Air Compressor Help

[Tinkerman]

I know that this is not really a Triumph problem and I beg your indulgence this time. My wife's best friend lost her husband about two years ago and I have become her "go to guy" for electrical and mechanical problems. About a year ago she bought a very small pancake air compressor, 115 PSI max,110v, 2.4 cfm. She uses it to air up lawn mower tires and similar lightr duty stuff.
It quit putting out air pressure. It still runs and sounds like the pistons are working but no output. Anyone have any ideas, other than using it as a boat anchor?

Thanks for any help on this one, Tinkerman

 

[DougF]

If there is no evidence of air leaks, my guess is boat anchor. You will have to add weight since it will probably float.
Contact Tinster. He may be able to use it as a bobber.

 

[TR3driver]

No idea what the most likely problem is, but it shouldn't be too hard to troubleshoot. Pull it apart and see what doesn't work. If it's not a leak and it sounds fairly normal, my first guess would be unloader valve stuck open, or maybe one of the reed valves.

Of course, it may still be junk, but can't hurt to look.

 

[hilsideser]

DougF, you're bad....

Patrick

79' driver
79' next driver
78'
77'
80' project

Waynesville, N.C.

 

[PlaidMan]

The copper pipe attached to the head is either cracked or the plastic seal on the end of the copper pipe is leaking , (Oil less compressors only). Take the compressor cover off and turn it on, feel along the copper pipe close to the connection by the head and you will probably feel air coming out, but don't wait too long as that pipe will get very hot.

 

[Tomster]

Is there a drain on the bottom of the tank that could be open?

 

[Tinkerman]

Drain is closed. Compressor is working fine but the air is not getting to the tank. Gotta be the pressure switch. She only paid $30 for the unit. Probably time for a new/better one. Suspect the pressure switch is going to cost more than she paid for the unit!

Thanks for your input, gotta love the BCF!

Regards, Tinkerman

 

[dklawson]

Even on the diaphragm pumps... are there not reed valves? I've seen those fail in piston type pumps after long periods of operation.

Piston pumps also have an unloader valve that makes it possible for the motor to start the whole thing turning. If the unloader is stuck open the pump won't build up any pressure.

I haven't worked on a diaphragm pump so the above may not be useful. I agree with TR3 Driver... start taking it apart and see what you find.

 

[Guest]

Tink, Home Depot sells a really good quality air compressor (All American made, yet!) for WAY under 300 bucks that is on wheels and stands vertically. 26 gal unit. I labored with an old dental compressor for years until I finally had it hauled off. Old compressors aren't worth repairing, period.

 

[dklawson]

Old compressors aren't worth repairing, period.

I bought my compressor used from my neighbor... 19 years ago when it was about 19 years old. I've replaced some of its plumbing and its valves. Over my nearly 20 years with the thing I've invested a total (purchase and maintenance) of about $100. It's a 2-Hp Craftsman unit with a cast iron 2-cylinder pump. My point... in many instances it does pay to maintain and/or repair a compressor, even old ones.

Perhaps Tinkerman's friend doesn't need or want a $300 compressor.

 

[Tinkerman]

She is beginning to realize that cheap isn't always good! We did find a web site yesterday evening for the distributer so she is going to call them Monday. And no she doesn't need one that expensive. There are quite a few good ones out there for under $100.

Thanks for all your help, Tinkerman

 

[dklawson]

Did you determine what part had failed?

 

[Tinkerman]

Did you determine what part had failed?

By the process of elimanation, the pressure switch. I have not taken it apart though, so maybe tomorrow I'll see what I can find that might be wrong.

Tinkerman

 

[dklawson]

It's ccrious if it is the switch. The job of the switch is to call for the motor to run and tell it when to stop.

Some switches also incorporate the unloader valve which makes it possible for the motor to start in the first place. It could be the unloader valve portion of the valve is stuck "open" since in your initial post you report that the compressor still sounds like it runs but that it won't build pressure.

 

[kc_doyle]

I was given a compresser by a friend. He hadn't used it in a while because it needed a new motor. I replaced the motor and plugged it in and it worked great......till the tank blew up and just missed me and did over $2000.oo damage to my car and blew out a section of my garage wall. Hmmmm go figure.

 

[Tinkerman]

wow thats scarey. I had never heard of that type of problem. Did the pressure switch malfunction, must have to build up that kind of pressure.

Glad it missed you, Tinkerman

 

[kc_doyle]

It had to be the pressure switch hanging up, but who was to know. It came so close as to put a 6 inch rip in the leg of my wranglers but didn't even scratch the skin. The concussion knocked me right on my butt.

 

[TR3driver]

I had a similar problem with my air compressor, except I now think the unloader valve opened and limited how high the pressure built. The pressure switch contacts apparently welded, and the pressure relief valve was apparently stuck or full of dirt.

I had flipped on the compressor while I did some other work, but noticed it hadn't shut off and was smelling hot. When I went over to investigage, the pressure gauge was pegged ! Touched the relief valve and it spit out a chunk of something, then screamed for a full minute.

You're supposed to test the relief valve occasionally to see if it's clear ... from now on, mine is going to get tested !

However, air tanks don't last forever, and generally fail by rusting from the inside out. Any time one has sat around for a long time, it is suspect, IMO. 100 psi times the surface area of the tank is a whole lotta force ...

 

[Tinkerman]

Ok, dumb question #1027. How do you operate the relief valve? After all of my fooling around with compressors you'd think I would know but I don't! Never tested one!

Tinkerman

 

[TR3driver]

Depends on the valve design. Some have a lever you lift, mine has a ring to pull.