impellor 1965 33hp johnson

[jay_61074]

i replaced the impellor on this motor a month or two ago because it wasn't moving water. the new impellor worked great as i was running it in a water barrel then it stoped working and i found the rubber impellor torn to pieces. did i do something wrong? i thought i kept enough water in the tank to feed the pump.

 

[tashasdaddy]

Re: impellor 1965 33hp johnson

those motors have to be submerge in a tank, 1/2 way up the leg. there have been many destroyed that way. i have several on my list.

 

[tassie ben]

Re: impellor 1965 33hp johnson

the water in your barrel should really be above the waterpump itself, not just the intake....although, it seems something else other than a short blast with no water may have chopped up your impeller....unless of course you had it running for a while??? The turbulence created will in effect lower the intake water level in the barrel also so trick is to keep it high..

 

[jay_61074]

Re: impellor 1965 33hp johnson

well i think the water may have got low in the tank for a short while . and i was getting alot of turbulance in the tank while i was working on a problem with low rpms on the motor. the motor wont run at full rpm's with the hand throttle but will if i move the linkage at the carb.?

 

[jay_61074]

Re: impellor 1965 33hp johnson

the water in your barrel should really be above the waterpump itself, not just the intake....although, it seems something else other than a short blast with no water may have chopped up your impeller....unless of course you had it running for a while??? The turbulence created will in effect lower the intake water level in the barrel also so trick is to keep it high..

well i think the water may have got low in the tank for a short while . and i was getting alot of turbulance in the tank while i was working on a problem with low rpms on the motor. the motor wont run at full rpm's with the hand throttle but will if i move the linkage at the carb.?

 

[samo_ott]

Re: impellor 1965 33hp johnson

Was it a Sierra or OMC impeller?

 

[jay_61074]

Re: impellor 1965 33hp johnson

well.. i used the omc part number and it looked the same.

 

[tassie ben]

Re: impellor 1965 33hp johnson

I reckon the issue was from low water and possibly inferior impeller material like samo might be implying??
Try blasting air through your tell tale and blowing anything back through the pipes the opposite way it as come?? An idea. Its what i did. I could feel air blowing out through the intake pipe at about the same psi so i assume its clear...

 

[jay_61074]

Re: impellor 1965 33hp johnson

i will i just don't see what would tear the impeller to small peices like that.

 

[F_R]

Re: impellor 1965 33hp johnson

If it was from lack of water it would show signs of heat or abrasion on the rubber. Imagine what a pencil eraser does when you rub it across the paper, or a tire on the road when you slam on the brakes.

If it just blew to bits from no other reason, I would be camped on the seller's doorstep first thing in the morning. Inferior material or very old stock, I would say. Motors that have been sitting around for years do that very same thing.

 

[jay_61074]

Re: impellor 1965 33hp johnson

ok thanks for the replies i will replace impeller with omc and make sure water levels are plenty high in my test tank.

 

[jay_61074]

Re: impellor 1965 33hp johnson

so i got the new impeller and installed it cleared out all of the debris from the old impeller. started motor and still no water flow(plenty of water in tank). took off lower unit again, and blew co2 both ways through the water tube and through the exhaust and felt air flow both ways. put back together and still no water flow! whats the next step?

 

[tassie ben]

Re: impellor 1965 33hp johnson

you felt air in both directions, did it equal the same pressure being exerted?
It could be that the water is getting up there but not exiting the tell tale..did you have a good seal between the impeller housing and the water uptake tube?? I have just re read your post, you said you blew it through the exhaust...do you mean the tell tale hole or "the exhaust".. if it was the exhaust, try blowing air through the tell tale and you should feel it exiting through the water tube.

any one else have any ideas??

 

[tassie ben]

Re: impellor 1965 33hp johnson

another thought, you did have the "key" in the drive shaft, if this is missing the impeller will not move at all...not meaning to state obvious just covering all bases. Also from original post, it may have been your impeller was replaced back to front which would explain the vanes breaking off??

 

[jay_61074]

Re: impellor 1965 33hp johnson

i did make sure the key was in and used the suggestion in the manual to turn the shaft clockwise while putting the housing back together to make sure the vanes are not pinched. i blew it back through the exhaust and did feel air through intake tube, not sure it was good flow however. but i would thing that i would at least get a dribble of water when runb in water

 

[jay_61074]

Re: impellor 1965 33hp johnson

whatis the tell tale and what do u mean by "back to front"

 

[jay_merrill]

Re: impellor 1965 33hp johnson

This motor doesn't have a telltale.

 

[jay_61074]

Re: impellor 1965 33hp johnson

back to the drawing board: i guess i will take it apart again...

 

[tassie ben]

Re: impellor 1965 33hp johnson

jay merril answered one question for me, no tell tale.
The answer to second , is the aussie way of saying "wrong"...
to put in context the shaft moves clockwise and so the impeller vanes need to move one way only. if you placed the impeller so that the vanes were bending against the "clockwise" direction of the shaft then this would be what we call "back to front" a figure of speech here (you would be right to think there was no back or front in regards to the impeller)

 

[tashasdaddy]

Re: impellor 1965 33hp johnson

impellers usually correct themselves. you have a hole on the back of the leg, 1/2 up. that is the exhaust relief port, you should have mist, or droplets coming there. that is the tale tell on that motor.