Do bi-metal relays wear out?

FYI, you can get a variable speed 3 phase 230VAC gear motor (1/15-1/6 Hp) for around $100, typically these have a speed range of 10-110Hs or similar. One below is 19 RPM, so should be good for around 5-35 RPM it has a 1/2" output shaft. There are also a ton of Oriental gear motors, but will have to deal with metric shaft sizes and chinglish instructions.

Lots of inexpensive VFDs, anywhere from $60-130, there are also some dumb types from KB Electronics (KBVF series, KBVF-21D, 22D, 23D) that I have used with no programming, just connect and set the jumpers and some trim pots.

 
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I've got a relay on my parts washer and it's just started tripping. Runs for about 3 minutes them trips, comes back on in about a minute and runs for a couple then trips again.
In a word, yes, but. . . The "relay" is actually an "overload" protection device. It is there to protect the electrical parts connected to it. While it can fail, it isn't very likely. Having read the posts, most of them are on point, but. . . The electrical world is overflowing with "buts", that's the nature of the field.

With small gear motors, many times there is one, or more, phenolic gear. That is the most likely source of trouble. Finding another will be a bear. Quite likely, the motor was damaged when it got into a "locked rotor" situation. it may be less expensive to just replace the motor. Something as simple as a microwave oven turntable motor would suit, if it could be waterproofed. There are many sources for such motors. But you will need to adapt the mounting. Three phase conversion is an option, but not recommended. It over-complicates the whole machine.
 
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