Dmurph2016

So think I found the dryer, it’s the big blue thing? 

Just now, Mark T said:

You have to understand, lots of guys are willing to help, but it's not easy without being there ( lol ) the solinoid ?  Depending make ?? They all look a little different. So not easy to describe other than it'll have airlines and a wire or two.  But even if the axle has a tiny leak and something else on the same tank leaks more... there's not enough air to keep the axle up

I completely understand, without being here is difficult and I am trying my best to understand, but I also don’t know very much myself so it is difficult. 

7 minutes ago, MackTech said:

I'm thinking since the air bled out the axle dropped and no air was put into the ride bags.  I've seen that at the plant. Now if air was in there if question it.

 

I'm thinking there is a leak at the ride bag quick release, the solenoid, or it's one of the lines between the solenoid and the quick release or between the quick release and the lift bags.

There is no air in the system so the axkes dropped, or they are overstretched? I’m not sure what that would look like? 
whays the ride back quick release? And what does the solenoid look like

I just snapped a few pics, not sure if they help, but if you need any specific pics let me know and I’ll see what I can do. 

10 minutes ago, Joey Mack said:

some one plumbed the axle to the primary, it needs to be on the secondary. The main supply out of the secondary tank needs a "Pressure Protection Valve" installed at the tank. so that if a failure occurs on the tag axle it wont drain most of the air needed to "Stop"!

Isn’t that the valve that I just replaced? Not on the tank though. I’m going to assume the way it is setup is the way the body manufacture set it up, not sure why you’d go messing with what’s on what system?

16 hours ago, MackTech said:

The green needle is for primary air. The red is for secondary.  The lift axle should be operating off of a solenoid.  When I'm the up position the solenoid will provide air to the lift bags and when in the ride position the air will go to the ride bags.

Now if you have a loss of air when I'm the up position, you'll want to check the ride bags. Then check the solenoid. Check the supply line for the solenoid which is very likely coming from a "red hat" pressure protection valve like you have in your picture.  I am pretty sure the CL pooping is different than the current generation trucks as the newer trucks have an air\elec solenoid pack near the right side front of bogey cross-member.  

Not sure where your solenoid is as the lift axle is very likely an add after the truck was built.

If the lift axle was put on in the mod center at the factory, I don't remember how they did them on CLs.

 

Maybe this might help.

If green is primary then there is a major leak going on. I figured the red would be primary, reason being after 2-3 hours of sitting the red Harley moved while the green dropped down to almost below 60 or so. ( when you flip the switch for the lift axle green needle dropps, and when in the up position as the air drops to 60 the axle will drop down)
I am assuming the lift axle was put on when the body was put on. I’ll have to look for the solenoid, I’m guessing it’s under the bed 

On 4/6/2021 at 6:02 PM, Mark T said:

I'm think'n that no matter what's leak'n on your truck ??  do yourself a favor and replace all four air chambers on the back of it.  I'd suggest 4 MGMs . They cost a lot, and if you don't know how to change them you'd be best to let someone who does. You really can't go wrong with new chambers....unless you don't know how to change them. Between putting air lines back on and cutting the push rod to the correct length, let alone it's not impossible to hurt yourself with the parking brake they're nothing to play with unless you know.  I think some of your leaks are from the air chambers . those gauges dropping with the application look about normal ???  

I’m going to find a shop and have them change them. I was thinking of just having them replace the rubber diaphragm, but it may make more sense to just replace the whole cans for the peace of mind. I have a feeling that could be part of the air leak I’ve got going on

So little update, today I was able to install the new pressure valve. That I purchased yesterday. Take it off try to put the end one one, and the threads the wrong side. 40 min back to the dealer got the right one, put it on and it’s still leaking. ( I didn’t snug it up enough) so I gotta take the fittings off and do it again tomorow. While checking I put the parking brakes off and noticed this was hissing air. Only did it 2ce though so not sure if it’s just coincidental or not. See second video. 
then with the parking brake off, I was pumping the brakes is both needles supposed to drop? The green needle is the one that has the lift axle on it and has been dropping within a few hours of sitting. (First video ) 

On 4/2/2021 at 8:26 PM, Mark T said:

They used to run around south east pa and nj.    They had trucks similar to yours 

It very well could be, the truck came from that area.

38 minutes ago, Mark T said:

That looks like an old Capone truck.

Could be? Not sure what company that is. 

34 minutes ago, Joey Mack said:

its possible that there isn't a dryer. I would expect this year model to have one, It could have been removed by the previous owner, who knows.. judging by the brake chamber picture, i'm guessing "Pre-trip" was not part of the previous owners day. and maintainance,,, well????.. All of us will help him get his truck fixed up.

I figured that there had to be an air dryer but I’m just not seeing it. The guy I bought it from had a few other trucks that he ran, so I am not sure if the drivers were just lazy or what. I will admit I’m new and clueless so I may have overlooked some things when I looking at it, but hey nothing I can do but fix and move on. Chalk it up to life lesson.

attached is a photo of the truck.

I looked and I still for the life of me cannot find the air dryer. I’m not sure what the issue is with that. I called local Mack dealer and they have a pressure relief valve in stock so I will pick that up. I noticed this today, so looks like I’ll also be needing to replace at least 1 front brake can unless the hole is there for performance 😂 so add that to the list.

11 minutes ago, Mark T said:

I'd get the red thing from your dealer by the VIN of the truck . I've seen them at parts places, but not sure the port sizes will be direct replacement on your's.  Charging the truck from shop air ?  not much chance you'll hurt anything. Joey's idea about going in the compressor discharge is a good place, and when it hits @ 120 you'll hear your air dryer go off. ( if you're worried about too much )  Likely charging in the primary tank won't hurt either.  If this truck has leaks from valves you may want to consider finding that air dryer and replacing the desiccant at least.  Only reason I suggested the governor  was it's marked and probably easier to get at....and air will go in the truck much slower through a tire valve in one of those little ports.

I will have to call the dealer tomorrow and find out about the part. 
I was thinking about it earlier today, its going to take forever with the tire valve, so I think going in elsewhere May be faster. I need to find the filter and change that. 
Are the fittings something that I can get locally or will they need to be ordered? 

12 hours ago, Mark T said:

The CLs I had, the air dryer was right in the area about where the back of the transmission is. Mounted inside the frame. ( this doesn't mean your's is )  Yes the tire valve you mentioned, you can put shop air in there. The cutoff/ regulator ( thing with red cap ) if it's leaking, it's shot.  The brake air leak is likely a diaphragm in a service chamber

I’ll have to lift the body up, I’m sure it’s mounted under there. 
If I hook shop air up to the primary tank, will it also fill the secondary? And when it hits 120 or whatever the cutoff is it’ll release? I don’t want to blow anything up. Or should I look for the dryer and then connect into that instead of the tAnk?
For the regulator thing with red cap, is that a dealer only part? I believe it’s a pressure protection valve?
I’m going to assume it’s the diaphragms that are leaking. But going to start with the smaller things first. 

1 hour ago, Joey Mack said:

it may be one of these..

I didn’t see anything like that.. unless it’s under the dump bed. I didn’t see it on the frame. Unless it’s mounted on the engine? There’s no room on the sides as it’s fuel tanks, battery boxes and air tanks on both sides 

25 minutes ago, Mark T said:

That's a cutoff for if the air drops too low. It's purpose is to stop air from going to something less important than brakes. ( like suspension ) they're regulated and colored for how many pounds they allow.  With the truck shut off ? The gauge should drop as the lift axle is put down ( air's going to filling the bags )  there's reservoir ports on the govener that'd probably be really easy to charge the truck with shop air

There’s a tire fill port on the primary air tank, if I can fill it from there?

So I’ll need to replace the cutoff?

Yes, the gauge is going to drop with the truck off and dropping the axle. But after sitting for 2-3 hours the axle is down as it’s lost too much air, so there has to be something leaking pretty good somewhere in that system. The other system loses air but not at that rate. Although with the truck off and press the pedal you can hear air from the back of the truck. So I’m making progress. 

16 minutes ago, Joey Mack said:

its bolted to the frame, mostly on the right side. Its round, it may be 8" across and near a foot tall. (AD-9). or it could be half that size with a screw on filter, like a big oil filter.... jojo

I just went out and looked and I’m not seeing it. It’s also getting dark out so that may be a factor. I’m sure it’s right in front of my fave and I was looking right at it

1 hour ago, Joey Mack said:

If you post a pic of the air dryer, I should be able to tell you port to hook into.. as far as the airdryer popping off..... that depends on how much pressure the air compressor you are using can make, as long as it put's 100 or so P.S.I. into the truck your good.. 125 would be great.. Once again... The line coming off the top of the trucks air compressor, goes under the cab and changes to a rubber braided hose. It goes to the input of the dryer... jojo

I have to look for the air dryer, I don’t know where it’s located. 

1 hour ago, Joey Mack said:

that the air fan control, some have a cutoff on them. I was suggesting hooking air to the air dryer input.  Did you make that happen?

I have to figure out exactly what fittings I need and track some down. Hopefully in the next few days I’ll be doing that. 

So I only had a few min today to use the soap and water before the weather turned to rain, but here’s what I got done. 
stsrted the truck and let it air up until the governor shutoff. Shut the truck off. Could hear some air leaking from the front of the truck, o opened the hood and started spraying airlines. Not exactly sure what this thing is or does but it was bubbling at the red part. Secondly I confirmed that when I flip the switch to drop the lift axle, the green needle dropped. So it seems that there’s a leak somewhere in that system and when it loses pressure, the axle drops. It’s a start. Hopefully when the rain stops o can lift the bed up and start checking under there. As well as the brake cans as I have a feeling that could also be a culprit 

50 minutes ago, terry said:

As joey said be sure to hook some shop air up to it, hard to hear smaller air leaks with a running truck.   terry

That is what I am working on, have to look and see where the fitting goes and what exactly I need. Have to look into that a bit more 

13 hours ago, Vmac3 said:

Oh and by the way,

The CL is an excellent truck.

V

I think it will be once I can track down/stop some of the air leaks!

39 minutes ago, Joey Mack said:

May I suggest making a fitting that screws into the air dryer input, so that you can air-up the truck the natural way. The air will be divided between the Primary and Secondary systems, so that you can test the whole system at the same time...  The fitting is the #12 JIC fitting in the dryer base. The threads in the dryer are 1/2" NPT. you can follow it back to the compressor disscharge line to I dentify the correct one. The line will be metal braded line coming off the compressor, then under the cab it will switch to rubber, and go down to the dryer.. jojo

If I make a fitting and hook it up to an air compressor does the pressure release or will I have to shut the air off myself? What exactly does airing up with a compressor do? 
 

I’ll have to look into it a bit more as I’m not exactly sure what fitting I’ll need or where they go.