Air Compressor Motor Bearing Replacement?

[gazza2009au]

hey guys i recently bought a PilotAir Compressor from a classified and upon inspection it worked great than i got it home and on the second use it started giving me grief i originally thought it must have been the belt as the motor would keep spinning once near the shut off pressure but the belt slipped

so tonight i pulled the belt off and ran the motor there is the usual whine noise using a mechanics stethoscope i than shut it off and rotated the motor by hand and seems the front bearing sounds sandy like it has sand in it, so im looking at replacing the motor bearings

is there anything i should keep an eye out for? i have never fiddled with a 240v electric motor like this, i know the capacitor can hold a charge am i able to snip one wire at a time (capacitor has 2 wires) without being electrocuted? the wire joiners are the crimp type so only way to remove them is to cut the wires

hopefully someone can help out with advice or have previously done this

compressor came from a fence building tradie im using for anything pneumatic related mostly for a new business i plan on taking from a hobby to professional and part of that is building shipping crates with a nail gun and drills for shipping my goods in

[Chas]

hey guys i recently bought a PilotAir Compressor from a classified and upon inspection it worked great than i got it home and on the second use it started giving me grief i originally thought it must have been the belt as the motor would keep spinning once near the shut off pressure but the belt slipped

so tonight i pulled the belt off and ran the motor there is the usual whine noise using a mechanics stethoscope i than shut it off and rotated the motor by hand and seems the front bearing sounds sandy like it has sand in it, so im looking at replacing the motor bearings

is there anything i should keep an eye out for? i have never fiddled with a 240v electric motor like this, i know the capacitor can hold a charge am i able to snip one wire at a time (capacitor has 2 wires) without being electrocuted? the wire joiners are the crimp type so only way to remove them is to cut the wires

hopefully someone can help out with advice or have previously done this

compressor came from a fence building tradie im using for anything pneumatic related mostly for a new business i plan on taking from a hobby to professional and part of that is building shipping crates with a nail gun and drills for shipping my goods in

The motor start capacitor cannot retain a charge, as in series with the start winding, it will discharge thru the run winding when the motor is stopped, ie the start switch has closed.

You may find the 'sandy' noise you are hearing/feeling is caused by friction of the centrifugal start switch when the motor is rotated by hand. The best judgement of bearing noise would be with the motor running free immediately after it is switched off, and before the centrifugal switch closes.

Chas.

[gazza2009au]

i'll try that tomorrow thanks Chas

[gazza2009au]

took another look at the compressor this evening just as it was getting dark, i checked the bearings with the motor winding down there ok, i took another look at the belt and it could possibly be the belt that is slipping and its making a loud bearing/cracking noise when it slips while the pump is loaded up

as i mentioned i picked up a belt from Pilotair the guy said it was the correct belt but its to big even with moving the motor back

does anyone know of someone i can possibly get a belt custom made?

probably why it was being sold by the seller he knew he couldnt get the right belt for it

[justonething]

Cant really see from the pic, but looks like that it is a A - series belt. You can take your belt to Fenner transmission and looks for one that is slightly shorter than your current (probably stretched) one.

[gazza2009au]

thanks mate much appreciated i went out to the shed and checked the old belt it read A-43 than i went on ebay i found belts of all sizes i think i may need a A-41 which is 60mm shorter luckly they are common for ride on lawn mowers and here i thought i was getting stuck

[justonething]

If it is a 43" original, I'd get a 42" to try first, too short a belt may cause too much stress on the bearings and lead to pre-mature failure.

[Treecycle]

What pressure is the compressor getting to before it cuts out? If it is trying to get too high due to the pressure switch either being faulty or incorrectly adjusted, it could be loading up the belt too much making it slip.
How much travel do you have on the motor mounts? As jot says, one size down might be all you need if the current one is almost tight enough.

[gazza2009au]

i'll measure up the belt tomorrow i cut my old belt so i can wrap it around the pully's on the shortest setting and see how much over hang i have on the belt ends and see which belt i need

the motor only moves around 20-30mm not much at all and by the looks of it tonight the motor was moved to its furtherst point that's why the current belt was slipping so hopefully 2 sizes under fits than i should get a lengthy time of service from the new belt

[gazza2009au]

ok just measured the old belt on the air compressor, new it measures 1100mm now its measuring 1130mm, the next size belt down measures 1060mm im not sure if it'll fit so i may just go with another A-43 and see how i go

thanks for the advice guys