Is anyone familiar with these air pumps?..I bought this used and it has very little run time on it, however, i think it was run with little or no oil, not sure.
It is a 2 7/8" bore twin cylinder mated with a 5hp motor..This pump has been used on many compressors.This unit took on some water at one time or another as seen on one piston top.
The bottom end is knocking badly in my opinion..I took the entire assembly apart.. Saw a good amount of blackish gunk in oil pan..I literally cannot find anything wrong with it...
Connecting rods are good on both ends, the 2 needle bearings are good, piston pin good, crankshaft journal good..Also, pistons and bores are good..
Heres where the knocking is coming from:
Everyone time i get to top dead center on each cylinder, the rotating assembly gets knotchy..Both cylinders, every time, at tdc..The crankshaft by itself rotates perfectly and smooth with out connecting rods..Again, connecting rods appear perfect to me..Everything is cleaned and oil lubed.Thanks
It is a 2 7/8" bore twin cylinder mated with a 5hp motor..This pump has been used on many compressors.This unit took on some water at one time or another as seen on one piston top.
The bottom end is knocking badly in my opinion..I took the entire assembly apart.. Saw a good amount of blackish gunk in oil pan..I literally cannot find anything wrong with it...
Connecting rods are good on both ends, the 2 needle bearings are good, piston pin good, crankshaft journal good..Also, pistons and bores are good..
Heres where the knocking is coming from:
Everyone time i get to top dead center on each cylinder, the rotating assembly gets knotchy..Both cylinders, every time, at tdc..The crankshaft by itself rotates perfectly and smooth with out connecting rods..Again, connecting rods appear perfect to me..Everything is cleaned and oil lubed.Thanks