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by Papageorgiou
(Rockville, MD)

I have a SPEEDAIRE 3Z323 compressor That I bought from Grainger about 35 yrs ago. Great service through the years.

Yesterday, after removing the DAYTON capacitor a/c motor and the cast iron pump (in units no disassembly) for repairing a pin hole in the side of the tank, I re-installed the motor and pump.

The compressor started working fine for about 35 seconds and pressure was indicating 40psi when the pump started slowing down sounding stressed and tight and the motor (DAYTON Capacitor A/C Compressor, V 115/230, A 17.8/8.9) made some screeching dry noise in the area of the axle (point of belt turning) although the belt tension was proper. I turned the power OFF immediately.

After removing the belt, I could spin the motor freely by hand. With the belt OFF, I turned the power ON and the motor was spinning on high rps without any noise. Turning the power OFF again the motor spinning slowly went down and came to a stop without any stress or noise. Oil was changed about 2 weeks ago and level is to top. I appreciate your input. Thanks. George

Hi George…

I hope you are really good with a welder. It is not normally a good idea to try and repair a leaking compressor tank. The pinhole indicates that there is internal rust damage to the tank wall, and you may have the potential for a catastrophic failure along the way.

I would replace the tank myself as welding one spot will not fix other weak areas, and the welding process may damage an already weak wall further.

The absence of a photo of the compressor makes it hard for anyone to provide specific help as to the motor bogging down now, when it did not before. I

f nothing else on the compressor or the power supply has changed, I suspect that the check valve from the pump head into the tank has been compromised. That possibly happened when you were moving the tank around to fix it, and lots of tank crud got into the check valve and maybe prevents it from opening properly.

That’s my first guess, George. Maybe check that out and then post if that was the problem or not as a comment here?

Motor bogs down
by: George

Hi Bill,
Thank you for your suggestion regarding possible air pressure valve failure. I was suspecting that but I had taken no action as to exploring it. After your suggestion, I will definitely check it out and post the result. Also I will look for another tank. Thanks,
No problem, hope I helped.


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