Air compressor acting weird

Drain all
air pressure from system and remove the
governor from the compressor. Temporarily plug
the governor unloader port or air line that connected to the compressor. Build air
system pressure until air dryer purges then
IMMEDIATELY SHUT OFF THE ENGINE.
Observe the air gauge in the supply reservoir. If
leakage is within limits, replace the compressor
unloaders

 

The unloaded on a d12 compressor is made into the compressor cylinder head. The only solution is to buy the cyl head kit for $900 or the whole compressor for $1200 from dealer. Sometimes you can find replacement compressors on eBay for around $850

 

please make sure that the "exhaust"port on the governor does not have a plug in it.Sometimes when replacing governor folks plug it accidentally.It only takes a minute to look at.Good luck.

 

I am saying that when putting plugs into governor ports that the port labeled "exh"may have gotten a plug by mistakeThat port has to be left open or have a filter screwed into it..If you installed the governor yourself,you know what I am saying.Been doing this about 15 years and I still sometimes make this same mistake.