Have a dewalt Dxcm601 60gal compressor. It was bought at tractor supply for a really good deal. Issue I have run into is two fold. First it takes about 12min to fill up till shutoff. It’s an 11cfm at 90. Second today I noticed when it got hot from running there was a whiteish smoke coming from near the flywheel pulley of the pump. It has no odor other than hot any ideas what to look for. Thanks
Compressor questions
- Thread starter Fball1208
- Start date
B_Bimmer
Well-known member
Any chance you have a leak before the check valve, possible near the head, that would leak only when running, hence releasing high moisture air up there and causing your compressor to take longer than normal to fill?
redmondjp
Well-known member
Is the crankcase vent near the top of the bearing on the back of the pump, by any chance?
Based on my compressor calculator it should take about 8 minutes to fill (I'm assuming you aren't living in Denver or some other high altitude location).
The smoke could be a slipping belt. I recently was dealing with a slipping belt on my compressor. Didn't catch it in time and ended up burning the belt a bit. After that it would slip. I guess after 20 years it's OK to change it.
Why was the flywheel replaced? Is it the same size as the old one? Are you certain the belt isn't slipping? Mine made no belt noise when slipping (it wasn't new) but the pump seemed to bog down and filling was slow.
Another thing to check is the unloader valve. In many compressors you have a tube going from the tank check valve to the pressure switch. If that is leaking then some of your air is going to leak out by the pressure switch.
The smoke could be a slipping belt. I recently was dealing with a slipping belt on my compressor. Didn't catch it in time and ended up burning the belt a bit. After that it would slip. I guess after 20 years it's OK to change it.
Why was the flywheel replaced? Is it the same size as the old one? Are you certain the belt isn't slipping? Mine made no belt noise when slipping (it wasn't new) but the pump seemed to bog down and filling was slow.
Another thing to check is the unloader valve. In many compressors you have a tube going from the tank check valve to the pressure switch. If that is leaking then some of your air is going to leak out by the pressure switch.
As far as I can tell the belts not slipping. I’ll check it next chance I get. (The smoke has no real smell) The flywheel was changed with an oem replacement as the one that was on it had a flat spot that would kick the belt. You could see the spot when you rotated the flywheel. (Think this unit was returned to tractor supply and they resold it as unused. Of course they won’t help me out other than return it but I figured if I fix it I’ll have a good compressor for well under retail. I only paid $150 for the unit after asking if they would take less from the $300 it was marked at) I’ll also check the pressure switch area. I haven’t noticed any air coming from that area. Thanks
Walkers
Well-known member
Most likely culprit is going to be the head gasket or the air pipe in that area.
It could be in the head but if the compressor was returned due to a bad pulley then the pump likely has very little time on it and is likely good. This is basically assuming we have a new compressor with one flaw, a bad pulley. The pulley is replaced but things aren't working right. So I would be checking the parts of the system that could be impacted by a pulley change. That could be a wrong sized pulley (unlikely if this is an oem part). It could be a bad/slipping belt. That could be due to either a loose belt or a damaged belt.
Listening to the compressor as it fills might tell you something. Just after it starts until the end the pump beating sound should be consistent. It shouldn't show as it get higher in pressure.
Now it is possible something else happened to this compressor. Did the flywheel get damaged in shipping? If yes, how and could that have damaged the pump? It might be worth pulling the head to check the valves. I'm not sure if that would require a new head gasket. An extreme move would be too replace the pump with one of the HF 3hp pumps. They work well enough and are only a bit over $100 when you apply a HF coupon. Still, that wouldn't be my first choice.
Listening to the compressor as it fills might tell you something. Just after it starts until the end the pump beating sound should be consistent. It shouldn't show as it get higher in pressure.
Now it is possible something else happened to this compressor. Did the flywheel get damaged in shipping? If yes, how and could that have damaged the pump? It might be worth pulling the head to check the valves. I'm not sure if that would require a new head gasket. An extreme move would be too replace the pump with one of the HF 3hp pumps. They work well enough and are only a bit over $100 when you apply a HF coupon. Still, that wouldn't be my first choice.
Definitely know it was a bad pulley. Maybe ill try a new belt also as it was the one that came with the unit and maybe its stretched or damaged some and is slipping. The other issue i know it had was the Check valve was bad and would bleed pressure back to the head as when it built 100PSI i could not restart the pump. I changed this out also along with new o rings on the fill pipe as they looked damaged when i took it off. If it gets a little nicer today i will probably pull the head and check the valves and maybe even the piston rings see if something may have been damaged there. Who knows what this thing actually went through. Last resort will be the HF pump, maybe a rebuild of this pump will be in order who knows
Was it the check valve or the unloader that was bad? When the pressure switch is off (motor not running) it should be open. If your check valve is bad you should see a continuous flow of air out of the unloader when the pump is off. If the unloader is bad then you won't hear the psshhh sound when the motor shuts off.
kelpaso1
MEMBER EMERITUS
Small metal piece of something has been bouncing around in that cyl for quite some time. I wouldn't worry so much about the piston but that head needs some careful sanding to clean up that mess.
MacMcMacmac
Well-known member
Holy **** that thing is motoring.
kelpaso1
MEMBER EMERITUS
I never understood why people seem to think they HAVE to drain their comp of all the air you just paid for pumping it up when done with your project. Just shut off the air valve and leave the compressed air in the tank.
Look again. Both pistons look the same, other than the color and the center of both pistons are machined and smooth, no marks. That weird texture is from the factory.
kelpaso1
MEMBER EMERITUS
Err that's what I said, don't worry about the piston.
Perhaps I misunderstood. what do you mean in the red? There was nothing bouncing around in the cylinder, just the head. That is why I mentioned the pistons.
What all were you going to replace? The valve plate, a couple gaskets, about $75. I was just wondering where the rest of the money is to come up with $300?
Walkers
Well-known member
I wonder if that head was really off that compressor? Beat up head but no marks on the piston…
kelpaso1
MEMBER EMERITUS
Ya that is quite possible. Anytime I have seen a head beat up like that there is usually marks on the piston top also.
Walkers
Well-known member
If there is no scoring on the walls visible, I would just fix the head and run it. The rings and bearings are usually the last to go by far, unless it was run dry ( which would cause scoring).