Good evening fellow bus folks,
We're traveling about the western US in our DL3-45 - 1993. About a week ago while driving a freeway, our bus suddenly lost power, or so I thought. I heard a quiet pop, and then our speed rapidly dropped. I was able to get to the side of the road. However I noted that all systems were perfect as per the gauges and the engine was running strong. Further checks showed that the parking brake had been applied, that was the "pop". Back to gauge checks; they showed our air pressure to be at about 140 on the front tank and 135 on the rear tank. Never seen that before!! Too much air, so it applied the parking brake. Well, I got the pressure down, idled the bus some, and all seemed OK. So I resumed the journey albeit watching the air pressure gauge. I noticed that the rear tank was now only showing a very minimal range, say, 116 - 122. Anytime pressure reached 116, it would fill back up to 122 and the air dryer releases the pressure. IIRC the pressure would normally start to build up around 100 or so... it's a bit hard to read the gauge at the lower end. So starting to build up air at 116 is unusual. Resuming the journey, after a few starts at 116, and applying the brakes again, the entire air system resumes normal operation and has no more troubles the rest of that days' travels. starting at around 100 (not sure here) and off around 120. Next day, again starting off, the first few minutes, my range is 116-122, a few brake applications, and then air pressure drops to the normal range. This is now the pattern. I do release air from the release valve in the back of the bus (drain daily). Though, I'm much more consistent after this issue started.
Is there something I can check while out on the road? Or a nice, simple ,easy fix? ;D
Or a maintenance item I need to take care of?
Thank you folks for any input!!
Safe travels, Phil
You can try changing the governor on the compressor (20 bucks) that is a easy job on the road,that is only 1/2 of the puzzle the governors controls the unloader valves inside the older compressors. that is more of a job you need to drain the cooling system and remove the compressor head to change those,I never change a governor without changing the unloader valves I keep a case in the shop,Give the governor change a shot 1st you could get lucky and it is easy, a broke control line from the governor to the dryer can cause one to over build PSI too
Thank you Clifford!, Phil