have a mcnaught K32 grease gun, approx 150tubes of grease gone though it, WAS a great machine, now useless so I took it apart Sunday
this is the machine
http://www.statewidefastener.com.au/images/uploads/GGMK32.JPG
it appears to me to operate as follows
the spring pushes the grease out into the chamber and when you pump the lever the piston pushes grease into the nipple, (there is a valve in the gun to stop the grease going back into the gun barrell when you operate the lever)
I took off the grease pipe from the end of the housing and what appears to be wrong is that the spring is not strong enough to push out the grease from the barrel into the chamber. I was wondering is this supposed to be a vacuum chamber i.e. when the piston returns to the zero position is the vacuum created supposed to suck the grease from the barrell into the chamber????
I removed the pison from the housing and there is an ordinary O ring on it to create the seal which seems fine, is this just simply worn?????? O ring just sits in a slot on the piston, this O ring looks fine to me and the piston slides nicely through the chamber just as you would expect
found an O ring that was lying around and put it in and tried again no luck
the piston is 11.9mm diameter and piston chamber is 12.38mm
I am lost as to what is wrong with the thing, gun is only 2yrs old, using ordinary castrol red coloured grease
anyone any bright ideas?????
this is the machine
http://www.statewidefastener.com.au/images/uploads/GGMK32.JPG
it appears to me to operate as follows
the spring pushes the grease out into the chamber and when you pump the lever the piston pushes grease into the nipple, (there is a valve in the gun to stop the grease going back into the gun barrell when you operate the lever)
I took off the grease pipe from the end of the housing and what appears to be wrong is that the spring is not strong enough to push out the grease from the barrel into the chamber. I was wondering is this supposed to be a vacuum chamber i.e. when the piston returns to the zero position is the vacuum created supposed to suck the grease from the barrell into the chamber????
I removed the pison from the housing and there is an ordinary O ring on it to create the seal which seems fine, is this just simply worn?????? O ring just sits in a slot on the piston, this O ring looks fine to me and the piston slides nicely through the chamber just as you would expect
found an O ring that was lying around and put it in and tried again no luck
the piston is 11.9mm diameter and piston chamber is 12.38mm
I am lost as to what is wrong with the thing, gun is only 2yrs old, using ordinary castrol red coloured grease
anyone any bright ideas?????
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