Difficult time with the old polaris this summer, mainly with drive mechanism rather than pick-up as it will clean but will not climb well and travels slowly. Took it into the pool store and they did their basic tune up of replacing drive belts and whatever else they do for 30 bucks or so. Still slow.

Had a service company out to replace some valves covered under my home warranty and spoke with them. They swore it was a pump and motor problem though I was totally unconvinced. However, since minimal cost to me with a $45 deductible gave them the go-ahead to replace the pump and motor. Replaced with identical unit and had identical problem.

I've opened it up including taking off the inner housing and couldn't find anything askew. Venturis working fine and seems as though hose pressures are fine though I have not measured for the 32(?) psi. Cleaned screen, and tried running without the restrictor plate. Back-up valve working fine and replaced joints in the hose that appeared to be working fine.

Here's the interesting part: When I pull the whole unit out of the water the drive mechanism and the power of the wheels feel strong. As soon as I submurge the unit (or just the side with the drive mechanism - the jet and little turbine wheel) the performance dies. The wheels slow significantly and have no power to resist me holding them. (When I ran it without the housings on it appears to me that the only about 1/3 of the jet that hits the drive turbine actually hits the turbine; it almost seems that it is not hitting it directly enought, yet there does not seem to be any adjustment to relocate the jet so it contacts the turbine wheel better.)

Next step is to try to reach polaris customer service but I won't get a chance to do that until next week.

So, question is, any idea what is wrong? Any idea of the siginficance of in-water vs. out of water performance? Any thoughts or suggestions appreciated.