Air compressor seems to be staying on

[jimc99999]

Aha...it looks exactly like the Haldex DA33100X.

https://www.haldex.com/en/na/air-dryerair-line/air-dryers/haldex-newremanufactured/pure-air-plus-air-dryer/da33100x/

Long out of production and only refurb units available. A check valve is under $50, may not hurt to try it. Although by the time I add a dessicant cartridge and purge valve I'm approaching $300, which is the price for a reman unit with cartridge.

 

[96 EVO]

When I saw your pic I was gona say "thats no Meritor Wabco system saver 1200".

Probably wouldn't be difficult to replace it with one though.

[Jobert]

We had a similar situation on ours a while back.  I found that the stainless braided line from the pump to the air dryer had worn a hole in it.  It only leaked when the engine was running and calling for air.  It would build up at road speeds but not at idle.  I raised it up and was underneath and it was where Monaco had created a loop in the hose which was to long and ran it through several metal support loops only coated with light rubber and not held tightly in place.  Just the road vibration wore the hole in the line it appeared.  When I replaced it I ran it through the same loops but wire tied it to prevent vibration movement.  Hope this may help. Happy Trails Bert.

[96 EVO]

2 hours ago, Jobert said:

   I raised it up and was underneath and it was where Monaco had created a loop in the hose which was to long and ran it through several metal support loops only coated with light rubber and not held tightly in place.  

Bert, that hose between the compressor and dryer is long for a reason. Look up your air dryer's installation manual (online), and it will tell you the minimum length of line between compressor and dryer. 

On Semi tractors, the air dryers are mounted to the frame, a fair distance from the compressor. On coaches, they are close, therefore the long loop.

It is to cool the very hot air coming out of the compressor before it reaches the dryer. There's no point in having very hot air enter the dryer, then condense downstream in the tanks! There also needs to be a constant downhill slope, so no moisture / oil can collect anywhere in that line!

Edited July 5, 2022 by 96 EVO

[Jobert]

If memory serves, that was about a 12-14' line or longer, and the air dryer is more than 10' away from the compressor, I did keep it the same length and routing, just tried made sure it couldn't rub another vibration hole in it.

[96 EVO]

My dryer is about 3' from the compressor outlet, so the long loop forward then back is necessary.