Kellog American 0331 air compressor

[akadeutsch]

I have an old Kellog American compressor # 331 that has been around since the later 1950s. My father left it to me when he passed and now it is in my garage. I have replaced the 5 horse motor with a new 5 horse "Leeson" unit and rebuilt the pump using new rings, new bearings, and new gaskets. My problem is that I keep throwing rod bearings. It sounds like a damn tractor running. Could this be caused by an out of balance fly wheel? Someone has done some welding to this thing and it does not look balanced...of course I can not tell by just looking at it. What do you think? Also if anyone has any specs on this pump I would love the info. Like oil capacity. How much oil should I put in this thing?

 

[yaidunno]

Nice compressor.

There's a few things that really throw me for a loop in your post. First, if you don't know how much oil to put in it, why are you running it? If there isnt enough oil in a splash lubricated pump, its going to seize the bearings. For reference, my Champion compressor of the same size takes 2 quarts of lube.

What do you mean by "throw a rod bearing"?

Also, the belts don't look to have enough tension. And whats with the wood mounting?

 

[larry_g]

When you put the bearings in it did you mic the crank and make sure that it is to size and that it is round? If splash lubricated are all the dippers and channels in the correct position? Do you know what the bearing clearances are supposed to be and what they really are? Rebuilding a pump like that is just like rebuilding an engine and requires the same care and precision.

lg
no neat sig line

 

[CJinPA]

I just rebuilt a 331 pump. Did you properly set the preload on the tapered bearings? Did you replace the races when you replaced the bearings. Did you get the oil slinger ring installed right? Those are just a couple areas where I could see an issue.

 

[akadeutsch]

Thanks guys. I'll drain the oil and measure what I had in it now. I think I had at least two quarts. There is a sight glass but the crank wont even touch the oil if I fill it half way up that. I did make sure that the crank is hitting the oil. The bearing that went out last time was the low stage pin bearing. And it sounds like the same thing this time. My machine shop put the pistons together for me so I guess I trusted them to check the clearance. I was not sure on the belt tension so I will tighten it up a bit. The wood mount was my only option as I do not yet own a welder to fab a plate. I could not get the fly wheel off so I did not remove the crank but there was little play there so I was not worried. Back to my question...Could an imbalanced flywheel cause the low stage pin bearing to go out?

 

[yaidunno]

Thanks guys. I'll drain the oil and measure what I had in it now. I think I had at least two quarts. There is a sight glass but the crank wont even touch the oil if I fill it half way up that. I did make sure that the crank is hitting the oil. The bearing that went out last time was the low stage pin bearing. And it sounds like the same thing this time. My machine shop put the pistons together for me so I guess I trusted them to check the clearance. I was not sure on the belt tension so I will tighten it up a bit. The wood mount was my only option as I do not yet own a welder to fab a plate. I could not get the fly wheel off so I did not remove the crank but there was little play there so I was not worried. Back to my question...Could an imbalanced flywheel cause the low stage pin bearing to go out?

I suppose anything is possible, but i would think that you'd have a lot of other noises if your crankshaft was flexing. How have you determined that the flywheel is out of balance? I'd have to assume that it doesn't run true after it was welded?

 

[stage20]

I've got a 331 and run 3qts. I think the spec is shy of that. With a screwdriver down the fill hole its probbly 2" from the bottom which just overs the sight glass. Cant see in mine. Its cloudy.

 

[zkling]

LOL at your intake that is bitchin'. Highly doubtful that an imbalanced flywheel is causing issues with the con rod bearings. If you were killing crank bearings that would be a different story. Does the con rod have an oil slinger of some sort? Sounds like either an assembly problem or lack of lube, or both. What do the worn parts looks like? You are running a proper RPM for the pump right?

You may also want to check the crank shaft for straightness. And the rod journals for circularity.

 

[kams1973]

There's an oil ring on the crankshaft. This is not a splash lube design; it is a positive ring fed lubrication type. If you are burning up rod bearings, you need to disassemble the pump and check the oil passages in the crankshaft. You may have a blockage.

 

[zkling]

There's an oil ring on the crankshaft. This is not a splash lube design; it is a positive ring fed lubrication type. If you are burning up rod bearings, you need to disassemble the pump and check the oil passages in the crankshaft. You may have a blockage.

Ah, woops I wasn't sure on that one. Guess I should have done a bit of research before opening my mouth.

 

[Fixnair]

You might want to check your interstage pressure. Your 1st stage piston (the large one) should see 35-40 PSI. If your high pressure valves are not working then the interstage pressure will be high. Could be as high as final discharge pressure.
You can see that the low pressure piston has a large area. Many square inches. This piston should see 40 PSI max. If you multiply the square inch area of the piston times 40 PSI then you get the bearing load allowed on that wrist pin and insert. Now if your second stage is not working and the first stage is doing all the work (pumping up to 120 PSI) you can see your bearing load is going to be three times what it should be.
I think kams1973 is right on with his diagnosis. It is easy to check your interstage pressure though. You need to find a way to install a pressure gauge on the inter cooler tubes. The two that run behind the flywheel. There is usually a pipe plug or safety valve in the head. Put your gauge there.
An out of balance flywheel will not cause your bearings to destroy themselves. That us not the problem.
Let us know what you find.

 

[C96]

I am going to give you the benefit of the doubt that the rotation is correct

 

[akadeutsch]

There is an arrow on the flywheel showing proper direction of spin. RMPs = 1740...right in spec. I never rebuilt the head so I would like to measure the inter-stage pressure. This will be my next step. Any advice on this process would be great. I was running 2.5 quarts of oil so I doubt there was a lack of lube issue. But I added another half a quart just to be safe. thanks stage20. I'll let you know what I find I just hope it's not $$$ because all of my extra money is going into the jeep right now. Im building a jeep 4.6 stroker for my 2000 WJ.

Thanks for all of the advice

 

[akadeutsch]

There's an oil ring on the crankshaft. This is not a splash lube design; it is a positive ring fed lubrication type. If you are burning up rod bearings, you need to disassemble the pump and check the oil passages in the crankshaft. You may have a blockage.

Not main rod bearings I'm having a problem with, but the wrist pin bearing that holds the piston to the con rod. This and the fact that I never removed the crank lead me to believe the problem is in the top end. I'll check inter-stage pressure.

 

[b-body-bob]

There is an arrow on the flywheel showing proper direction of spin. RMPs = 1740...right in spec.

The flywheel arrow is only accurate until someone takes the flywheel off and reinstalls it backward.

Also, 1740 is the motor RPM, which will be OK if the factory pulley/flywheel is still in place. The ones in the photo look original, but if different ones are installed the diameter could be different, changing the pump RPM. You can measure the pulleys, do some math, and confirm the actual pump RPM.

 

[akadeutsch]

what happens if it is spinning the wrong way? anyone out there tell me which way it is supposed to spin?

 

[stage20]

The flywheel has a dish to it I believe. Have to lok at mine. It may go on both ways but only looks right one way.

 

[bsaint]

what happens if it is spinning the wrong way? anyone out there tell me which way it is supposed to spin?

The pump will not cool correctly. It suppose to spin with the air drawing from the front to the back. The face of the flywheel back.

I notice in the picture your compressors is opposite of the normal (flywheel near the wall.)

For reference the front on the compressor pump is the same as the front of the motor. Flywheel (pulley) side.

 

[akadeutsch]

I am still unclear as to which way this thing should spin. should it blow air over the pump? or **** air past the pump? This is a picture of why I think it is out of balance. It is obvious to me while writing this that my next move should be to buy a new flywheel. And perhaps a complete overhaul kit...to include the top end. I would be shocked if it worked as well as it has been working if it were spinning the wrong way. But anything is possible, at least that would be easy to fix. Problem is that I still need to CC my cylinder head combustion chambers for my jeep build and I will need to use it while I complete that work. I will update again when I am able to buy a new flywheel. Where can I get parts for a 331 TV pump?

 

[bsaint]

I am still unclear as to which way this thing should spin. should it blow air over the pump? or **** air past the pump? This is a picture of why I think it is out of balance. It is obvious to me while writing this that my next move should be to buy a new flywheel. And perhaps a complete overhaul kit...to include the top end. I would be shocked if it worked as well as it has been working if it were spinning the wrong way. But anything is possible, at least that would be easy to fix. Problem is that I still need to CC my cylinder head combustion chambers for my jeep build and I will need to use it while I complete that work. I will update again when I am able to buy a new flywheel. Where can I get parts for a 331 TV pump?

It should spin so its drawing air from the face of the flywheel to the back cylinder.

 

[zkling]

I am still unclear as to which way this thing should spin. should it blow air over the pump? or **** air past the pump? This is a picture of why I think it is out of balance. It is obvious to me while writing this that my next move should be to buy a new flywheel. And perhaps a complete overhaul kit...to include the top end. I would be shocked if it worked as well as it has been working if it were spinning the wrong way. But anything is possible, at least that would be easy to fix. Problem is that I still need to CC my cylinder head combustion chambers for my jeep build and I will need to use it while I complete that work. I will update again when I am able to buy a new flywheel. Where can I get parts for a 331 TV pump?

In that picture it should spin counter clock wise. Does the pulley have axial runout at the peremiter? Brace a solid object on the block a very short distance from the face of the pulley edge and see if there is a wobble as you turn it over.

 

[akadeutsch]

yes it does. it has a little wobble.

 

[kams1973]

I may be mistaken, but if this is a positive ring fed lubricated unit, the oil for the wrist pin comes from a hole bored through the length of the conrod.

 

[zkling]

yes it does. it has a little wobble.

How much is a little wobble? Few thousands, 1/4"? I think you may have other major problems on hand.

 

[akadeutsch]

probably close to a 1/4 inch of wobble. It is spinning faster now that i tightened the belt and it sounds great till it gets to about 40 psi then it starts to knock.
The Conrod is solid. There is a brass tube that runs the length of the con rod, and they were clean and clear when I put it together. I would be shocked if that tube was clogged now. Im still leaning toward a sticky valve in the head causing interstage pressure to be too high. problem is I have nothing but a compression gauge to test it. Any one have an idea of what tool to use?

 

[larry_g]

http://www.aircompeq.com/ka.htm

Above is a link to some specs. Maybe call them for parts.

lg
no neat sigline

 

[Fixnair]

Looking at your pictures the rotation should be counter clockwise. If you happen yo turn it backwards it will still pump and lubricate alright but the centrifugal flyweights will unscrew. They are located inside the crankcase on the opposite end as the fly wheel.

 

[akadeutsch]

Aw... I see. It is however turning the right way. Now I am just concerned about the run out in the flywheel. Could that just be due to imbalance?

 

[mayday0017]

Just want to throw it out there, if the flywheel has any slack in it and is not clamped down very tight to the crank you will have what sounds like rod knock that isn't rod knock. So make sure there is zero play in the flywheel on the crank shaft.

 

[akadeutsch]

Thanks...the flywheel is so seized to the crank that I've broken two pullers trying to get it off. I doubt it is moving. Ill index it and run it a little to see if it moves. good idea!