Fixing old pond pump

[clubkemp]

2 years ago I purchased a property with a big koi pond and inherited a non-functioning pump. I was finally able to get it running after replacing some of the piping, but now have encountered a new problem.

Someone down the line had installed the impeller and plate together without stainless steel hardware so those suckers rusted out and everything got shredded on the wet side of the pump. The housing reads as Challenger PAC-FAB5HP (CFII-N1-5FE) so I bought replacements parts for a 5hp motor (replaced everything between motor and housing). I got all that together and fired her up and the thing cranked way more water pressure than I had ever seen it. After about 5min it starts to oscillate a bit and doesn't smell right, like overheating electronics, then eventually shuts off.
I actually just looked at the motor itself and it says it's an A.O SMith MOD. K48M2PA104A2 1 hp. Now I am thinking somewhere down the line someone pump in this motor instead of a 5hp pump and after reading in this forum it makes me think the motor is undersized, working too hard and overheating. Does that theory sound correct? If yes do you think the best course of action is to actually order parts for a 1hp motor (in which case I would probably have to get the correct housing for it??) OR do you think I should buy a new 5hp motor? Any other potential issues?

 

[1poolman1]

2 years ago I purchased a property with a big koi pond and inherited a non-functioning pump. I was finally able to get it running after replacing some of the piping, but now have encountered a new problem.

Someone down the line had installed the impeller and plate together without stainless steel hardware so those suckers rusted out and everything got shredded on the wet side of the pump. The housing reads as Challenger PAC-FAB5HP (CFII-N1-5FE) so I bought replacements parts for a 5hp motor (replaced everything between motor and housing). I got all that together and fired her up and the thing cranked way more water pressure than I had ever seen it. After about 5min it starts to oscillate a bit and doesn't smell right, like overheating electronics, then eventually shuts off.
I actually just looked at the motor itself and it says it's an A.O SMith MOD. K48M2PA104A2 1 hp. Now I am thinking somewhere down the line someone pump in this motor instead of a 5hp pump and after reading in this forum it makes me think the motor is undersized, working too hard and overheating. Does that theory sound correct? If yes do you think the best course of action is to actually order parts for a 1hp motor (in which case I would probably have to get the correct housing for it??) OR do you think I should buy a new 5hp motor? Any other potential issues?

If you put a 5hp impeller on a 1hp motor, as you can see, it won't work. Probably had a 1hp impeller that you replaced. Pac Fab pumps had varying diffusers and the spacer below it depending on horsepower. Since the motor you now is likely very damaged due to overheating, you could go ahead and get 1hp parts but be prepared to need a new motor if you can find one. You don't mention your location, but if in the US, those single-speed motors are no longer legal and many places will no longer ship them. If in California, they definitely won't.