changed 4inch pulley to 6 on 3hp century sing phase 1750rpm motor. comp is champion pump 2stage fresh top end 60 gal.kicking out the air. painted a van and air buffed it.compressor ran and would shut off very pleased' motor did get hot but it got before too' im hoping i dont ruin the motor?looking for a 5hp now that iknow the pump will perform.pictures of the old ge motor is a2hp i had the 6 inch pulley on when i painted the van worked fine ive since changed to the century 3hp and ran cut in cut out cycles continuosly.o to 135 4 min 105 to 135 30 sec aprox.15 cfm im digin it. is this going to ruin the motor?
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pulley change more rpm aircompressor
- Thread starter 46 knuck
- Start date
I did this on an old ('50s) Champion and whole unit ran hotter; and that was with going from an old 2 HP to a then new (20 yrs ago) 5 HP the 2 HP was a 1725 RPM and the 5HP was a 3450 RPM motor, I made a pulley swap to "split the difference" in pump RPM but still sped it up quite a bit;
I think it's Quincy that has the ad about higher output at lower pump RPM = cooler air being produced and a longer lasting pump
I think it's Quincy that has the ad about higher output at lower pump RPM = cooler air being produced and a longer lasting pump
stonesfan68
Well-known member
Compressor RPM = (Motor Pulley PD) x (Motor RPM) / Compressor Pulley PD)
PD = pitch diameter
By using the 6" motor pulley the compressor is now turning at 1.5 times the RPM of the 4" motor pulley.
You need to get the specifications for the compressor and see what the required HP is for the RPM that the compressor is now turning with the bigger diameter motor pulley. The greater the RPM the greater the required horsepower.
PD = pitch diameter
By using the 6" motor pulley the compressor is now turning at 1.5 times the RPM of the 4" motor pulley.
You need to get the specifications for the compressor and see what the required HP is for the RPM that the compressor is now turning with the bigger diameter motor pulley. The greater the RPM the greater the required horsepower.
rmc115
Well-known member
Where did you get a pulley? I am looking for a smaller pulley to slow mine down some. Mike
Tim The Tool Man
Well-known member
changed 4inch pulley to 6 on 3hp century sing phase 1750rpm motor. comp is champion pump 2stage fresh top end 60 gal.kicking out the air. painted a van and air buffed it.compressor ran and would shut off very pleased' motor did get hot but it got before too' im hoping i dont ruin the motor?looking for a 5hp now that iknow the pump will perform.pictures of the old ge motor is a2hp i had the 6 inch pulley on when i painted the van worked fine ive since changed to the century 3hp and ran cut in cut out cycles continuosly.o to 135 4 min 105 to 135 30 sec aprox.15 cfm im digin it. is this going to ruin the motor?
Throw a clip-on type amp meter over your motor near the end of a fill up cycle and check your draw. Compare that to the plate on your motor.
Where did you get a pulley? I am looking for a smaller pulley to slow mine down some. Mike
I recently reduced the size of my pulley. went through this vendor: http://www.electricmotorwarehouse.com/pulley/pulley_sheave_menu.htm Quick shipping and fair price.
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Stones and Tim have it. You need to know the upper and lower speed limits of the pump head you have and be within that range. Then check the current draw on the motor. If your under the FLA of the motor your good. If your running just above the FLA then you can lower the cutout on the pressure and have just a bit lower max pressure. If to far above the FLA then you will have to go to a smaller motor pulley. What you are doing is running blind at this point and without numbers you are at risk.
Can you find your pump model number here http://www.aircompeq.com/rechamp.htm ?
If so post up your model number then we can be of more help.
lg
no neat sig line
Can you find your pump model number here http://www.aircompeq.com/rechamp.htm ?
If so post up your model number then we can be of more help.
lg
no neat sig line
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Steevo
Well-known member
Check Surplus Center for pulleys before ordering elsewhere. They have a good selection and excellent prices:
https://www.surpluscenter.com/sort.asp?catname=powerTrans&keyword=PPT2
https://www.surpluscenter.com/sort.asp?catname=powerTrans&keyword=PPT2
WV Hillbilly
Well-known member
according to the Champion compressor manual I have, the R10 compressor has a rpm range of 400 min/1050 max, the R10 compressor should have a 16.5" flywheel, doing the math (compressor rpm X flywheel diameter) divided by motor rpm, I get this......(1050 X 16.5)/1750 = 9.9 inch motor pulley for max cfm.
The manual shows the R10 compressor puts out .01942 cu ft. per rev. that would equal to a output of 20.4 cfm.
the manual also shows the R10 with a 1.5 or 2 hp motor, so a 3hp motor should be able to handle it fine.
the manual shows a 1.5hp motor with a 5.25" pulley turns the compressor @ 542 rpm, a 2hp motor with a 7.00" pulley turns the compressor @ 725 rpm. so if you figure a 1hp motor would turn the compressor @ 542/1.5= 361 rpms, so a 3hp motor could turn the compressor @ 361 x 3 = 1083 rpms.
If you had a 9.75" pulley on the motor, the pump would be running at 1034 rpms, that would give you an output of 20 cfm.
The manual shows the R10 compressor puts out .01942 cu ft. per rev. that would equal to a output of 20.4 cfm.
the manual also shows the R10 with a 1.5 or 2 hp motor, so a 3hp motor should be able to handle it fine.
the manual shows a 1.5hp motor with a 5.25" pulley turns the compressor @ 542 rpm, a 2hp motor with a 7.00" pulley turns the compressor @ 725 rpm. so if you figure a 1hp motor would turn the compressor @ 542/1.5= 361 rpms, so a 3hp motor could turn the compressor @ 361 x 3 = 1083 rpms.
If you had a 9.75" pulley on the motor, the pump would be running at 1034 rpms, that would give you an output of 20 cfm.
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nehog
Well-known member
The only proper way is to measure the motor's temperature. The motor will have (on its data plate) the maximum temperature it should achieve. A thermocouple embedded in the motor would do the job.
i just came from harbr freight mini digital clamp meter.set meter 200amps 0 to135 psi 9.4 amps 105 to 135 9.2 amps 13 amps at start up. 17 amps recomended on motor . found pulley at electric motor shop used 10.00 you might want to check one around your area.and the fly wheel is dead on along with all of hillbillys imfo.if all goes well at 15.6 cfm im a happy nthing worse than waiting for air we all know that.
trbomax
Well-known member
I have the same compressor/tank unit. It came with a 5 hp @ 1725 and is running a 6" motor pulley.Just for what its worth.