not buildin air pressure

[sbdoss2003]

I have  a 1987 bus w/ 8v92 for power,  It will not build air over 50 lbs....has no leaks , compressor just shuts off at 50..... worked fine when parked last year..Any help will be greatly appreciated

[bevans6]

That would suggest that the governor is telling the compressor to shut off at too low a pressure, as a first guess.  You could try servicing it, or simply replacing it.

[robertglines1]

if you have shop air try building up pressure first that way...It worked for me...do you have a air drier-have you ever serviced it?just ideas....don't know what was stuck but when I back charged it (shop air) it released...happened after sitting for months..just a few no cost ideas..Bob

[mikelutestanski]

Hello;   The d-2 or governor valve is most likely the culprit and changing that is not much of a problem. I also recommend carrying a  spare valve. They are about  $15.00; usually accessed thru the floor hatch at the rear of your bus.. If it is converted most likely under the bed..
   Two bolts and most likey one or more lines to be changed. Just remember to put everything back like the original. By that I mean to replace the plugs in the proper ports for your application.
    If the governor is just stuck it may be released by shop air as suggested but in my view these systems need to be exercised more frequently than we uusally do . I recommend starting ,running, and exercising your bus at least once a month and more frequently if possible. FWIW..
   Regards and happy bussin  mike

[luvrbus]

Time to service the air dryer