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Topic: Air Dryer Bypass Demo (Read 12627 times) previous topic - next topic

Re: Air Dryer Bypass Demo

Reply #60 –
Thank you Chuck.
As you described it we did the test, pressure gauges climbed to normal compressor cut-out point and stopped.
I will know more once the part gets here and deal with it, but so far so good. The location of the dryer is not bad at all. It is in the back of the passenger side rear tire over the chassis batteries, there is access from the side and from under.

When I am reinstalling the fittings on to new dryer and to screw the hoses on to fittings do i need to use the cheap plumbers white teflon tape or should I get something better? I was at the Home Depot yesterday and noticed for few dollars more there are some newer tapes. I just don't know if i should not use any tape at all or maybe even something different like a liquid tape?

On your previous writings you mentioned about not having to drain the air bags. If i could do that it will give me some more room to work with.

Thank you,
AL

Re: Air Dryer Bypass Demo

Reply #61 –
Glad the test worked!  I wasn't sure what would happen, so that is good info for all on the Forum who might face a similar situation.

It is highly recommended to avoid using any kind of teflon tape on the air system.  All the smart kids on this Forum use a pipe sealing paste made for high temp air systems.  I use either LOCTITE 567 PST or PERMATEX 59214, whichever I happen to find when I go shopping.  You only need this stuff on the pipe thread fittings, such as the ones on the dryer.  Any hose connection with a flare or compression fitting does not require the use of sealant.

Your air bags should retain pressure, even if you completely drain the pressure from your air tanks.  This, of course, assumes no leaks.  Do you have your safety stands with you?  Ideal (safest) procedure would be to raise the coach and insert stands before working.

Re: Air Dryer Bypass Demo

Reply #62 –
A couple of things Al. The quote about the bypass demo mentions the "Isolation Valve". This device was only used up until sometime in 1999, so yours should not have it. The fittings that go on the bottom of the dryer and connect to the JIC fittings that attach the hoses are 1/2" pipe thread where they screw into the dryer. This requires some sealant and some care to tighten up tight enough to seal and still point in the right direction (if they are elbows like on ours). Don't use tape! I like Loctite 567 but that can be hard to find, and Rectorseal or similar should be fine, just be careful to keep it out of the air line.
Don
Quote from: propman –
Thank you Chuck.
As you described it we did the test, pressure gauges climbed to normal compressor cut-out point and stopped.
I will know more once the part gets here and deal with it, but so far so good. The location of the dryer is not bad at all. It is in the back of the passenger side rear tire over the chassis batteries, there is access from the side and from under.

When I am reinstalling the fittings on to new dryer and to screw the hoses on to fittings do i need to use the cheap plumbers white teflon tape or should I get something better? I was at the Home Depot yesterday and noticed for few dollars more there are some newer tapes. I just don't know if i should not use any tape at all or maybe even something different like a liquid tape?

On your previous writings you mentioned about not having to drain the air bags. If i could do that it will give me some more room to work with.

Thank you,
AL

Re: Air Dryer Bypass Demo

Reply #63 –
Don brings up a important point.  Don't remove any of the fittings from the old dryer until you have the new dryer sitting right next to it!  You must carefully note the direction each fitting is pointing, then remove it and transfer it directly to the new dryer.  That way you'll be sure the hoses will line up properly.

Re: Air Dryer Bypass Demo

Reply #64 –
Probably obvious, but don't use any sealant on the JIC (ones with a flare) fittings, just maybe a bit of anti-size on the threads.
Don

Re: Air Dryer Bypass Demo

Reply #65 –
Quote from: Chuck & Jeannie –
Don brings up a important point.  Don't remove any of the fittings from the old dryer until you have the new dryer sitting right next to it!  You must carefully note the direction each fitting is pointing, then remove it and transfer it directly to the new dryer.  That way you'll be sure the hoses will line up properly.
We had to remove the fittings to be able to do the bypass with a connection/joint that we had readily available. However I am aware at the direction they were pointing. I should be ok with that.

Re: Air Dryer Bypass Demo

Reply #66 –
Quote from: Don & Tys (AKA acousticart) –
Probably obvious, but don't use any sealant on the JIC (ones with a flare) fittings, just maybe a bit of anti-size on the threads.
Don
Don I found Rectorseal 5 pipe thread sealant. I am hopping it is ok to use?

__ I am worried about the electrical connection. it is very tight and i don;t know if there is a lock/latch or something.

Re: Air Dryer Bypass Demo

Reply #67 –
If you can't get the electric plug out, try unbolting the heater element and letting it drop down.  Looks like 3 bolts holding it on.  Once it is loose, might be easier to see how the plug locks into place.

I see now how you accomplished the connection between the two big hoses.  Very clever!

Re: Air Dryer Bypass Demo

Reply #68 –
Al, as I recall, the heating element is hard wired to the coach via crimp terminals. It is like a resistance loop you might find if you took a coffee pot apart or maybe a charcoal starter. Just remove the purge valve cover and the screws around it and it should drop right down. You should use some thermal paste when you install it in the new one. Maybe the rebuilt ships with some...
Don

Re: Air Dryer Bypass Demo

Reply #69 –
Should be okay, the boiling point is 330º and the data sheet says to avoid temperatures above 500º, I just like to be safe and a big tube of the 567 Loctite lasts a very long time!
Don
Quote from: propman –
Don I found Rectorseal 5 pipe thread sealant. I am hopping it is ok to use?

Re: Air Dryer Bypass Demo

Reply #70 –
Quote from: Don & Tys (AKA acousticart) –
Should be okay, the boiling point is 330º and the data sheet says to avoid temperatures above 500º, I just like to be safe and a big tube of the 567 Loctite lasts a very long time!
Don
Just can't find Loctite 567 in town :-( If i can get a way for about 1800 mil, i will redo them all when i get back home.

"You should use some thermal paste when you install it in the new one. Maybe the rebuilt ships with some..."  I hope the new/rebuild unit comes with it all.  I am by Home Depot and NAPA is just 4 mil.

Thermal paste like this Arctic Silver Ceramique 2 Premium High Density Thermal Compound ?

Dryer should arrive from Salt Lake City in an hour or less , I hope.  Thank you! all for helping

Re: Air Dryer Bypass Demo

Reply #71 –
Not sure about the Arctic Silver for this application... but I imagine as long as it is thick enough and has a enough volume it should work. Here is a picture of the parts that come in the Air Dryer heating kit from Haldex, as well as the most relevant part of the instruction sheet. I have a 24V new old stock military surplus air dryer with me and I bought this kit for when I get around to installing the new air dryer. You can see the heat transfer grease in the orange cup. Apparently, just "a little dab will do ya" ^.^d
Don
Quote from: propman –
Just can't find Loctite 567 in town :-( If i can get a way for about 1800 mil, i will redo them all when i get back home.

"You should use some thermal paste when you install it in the new one. Maybe the rebuilt ships with some..."  I hope the new/rebuild unit comes with it all.  I am by Home Depot and NAPA is just 4 mil.

Thermal paste like this Arctic Silver Ceramique 2 Premium High Density Thermal Compound ?

Dryer should arrive from Salt Lake City in an hour or less , I hope.  Thank you! all for helping

Re: Air Dryer Bypass Demo

Reply #72 –
I was just able to remove the Air Dryer Heater and it looks just like the one you posted above it is like a ring, so the "electrical" connection i was afraid is also been tackled.
Due to smoke coming from North the Airplane landed late so I am still waiting for the dryer. In the mean time I attempted to remove the dryer. It appears very heavy and I am not so sure right now but being held in its place just with one bolt from under? It is moving around but cant get it out, yet.

Re: Air Dryer Bypass Demo

Reply #73 –
When using air dryer bypass without governor, to keep from building too high pressure, some have opened the wet tank drain a small measured amount, and others have manually adjusted the wet tank high pressure release to a lower psi.
Also along with having an air dryer bypass joiner, having a pair of right-angle fittings already attached to the joiner in the same orientation will make installing a bypass easier.  Often the right-angle fittings in use are very difficult to remove from the failed air dryer, especially on the side of the road.  They are large and tight and seemingly immovable.

Re: Air Dryer Bypass Demo

Reply #74 –
I believe that line from the governor only activates the purge valve on each cycle and does not affect the pressure of the air tanks. Correct me if I am wrong, but I have used that port to operate a spitter valve on a previous coach that didn't have any dryer filter.

Re: Air Dryer Bypass Demo

Reply #75 –
We are all fixed up and hope to leave first thing in the morning. Thank you all for your help. Once again Foretravel friends are priceless, you almost make braking down fun  :) 

Going forward like a oil/filter change just get a rebuild Air Dryer once a year? I understand the bypass valve and all that to use when it stops working unexpectedly but what is the common practice should be? Mine was rebuild by FT 17 months ago and since than we only had about 3-4000 miles. 

Those elbow fittings are not practical & I plan on getting straight ones, anyway.

Re: Air Dryer Bypass Demo

Reply #76 –
I think every two years would be plenty adequate as far as getting "remanufactured" air dryer. Definitions of "rebuilding" varies too much depending on who does it. As to the elbows, our air lines wouldn't meet up with the fittings on the air dryer without the elbows, your must be a bit different.
Don
Quote from: propman –
We are all fixed up and hope to leave first thing in the morning. Thank you all for your help. Once again Foretravel friends are priceless, you almost make braking down fun  :) 

Going forward like a oil/filter change just get a rebuild Air Dryer once a year? I understand the bypass valve and all that to use when it stops working unexpectedly but what is the common practice should be? Mine was rebuild by FT 17 months ago and since than we only had about 3-4000 miles. 

Those elbow fittings are not practical & I plan on getting straight ones, anyway.

Re: Air Dryer Bypass Demo

Reply #77 –
I sure hope can go for 2 years. If it wasn't for the steep core charge i would almost starting to have a spare after 12 months.
Yes for ours straight fittings will work just fine, I wonder why they did not do it like that to start with, who knows.

Re: Air Dryer Bypass Demo

Reply #78 –
Actually, I am comfortable with every three years.  But, I really like the factory (i.e. the factory that made them) re-man, as all valves, heater and filters are new.

Re: Air Dryer Bypass Demo

Reply #79 –
I am happy to just install the Haldex service kit every 18 months per the FT service schedule.