Air Compressor Problems

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PostPosted: Wed Jun 29, 2022 3:30 pm
I pulled the capacitors and the run capacitor has some issues for sure:
Air compressor run capacitor damage.JPG


Then I found this small hole in the aluminum tubing running from the Pressure Switch to the tank Check Valve:
Hole in tubing for Air compressor.JPG


The tank check valve has seen better days as well:
Air Compressor Tank check valve.JPG


Ordered new capacitors and check valve today. Hoping the local hardware has the 1/4" aluminum tubing I need.
1968 Coronet R/T


ACTS 16:31

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PostPosted: Thu Jun 30, 2022 11:52 am
Coronet,

After you get the parts replaced, hopefully it works and your problem is solved.

If the breaker is still tripping however, I would use a logical process of elimination to determine if it's the Breaker, the Motor, or something with the Pump.

Reasons why the Breakers Trip:

1. If you have an inter-mitten short circuit somewhere, the current will spike which will cause the breaker to trip.

2. If the motor cannot get up to speed (because something is wrong with the pump or motor) the current will go up, which will trip the breaker. A problem with the pump or a bad bearing in the motor can cause the motor's armature to slow down, resulting in the current going up which trips the breaker.

3. You could also have a bad breaker.

Trouble Shooting:

First I'd put an amp meter on the wire feeding the motor and turn the compressor on to see how many Amps your motor is pulling. It should pull close to what the FLA rating is on the motor's data tag. Watch to see what the current does right before it trips.

If the pump is slowing the motor down, the current will go up above the normal Full Load Amps (FLA) and cause the breaker to trip. If you remove the belts so no pump is involved, and then start the compressor, the motor should get up to full speed and the current should stabilize near the FLA rating of the motor. Watch and see if it still trips.

If you do the above, and the break doesn't trip you've confirmed the issue is in the pumping system. If it still trips, the problem would be in the motor or the breaker.

Hope that helps in isolating the problem ~ Lenny B



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PostPosted: Fri Jul 01, 2022 3:09 pm
Rather than replacing tubing with Aluminum I would use Copper schedule 80 much stronger than Alum. and Its what should be used, Hi heat, water bad combo for Aluminum.

That Run Cap defiantly looks like its seen better days, Looks Like the Magic smoke came out.
Do you have a Good multi meter? You want one that will measure Capacitance to check that Start cap out Or replace it your choice.

https://www.youtube.com/watch?v=H792xf78loU
Dennis B.
A&P Mechanic, FCC General radio Telephone Operator
Line Maintenance A&P Mechanic and MOC Tech specialist.

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PostPosted: Fri Jul 01, 2022 4:50 pm
Doright wrote: I would use Copper


Agree. Although I've the plastic with the push-in fittings and that works ok too.

Doright wrote:Looks Like the Magic smoke came out.


Yep.
Chris

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PostPosted: Fri Jul 01, 2022 5:44 pm
Doright wrote:Rather than replacing tubing with Aluminum I would use Copper schedule 80 much stronger than Alum. and Its what should be used, Hi heat, water bad combo for Aluminum.

That Run Cap defiantly looks like its seen better days, Looks Like the Magic smoke came out.
Do you have a Good multi meter? You want one that will measure Capacitance to check that Start cap out Or replace it your choice.

https://www.youtube.com/watch?v=H792xf78loU


I order new capacitors, pressure switch and tank check valve. Figured it wasn't worth messing with 15 year old parts. Hoping the pump is okay, since I changed the oil regularly and air filter as well.
1968 Coronet R/T


ACTS 16:31



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PostPosted: Fri Jul 01, 2022 6:45 pm
'68 Coronet R/T wrote:
Doright wrote:Rather than replacing tubing with Aluminum I would use Copper schedule 80 much stronger than Alum. and Its what should be used, Hi heat, water bad combo for Aluminum.

That Run Cap defiantly looks like its seen better days, Looks Like the Magic smoke came out.
Do you have a Good multi meter? You want one that will measure Capacitance to check that Start cap out Or replace it your choice.

https://www.youtube.com/watch?v=H792xf78loU


I order new capacitors, pressure switch and tank check valve. Figured it wasn't worth messing with 15 year old parts. Hoping the pump is okay, since I changed the oil regularly and air filter as well.


I am sure your Pump is fine unless it was making oil in the main line?
BUT
What kind of Valve system does your Pump have? Their are few different designs but good maintenance includes cleaning and inspection of the valves and springs.

My current pump has Reed valves that are subject to over heating and breaking if the pump is run continuously for long periods of time without a break over heating them that can reduce air output significantly.
I plan to do a Top end overhaul of my Pump soon replacing the Reed valves with new ones just because I don't know for sure how many hours are on the pump itself for sure.
It was or looked new when I got it but that doesnt mean anything I am gonna do it so I know for sure. I am also planning a whole new motor and a Bigger custom ordered air tank with internal coating.

The Valves I had in other Pumps over the decades most all had the cheap floating disk style valves with a spring here again the springs are subject to over heating and breaking and the valves and seats were subject to burning oil and fouling the seal between the two a quick cleaning with a good solvent most always cured sealing problems but have had a few were I had to do a quick lapping of the Valves with 600-800 grit & WD40 on a piece of flat glass to get things flat again only ever found one broken spring have seen others with Reed style valves that were broken as mentioned above.
As I said above their are Many many different designs for Air compressor pumps.
Seek out your Manufactures Parts assembly manual and order parts as required IF available!
Dennis B.
A&P Mechanic, FCC General radio Telephone Operator
Line Maintenance A&P Mechanic and MOC Tech specialist.

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PostPosted: Sat Jul 09, 2022 7:33 pm
Success.

$194.97 in parts and my compressor is up and running again.

Need to adjust the pressure regulator a bit, since it kicked off at 180 psi instead of 175 psi but other than that it sounds great. :happy:
1968 Coronet R/T


ACTS 16:31

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PostPosted: Sat Jul 09, 2022 9:38 pm
Always feels good to get "old faithful" up and running again, right? :)
Metal, wood, fiberglass, we work it all... www.furniturephysicians.com We can restore the irreplaceable!

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PostPosted: Sun Jul 10, 2022 6:12 am
Says a lot for the toughness of that machine - that it took ALL of those problems to actually stop it.
Chris

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PostPosted: Sun Jul 10, 2022 3:42 pm
NFT5 wrote:Says a lot for the toughness of that machine - that it took ALL of those problems to actually stop it.


My guess is the Run Capacitor and the Tank Check Valve were the main culprits.
Rather than risk another shut down, I decided to replace the other parts as well.
1968 Coronet R/T


ACTS 16:31
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