Community Forums

Ldcrowder · 09-14-2021, 03:38 AM

Help! Our coach is eating air dryers! We have had our 2008 Monaco Camelot for 15 months. We had multiple air leaks to track down and fix and one was our 13 year old air dryer. Not sure if it was leaking from when we bought the coach or not, since we had other air system leaks as well and did not find the air dryer one for 9 months. The air dryer was functioning ok, just would leak down our air tanks after 8 hours or so. The original wabco air dryer was leaking from the front of the regeneration valve. We replaced it with a new cheap direct replacement. It worked fine and did not leak; then after 3 months was leaking from above the purge valve. We returned it and replaced it. It worked fine and did not leak; then after 3 weeks was leaking from what looked like a pin in the housing near the outlet valve. We figured it was just cheap construction, and got a refund; and bought a new wabco direct replacement same as the original (system saver 1200). It worked fine and did not leak; then after 3 weeks was leaking from the front of the regeneration valve like the original one. The system airs up to 115 psi, purges, regenerates for 15 seconds and works fine; It just leaks out our system air down over 8 hours to 40 psi front tank and 65 psi rear tank. I can't believe we got 3 bad air dryers, especially since they did not leak until weeks or months later. Is there something else that might cause them to develop leaks especially from the regeneration valve???

Thanks so much!!!

rpasetto · 09-14-2021, 05:48 AM

Many years ago I was advised against using any "clones" and to stick with the OEM Meritor-Wabco air dryer cartridge. It's hard to say if that 'cheap replacement' you tried first could have possibly caused the problem, but it could be the air dryer itself.

Hopefully somebody here can shed more light on your problem.

twinboat · 09-14-2021, 06:45 AM

First, system pressure should be 125 PSI. You should address that.

Once an air dryer purges, it sits with no air in it to let moisture out the bottom.
The main line out of the air dryer should have a check valve that prevents air from back feeding from the tanks to the dryer.
Find that and see if its got any carbon buildup on the inside.

96 Wideglide · 09-14-2021, 12:42 PM

Your regeneration valve will use about 10psi of supply, and secondary tank pressure to dry out the filter desicant, immediately after purge.

I had an issue with my original Merritor dryer randomly releasing pressure from my tanks, long after engine shutdown. I replaced the dryer with a clone, and other than a bad filter that came on the dryer, have had no other issues.

I'll only buy genuine Wabco filters now!

Ldcrowder · 09-14-2021, 12:48 PM

Yes it does the 10psi drop after purge. Using soap you can see it bubbling constantly during loading and after and even with the engine off.

Ldcrowder · 09-14-2021, 12:50 PM

We are going to Cummins in Coburg OR but they said they don't deal with air dryers. They suggested the Rev group, but they no longer actually answer the phone to set up service appointments. Any suggestions for a good diesel mechanic for air systems??? We are traveling through WA and OR.

Thanks,
Les

96 Wideglide · 09-14-2021, 12:58 PM

Sorry, I don't.

Little surprised a Cummins shop doesn't deal with air dryers

!

vito.a · 09-14-2021, 02:03 PM

A not so long shot, give Source Engineering a call. These guys were managers at the original Monaco factory. Anytime I've had a problem they have been very helpful. If they don't work on air dryers they will know someone that does.
Source Engineering Inc | Custom RV Chassis | Eugene, OR
Source Engineering
458-207-9442
25375 Loten Way
Veneta, OR 97487

Ldcrowder · 09-19-2021, 12:13 PM

Quote:

Originally Posted by 96 Wideglide

Sorry, I don't.

Little surprised a Cummins shop doesn't deal with air dryers

!

We were surprised too.

Ldcrowder · 09-19-2021, 12:14 PM

Quote:

Originally Posted by vito.a

A not so long shot, give Source Engineering a call. These guys were managers at the original Monaco factory. Anytime I've had a problem they have been very helpful. If they don't work on air dryers they will know someone that does.
Source Engineering Inc | Custom RV Chassis | Eugene, OR
Source Engineering
458-207-9442
25375 Loten Way
Veneta, OR 97487

Thanks so much!!!