A Different Compressor Question

[J T]

My older son's boss gave him a large upright air compressor, because the compressor was "locked up". The boss preferred buying a new air compressor, rather than messing with the old one. The motor, 220, works fine. He hasn't gotten a 220 line to his shed yet, so won't get to looking inside the compressor for awhile.

Thing is, he's discovrred the compressor isn't "locked up", as he was originally tols. He can move the pulley on the copressor about a quarter turn each way, then it stops. So, I'm wondering if anyone here has run across a similar problem, and what the cause was. If it may be something he may be able to fix on his own, without buying a new compressor, or if the compressor just may need a rebuild, or it totally toasted, and needs to be replace in it's entirity.

I know hell find this all out when he is finally able to get to it, but I'm just curious.

JOAT You only need two tools: WD-40, and duct tape. If it doesn't move and it should, use WD-40. If it moves and shouldn't, use the tape.

[pemerson2]

After the compressor shuts off there is a valve that opens that relieves the pressure from the piston. If that valve does not open the next time the compressor starts it will not turn because the motor cannot start under a load. These valves are usually external, and can be serviced without disassembling everything.

[Mike Marlow]

If the compressor was run very low on oil JOAT, it will seize up, but once it cools down it will often move again. The rings will be toast and the compressor head output will be reduced, but it will still work. Usually if this is the case, you can rotate the pulley more than what you're describing above though. If it's binding up hard, I'd suspect more severe damage inside the head. But... the price was certainly right, so likely it will be worth his effort to tear the head apart and rebuild it. What make and model is the compressor?

[DanG]

You should be able to turn the flywheel by hand even if there is a full charge of air in the tank. It would be quite a system to still have a full charge of air after being moved.

Remove the belt, assuming it is a belt drive. See if the electric motor is working fine - I expect that it is.

Try again to turn the compressor pulley, I suspect it will still be jammed. The next step is to disassemble the compressor head. This is no big stunt if you have ever been this far on an auto engine. Most of the parts are quite similar other than the reed plate. Diagnose and decide what to do once you see the condition of the jugs, reeds, crank, rings, rods, and rod bearings. It may be simple and cheap . . . but don't hold your breath.

Let us know what it turns out to be.

(top posted for your convenience) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Keep the whole world singing . . . . DanG (remove the sevens) [e-mail]

[Leon]

Well if they thought it was locked up, it sounds to me like the rings may have broken and are how hitting the ridge in the cylinder that has formed from wear. It really could be a number of things. I would say that it is related to the piston, connecting rod or crank shaft. I would pull the head and see what is going on when you turn the pulley.

[Leon]

Good thought but in this instance I would venture to guess that there is no pressure in the tank and this would not apply and turning by hand under a load the pulley would probably not stop 1/4 turn in either direction and then stop.

[W Canaday]

I want to thank you for your thoughtful response to my question regarding gluing up a segmented cane for an elderly friend who will also be relying on it for his defense. Your suggestion that I use something called "wood glue" showed a lot of thought and obviously drew upon your vast wells of experience. I can't tell you how much I appreciated it.

This is -my- response to -your- question.

BTW, I repair small machinery, including compressors, for a living.

Bill

[J T]

Thanks guys. This'll be sort of a generaci response.

I never thought to write down the make. The compressor itself didn't have any name one it I could see. It looked pretty much like any other two-cylinder compressor anyway. The air tank is empty. The belt is loose. No grating noise evident when the pully was rocked back and forth. It'll probably be awhile until the kid has time to look inside of it - he warks hard, and some long hours, usually 6 days a week. Apparently they checked the motor at work, so he says it's good. This is just the type of info I was after - general ideas of what could be wrong - so I can pas it all along to him. That'll give him a starting point. And, if worse comes to worse, he's prepared to get a replacement compressor for it.

Like I tell my kids, accept almost "anything" someone offers you for free. Then if it turns out you can't make it work, or don't want/need it, you can always: Make something out of it, sell it, trade it, give it away, or just trashe it. For now the kid is using this as an air tank, hooked up to his HF gas-powered air compressor for sand blasting. Works out quite well.

JOAT You only need two tools: WD-40, and duct tape. If it doesn't move and it should, use WD-40. If it moves and shouldn't, use the tape.

[J T]

Sun, Jan 29, 2006, 12:57pm [e-mail] (W=A0Canaday) now sayeth: segmented cane for an elderly friend who will also be relying on it for his defense. Your suggestion that I use something called "wood glue" showed a lot of thought and obviously drew upon your vast wells of experience. I can't tell you how much I appreciated it.

Defense, eh? Don't recall a prior mention of defense. I'm not exactly a kid anymore, so I use a cane myself. It's certainly sturdy enough for defense - IF I were properly trained in its use for defense, "and" more agile that is. As is, I do have a theoretical knowledge of stick fighting; however, I'd "still" probably wind up getting it taken away, and then get beaten with it - unless I was very fortunate. I certainly would NOT want to rely on it as a primary means of defense, not as long as there are better alternatives anyway.

A silly questions always deserves a silly response. Were I to glue up a segmented cane, for defense or not, I'd use wood glue. Titebond II to be specific, it's my woodworking glue of choice. It's stronger than the wood, so I have no doubt it would suffice. Thanks for sharing your wealh of compressor information. You have a nice next life.

JOAT You only need two tools: WD-40, and duct tape. If it doesn't move and it should, use WD-40. If it moves and shouldn't, use the tape.

[Ba r r y]

FWIW, several others also suggested wood glue, and probably a hundred more of us declined to answer because the question was already answered.

Brand name is irrelevant. If you ask for "wood glue" in any hardware store, they'll hand you what most of the respondents suggested.

[Pat Barber]