impeller fins torn off of new impeller

[dave37]

had my prop shaft straightened at a local shop a couple of months ago, haven't used the boat since. Went to winterize it today and no output from the pee hole and not a whole lot from around the prop. Shut it down, took water pump apart and the impeller fins were all completely torn off (not melted) at where the rubber fin meets the impeller.

The only thing I can think of is that when they reassembled it they had the fins pointing the wrong way inside the pump, and they tore off on start up could there be any other reason?

 

[Laddies]

Re: impeller fins torn off of new impeller

My guess would be they tightened the housing down without turn the shaft and caught the tips of the imp blades, when installing a new impeller there is no wrong rotation as the blade will flip over with no damage, on used impellers they have developed a set and reversing one will break the blades

 

[dave37]

Re: impeller fins torn off of new impeller

It was a used impeller, it was only a couple of months old when the prop shaft was straightened so they reused it. If as you point out it had developed a set in, then if they put it in the wrong way that would likely be why they tore off?

 

[Scaaty]

Re: impeller fins torn off of new impeller

It was a used impeller, it was only a couple of months old when the prop shaft was straightened so they reused it. If as you point out it had developed a set in, then if they put it in the wrong way that would likely be why they tore off?

My take is yes...

 

[Jimmy70]

Re: impeller fins torn off of new impeller

It is my understanding that the impeller should be screwed into place clockwise as if you put them in counterclockwise it will rip them off. This was told to me by the mechanic and the manual says the same thing too.
Jimmy70

 

[Laddies]

Re: impeller fins torn off of new impeller

Jimmy, I have been putting them in for 40+ years and will tell you again, on a new impeller there is no way to damage it by putting it in the wrong way

 

[imported_skraps]

Re: impeller fins torn off of new impeller

Laddies has that right i have done it to see,and they reverse as soon as water hits them.

 

[Scaaty]

Re: impeller fins torn off of new impeller

Laddies has that right i have done it to see,and they reverse as soon as water hits them.

Yep, and old will take a set REAL quick, and if put in backwards..well..toast

 

[dave37]

Re: impeller fins torn off of new impeller

thanks guys, the repair shop in question has agreed to replace the water pump impeller.

 

[dave37]

Re: impeller fins torn off of new impeller

The repair shop gave me the needed parts, but I don't have a good feeling about these guys. The mechanic there told me not to worry about having run it at idle for about 5 minutes without a working water pump--I wasn't concerned at the time as it frequently gets a plugged pee hole from spiders. The water jacket got warm to the touch, should I be concerned about any overheating when I was running it or not worry as the repair shop claims.

 

[j_martin]

Re: impeller fins torn off of new impeller

I think I'd check it out a bit before you put it away.

Check spark plug tightness, they'll loosen up a bit if it's grossly overheated.

Check head bolt torque, a couple of loose ones near the top is a warning sign. You don't need to feel them turn, just that they are tight enough. In other words, don't overtorque them more if they are a little tight to begin with. Just bring the needle up to torque and back off, seeing if the bolt turns.

Float it and take it for a ride, then pull the plugs and make sure they are all a bit dirty, not "steam cleaned." Take a peek in the holes at the same time, if one piston top is nice and clean, and the rest are dirty, you got trouble.

Odds are about 1 in 10 or 20 you hurt it, but it's sure worth being sure.

In the future, I wouldn't worry too much about the pee stream, but there better be some water coming out the prop.

hope it helps
John

 

[dave37]

Re: impeller fins torn off of new impeller

I'll have to try next season, the river is too low here right now. I fogged the motor and it ran great as usual (put a garden hose on the water pump tube as the lower is off)

Out of paranoia, I pulled the plugs and checked inside the cylinders, all looks good. Guess I'll have to refog (probably removed a lot of the fogging oil turning the motor over by hand to inspect)