I was unable to contact the moderator and it does not seem possible to post attachments on this forum, so I will bravely post my email address here if you want photos.
samusante(at)comcastDOTnet
replace (at) with @
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After receiving responses to this message I decided to dig further into this problem. It bothered me that I saw so little wear on the switch lever. I just could not believe that this unit was designed with such a small margin of operational tolerance. I thought it looked odd that there was a retaining washer on the shaft that was not really performing any function. My hunch was that the centrifugal actuator assembly had originally been out flush with the retaining washer. By pushing on the phenolic disk it was obvious that the disk more or less slams against the back of the assembly when the motor starts. This could create the effect of a slide hammer and possibly move the assembly up the shaft by a tiny increment each time the motor started. I did not want to break any of the plastic parts of the actuator but I had to know for sure so I put a couple of pry tools behind the base of the actuator, and with much less resistance than I expected, the actuator slid forward into the retaining washer.
I was happy to find the root cause of the problem but I was also disappointed by the reality of how rinky-dink this problem is. The actuator assembly consists of a molded glass-filled nylon sleeve and carrier that the springs, weights and phenolic disk are attached to. The assembly itself seems well made. The sleeve is a tight enough press-fit to guarantee that it will spin with the shaft and not slip under starting torque. (normally you would use a keyway to prevent this) All it would take is a snap ring groove and snap ring on either side of this actuator to prevent the actuator from moving on the shaft and make this a long life motor.
Unfortunately the manufacturer opted for cheaper retaining washers to position the assembly on the shaft, and I don't know if they were supposed to use a retainer on the back side of the assembly or not, or if there was supposed to be a spacer sleeve to prevent movement of the assembly. Mine did not have either and I would say that others may have the same problem. If they were all built this way then it is all a matter of how tightly the actuator fits on the shaft. If it is very tight then they may never see a problem.
I also have a theory that the phenomenon of cold flow may be having an influence on this problem. It is a fact that plastics, especially molded thermoplastics, when put under long term compression or tension, can relax, creep, or "cold flow". This means that a sleeve that is pressed onto the shaft at the factory may seem impossible to budge but after a couple of years of use and the high temperatures that the shaft sees may cause the sleeve to become loose enought to start slipping. In this scenario, the more you use the compressor and the higher the the ambient temperature, the sooner the problem will surface. If I am right about this then the secondary problem of the actuator slipping on the shaft may also occur, and would mimic the problem of refusing to start. I see temps above 100 degrees in my garage most of the summer here in Tucson so I am probably experiencing the problem sooner than someone in Minneapolis.
The bottom line here is that we as owners of this fine Crafstman compressor have a fundamental product reliability problem. If you purchased the extended warranty and it is about to expire, then you may want to contact S-e-a-r-s to express your concern about this issue. They MUST know about it by now. Although it is possible to do the quick remedy of sliding the actuator back into position, this may turn out to be a progressive problem and may require more frequent attention if my theory of cold flow holds up. The motor manufacturer has complicated things by using the retaining washer. They are almost impossible to remove without ruining them, and without marring the shaft. A better fix would involve marking the proper location of the actuator on the shaft, removing the retaining washer, completely removing the actuator, roughing up the shaft where the actuator sits, solvent cleaning the shaft and actuator, and installing the actuator on the shaft with a suitable bonding adhesive. The retaining washer would no longer be needed, since it did no good in the first place other than to give us a reference for where the actuator should be.
I hope this all helps.
Steve
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Member Since
11/05/2004
Total Contributions
10 Posts
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Moderated by Handyman 
