my 70yo problem (air compressor)

[grvtman]

my grandfather bought this air compressor in the 40's. i finally acquired it from my dad. had a bad check, was the original one, so i changed it. now it is still leaking air when the the pump is running. in the first pic the air is coming right under the big nut. the second pic is from the side and you can see the part hanging down where the air is coming from. i have no clue about air compressors, be it part names for anything else. but i do know motors and can do most things myself. any help would be great. also if anyone knows anything about the pump please inform me would like to know. the only think that has been changed is the motor it was replaced in the 70's. thanks for reading

 

[Outlawmws]

my grandfather bought this air compressor in the 40's. i finally acquired it from my dad. had a bad check, was the original one, so i changed it. now it is still leaking air when the the pump is running. in the first pic the air is coming right under the big nut. the second pic is from the side and you can see the part hanging down where the air is coming from. i have no clue about air compressors, be it part names for anything else. but i do know motors and can do most things myself. any help would be great. also if anyone knows anything about the pump please inform me would like to know. the only think that has been changed is the motor it was replaced in the 70's. thanks for reading

Get some colored arrows into the pics, as I have no idea what "big nut" you are talking about.

 

[kams1973]

I believe you are referring to the centrifugal compresson release. It's function is to release any compressed air between the compressor outlet and the tank check valve when the pump is not running. This allows for easier start ups. I am not familiar with Champions, but I'm sure it's a simple shrader style valve. Think valve core on a tire. Take it apart and clean it up. It may simply be some trash under the valve seat.

 

[RECox286]

A finger pointing to the problem child would work as well.

Uncle Bob

 

[jabberwoki]

That's a sweet old compressor i hope you get it sorted out

 

[grvtman]

sorry here is a pic with 2 arrows 1 for the big nut and the second for where air is coming from while pump is running. and i think kams1973 is right about it. i did remove the nut and cleaned it out but not sure i put it back together right. is it ball then spring or spring then ball. had my son open it and he drop everything when he did. and thanks all for the quick replies

 

[kams1973]

I'm not familiar with the unloader champion used/uses. However, if all else fails, simply buy a new pressure switch with a built in unloader. Disconnect the line going to the unloader on the pump and plumb it to the unloader on the pressure switch. I had to do this with an old United States Air Compressor and it worked like a champ.

 

[Charles (in GA)]

I'm not familiar with the unloader champion used/uses. However, if all else fails, simply buy a new pressure switch with a built in unloader. Disconnect the line going to the unloader on the pump and plumb it to the unloader on the pressure switch. I had to do this with an old United States Air Compressor and it worked like a champ.

Indeed, that is the centrifugal unloader. Some flyweights inside there open the valve when the compressor is stopped, and when it starts up, the weights swing to a different position and allow the valve to close, which is apparently not happening.

The above suggested fix will work, or you probably can get a breakdown drawing from Champion and tear it apart. It may be worn out, or it may just be sticking.

Charles

 

[1948]

i would have someone who knows what they are doing rebuild it for you......

 

[bad_idea]

Get a teardown manual for it and try to repair the existing unloader. That pump is way too cool to "modernize" it with a pressure switch with built in unloader.

 

[jrsulo]

Replacing the unloader on my 1959 curtis as it was missing alot of parts,with one that works off a pressure switch....hated to do it but parts were not available.....also pulled the check valve to replace,and there was no check valve !!!!....no wonder it wouldent pump past 45 psi,and would bog down !!

 

[grvtman]

I took the nut off and cleaned the spring and ball inside. I seen a pic of how it goes together and put it back to how it should be. Still having a leak. I then opened the housing and cleaned in there. Im thinking the problem should be in the ball spring or the pin. Or just under the flyweight is the plate that pushes the pin. It has a small indent like it is warn so that may also be the culprit. I'm guessing the pump is a r15b but I could be wrong. I'm wanting to stay original with it. And as for a pro rebuild I think I should be able to do it myself so that would be a last resort. Thanks all for the replies

 

[1948]

maybe it had a asbestos, or cotton rope seal that the ball pressed onto?

are you sure its not supposed to just leak crankcase pressure out of there at that time? or are you saying that when its off, and while it sits with pressure, the tank pressure leaks back through the pump? if so then you have a totally different issue altogether.

 

[1948]

this guy might know

 

[Zrexxer]

If these models leak while the compressor is off, it's the check valve bleeding back, if it leaks while the compressor's running the unloader isn't closing properly. SO whatever is actually causing it, it's almost certainly the unloader valve causing the problem.

And by the way, the fitting where you have the yellow arrow is where the unloader discharges normally, so there is supposed to be air coming from there, but only for a couple of seconds after the compressor cycles off.

 

[grvtman]

This is happening when it is running and it's not a little it's quite a bit. Had it running about 15 years ago and it didn't leak when running. After sitting for 15 years now it leaks. Been through it and cleaned but still leaking

 

[1948]

try putting some oil in the cylinders and see if it helps at all, im wondering if the rings are froze

 

[edboyles]

I believe these models have a "vent" in addition to the centrifugal release to release the internal pressure from the crankcase from the rings, etc while running. If it is excessive then you have leaking valves/worn rings allowing too much air in the crankcase.

 

[grvtman]

Would like to thank everyone on there input. I did what 1948 said and put some oil in the cylinders and everything is working great. Now to get it all cleaned up and some new paint and belts. Thanks again all I'll post some pics o it when I'm done with it

 

[1948]

its most likely splash oiled, so it needs to be filled with oil in the crank case(might be a dipstick might need to jut fill to the cap.( if it isnt already.) good to hear you got it going.

 

[grvtman]

well got it cleaned up and painted. used rustoleum hammered silver, rolled and brushed. going to trim it out in red and need to finish putting it together. then will wire it and plum it in. still need to find some valves for it. not the greatest pictures of it but here they are

 

[Crazy68Dart]

Very cool. I usually try to hide my compressor, but not in this case!

I know this is not the point, but what is the CFM rating on something like this?

 

[Bob C]

Very cool. I usually try to hide my compressor, but not in this case!

I know this is not the point, but what is the CFM rating on something like this?

Old units usually turned low rpm. My guess ... 14.8 at 90 psi.

 

[jamesemery728]

Make sure you clean those pipes with the flutes on them. The flutes are there to dissipate the heat away from the pipes.

 

[Bob C]

Make sure you clean those pipes with the flutes on them. The flutes are there to dissipate the heat away from the pipes.

Those pipes are called an "Intercooler"

 

[grvtman]

I cleaned them just need to straighten the fins. Not sure what the Cfm is on it but it's about 100 psi when I checked last( about 15 years ago or so)

 

[DekeT]

I cleaned them just need to straighten the fins. Not sure what the Cfm is on it but it's about 100 psi when I checked last( about 15 years ago or so)

That is a very fine looking machine. Kudos for keeping the history alive.

An approximate cfm can be calculated with some basic measurements of fill time. I would be curious what that old machine will do.