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Air dryer bypass

Can anyone walk me through bypassing the Haldex air dryer.  We are stuck near Robert LA off I-12.  The purge valve on the air dryer is leaking.  If I push up on the valve it quits leaking.  So I stacked some washers and a couple of quarters under the purge valve cover.  This allows me to build about 60 psi but now I have air coming out of the top port and from under the rubber cover of the governor (maybe it always was but I discovered the purge valve first?).  I assume to connect the in and out lines together but what to do with the small lines?  We are headed to South Padre Texas for a week where I can get repairs.  Thanks in advance for any ideas.
Mike

Re: Air dryer bypass

Reply #1 –
One omission...prior to the washer and quarter trick I could only get 15-20 psi. 

Re: Air dryer bypass

Reply #3 –
Once you bypass the dryer using the correct ¾" JIC fittings, there is ¼" line from the wet tank that may need a plug or cap. Stop and drain water out of all three tanks fairly often, say every hour or so. When I ran with the dryer bypassed, I was surprised at how much came out of the drains after an hour or so.
Don
Quote from: Jet Doc –
Can anyone walk me through bypassing the Haldex air dryer.  We are stuck near Robert LA off I-12.  The purge valve on the air dryer is leaking.  If I push up on the valve it quits leaking.  So I stacked some washers and a couple of quarters under the purge valve cover.  This allows me to build about 60 psi but now I have air coming out of the top port and from under the rubber cover of the governor (maybe it always was but I discovered the purge valve first?).  I assume to connect the in and out lines together but what to do with the small lines?  We are headed to South Padre Texas for a week where I can get repairs.  Thanks in advance for any ideas.
Mike

Re: Air dryer bypass

Reply #4 –
Thanks for the link Chuck.  I searched for purge valve leaking not air dryer bypass so this didn't show up.  Thank you Don for the info in Chucks link and your response at this late hour.  We are in a gas station parking lot for the night.  Daylight and rest may make everything better.  Some rum isn't hurting either.  😉

Re: Air dryer bypass

Reply #5 –
Quote from: Jet Doc –
I have air coming out of the top port and from under the rubber cover of the governor (maybe it always was but I discovered the purge valve first?).

Mike,

This may be your main problem. The governor may be stuck telling the dryer to purge.

Mike

Re: Air dryer bypass

Reply #6 –
I agree with Mike - FIRST replace the D2 governor and see what happens.  Go from there.  If you don't have a spare D2 try any nearby truck stop, truck repair shop or a NAPA store.  Don't worry about the pressure rating on any D2 you find - it can be adjusted after installation.

Replace Bendix D-2 Air Compressor Governor

http://www.plazafleetparts.com/uploads/2/1/9/0/2190100/d-2_governor_maintenance.pdf

Re: Air dryer bypass

Reply #7 –
Mike, sent you a PM with my phone number.  I'm about an hour from you.

Re: Air dryer bypass

Reply #8 –
Update...D2 governor didn't help.  Got a "bypass kit" from NAPA.  Installing it now. 

Re: Air dryer bypass

Reply #9 –
Mike, what is a NAPA Bypass Kit ? We made our own, but was not aware there is a commercial bypass kit.

Re: Air dryer bypass

Reply #10 –
That is exactly what I did.  Two 90's and a union.  We were fixed, fueled and on the road by 11am.  A big thank you to everyone for the info and offers of help/tools. 

Mike

Re: Air dryer bypass

Reply #11 –
There is a good truck parts napa store in Kingsville tx.,would get the dryer going ASAP.
 

Re: Air dryer bypass

Reply #12 –
Mike, Glad you were able to get yourself going.  When you get settled and have some time, could you post the part number for the NAPA bypass kit.  Probably a good thing to have in our parts kit.
Thank you and safe travels.