1973 45hp Chrysler went through another impeller ???

[pbiwolski]

I had a recent carb issue which has (I believe) been resolved. I was no-wakin' away from the docks and listening to a nice, smooth idle and low-speed purr, but no water was being pumped. I kept checking it and nothing. I revved it up quickly and shortly, but nothing. It was getting hot, so I shut it off.

At home I found the inner core of the impeller to be melted down onto the bottom plate of the pump. Some vanes were splitting away as well. The drive key was bent (again?) and even bored a slot horizontally around the interior of the impeller. I had already gone a round with this pump (here), and thought I worked it all out.

I've been running it in the backyard in a tub (probably not deep enough - it covers the anti-cav. plate by about two inches). Do you suppose I burned up the impeller when I was sorting out my carb issues in the backyard? Did it get too hot that the key spun right through the thing? Does anyone have any experience with these symptoms?

I'd like a reply before I get another key and impeller and do this all again!

PS - I'm pretty certain the impeller is the right one for the pump. I don't think that is the issue.

 

[BuzzStPoint]

Re: 1973 45hp Chrysler went through another impeller ???

You could have possibly burnt it up.. It doesn't take much to melt these things.

Do you recall how long it took for the water to start spitting out the exhaust when you had it in the tub for carb testing?

With my 55hp, I have to put it in a garbage can and have the water more then 1/2 way up the leg.

Either way it's time to remove the lower unit. Pay close attention to the pump housing, Is there anything there that could be causing the impeller to shred itself? Big scores and scratches?

 

[pbiwolski]

Re: 1973 45hp Chrysler went through another impeller ???

Alright, I ordered another key and impeller. I'll give it another shot, and find a deeper tub! Thanks.

 

[catfishcarl99]

Re: 1973 45hp Chrysler went through another impeller ???

Alright, I ordered another key and impeller. I'll give it another shot, and find a deeper tub! Thanks.

ya i started my 50 force up a few times one summer for just a few seconds to see how it idled while i was doing carb work. i found out the hard way that new impellors can burn up within 30 seconds. sounds like the tub might need to be higher. a couple inches above plate may not be enough to submerge the housing.

 

[jerryjerry05]

Re: 1973 45hp Chrysler went through another impeller ???

You need at least 4 inches above the line where the lower and the upper meet.
The older 35-60's and some others need a special muff.
If you don't have a big bucket.
Now that youv'e burned up the impeller ,you need to check the tube going to the motor for pieces of hose and blockage.

 

[wickware]

Re: 1973 45hp Chrysler went through another impeller ???

It takes almost a full 55 barrel to be as deep as being the lake and I get instant water(with my 1970 35 HP Chrysler). If I'm 2? off, no water.

 

[pbiwolski]

Re: 1973 45hp Chrysler went through another impeller ???

Yeah, didn't realize it was the impeller at first because I had recently replaced it. So I started trouble shooting by taking off the short hose (?) on the motor and flushing the "2nd half" of the system downward. No debris or blockage there (of course it wouldn't be that easy), so I took off the L/U and flushed from the tube upwards to the hose, and found nothing there. It had to be in the water pump, and of course, the impeller was shot.
I already received my impeller and key, so I should be good to go tomorrow evening!