NOT fit tight to the shaft. I can't really figure what it does other than create a little dampener or skirt inside of the shaft passage through the pump. SEE ATTACHED PIC...this illustrates what I'm seeing (notice the gap between shaft and seal. Is it possible this isn't the right seal? I'm not sure that is any issue, but I can't see anything else that wouldn't make this pump. there aren't any other parts to it really. Impeller is turning, key is in the shaft water passages are clear. I'm really stumped.

 

[RCO]

Did you take the pump base plate off? It's possible to install upside down, same with the gasket under it. That would block the water intake passage to the impeller. Also pull the side water intake cover to make sure nothing is stuck in the passage from the water intake screen below, or the passage to the impeller above it. The two o-ring seals you are describing won't prevent the impeller from pumping. Any chance the water tube pulled out of the powerhead? That is very common on the 9.5, and is tricky to get it reinstalled without removing the powerhead.

 

[bruisedreed]

Did you take the pump base plate off? It's possible to install upside down, same with the gasket under it. That would block the water intake passage to the impeller. Also pull the side water intake cover to make sure nothing is stuck in the passage from the water intake screen below, or the passage to the impeller above it. The two o-ring seals you are describing won't prevent the impeller from pumping. Any chance the water tube pulled out of the powerhead? That is very common on the 9.5, and is tricky to get it reinstalled without removing the powerhead.

Thr water tube is off now...but that is secondary at this point. I am hopeful with a borescope I can get that back without the powerhead coming off but we will cross that bridge when we get there. manually I cant get the pump to lift at all when I rotate the shaft with the lower unit submerged. The plate is oriented properly and all passages are clear. I will go through it again and make sure but I just cant seem to get this.

 

[racerone]

The impeller must be submerged., the pump is not self priming.

 

[F_R]

The rubber seal on top of the pump should have a brass insert washer inside it. These parts are very important. They keep smoke from going up through the drive shaft isolation tube and coming out under the hood, smothering the motor to where it will barely run.

 

[bruisedreed]

The rubber seal on top of the pump should have a brass insert washer inside it. These parts are very important. They keep smoke from going up through the drive shaft isolation tube and coming out under the hood, smothering the motor to where it will barely run.

yes. it does now. probably why I had as much smoke as I did the first time it ran.