Weird air system issue

[luvrbus]

I can try to get a pic of the top just to confirm.  Thanks so much guys!!!

Look up Bendix K109119 and you can see the one Kevin is thinking of ,yours will use the other number I posted. Kevin and I have been friends for long time he has the pleasure of working on the newer stuff, he is one of the best at working on the electronic controlled engines 

[JT4SC]

Look up Bendix K109119 and you can see the one Kevin is thinking of ,yours will use the other number I posted. Kevin and I have been friends for long time he has the pleasure of working on the newer stuff, he is one of the best at working on the electronic controlled engines

Done.  I ordered the part # you gave me and will be here in a few days.   Here's what I'm going to do either this weekend or next:

- Replace the governor

- Replace the unloader valve

- Change out the air dryer (is there just 1 air dryer, or is there a separate one for the brakes and a larger one for the overall air system?).  I can see the huge one in the front of the bus, but not sure if there's another one somewhere else?   

- Delete the AC compressor belts and cap the air lines that go to the air piston belt tensioner (it's also leaking air bad).  I'm going to eventually remove the OTR AC system and go with a mini split anyways, so this will start that project. 

You guys see any issues with any of these plans?  I'm assuming it's ok to simply cap the air lines to the belt tensioner?

[luvrbus]

It just has the 1 air dryer up front by the axle, if you are careful you can reuse the head gasket using the "right stuff" sealant, they make several different head gaskets for that compressor, when you buy the kit they always seem to have the wrong firggin gasket  ,if you do need a gasket you can match it on  E Bay for under 20 bucks compared to Fleetprides 35 bucks

[JT4SC]

It just has the 1 air dryer up front by the axle, if you are careful you can reuse the head gasket using the "right stuff" sealant, they make several different head gaskets for that compressor, when you buy the kit they always seem to have the wrong firggin gasket  ,if you do need a gasket you can match it on  E Bay for under 20 bucks compared to Fleetprides 35 bucks

Thanks Cliff!!!

What about the check valve - is there supposed to be a check valve on this steel braided line in the picture attached?

[luvrbus]

Thanks Cliff!!!

What about the check valve - is there supposed to be a check valve on this steel braided line in the picture attached?

[luvrbus]

The C in the shop doesn't have a check valve on the discharge line ,it does have a small drip tank where it connects to drain tied to valve to use shop air to air the bus up inside the rear door ,the check valve is at the front tank,that braided gets hot, real hot so they don't restrict flow with a check valve. I had to replace that hose on a MCI man it cost almost $400.00  ($397.80)

[JT4SC]

The C in the shop doesn't have a check valve on the discharge line ,it does have a small drip tank where it connects to drain tied to valve to use shop air to air the bus up inside the rear door ,the check valve is at the front tank,that braided gets hot, real hot so they don't restrict flow with a check valve. I had to replace that hose on a MCI man it cost almost $400.00  ($397.80)

Ok cool I'll look for the check valve at the front of the bus.  Thanks!!

[JT4SC]

Good morning guys,
Still chasing gremlins on the air system, I've located what I believe may be the issue - this relay valve (pic attached).  Only problem is I don't know if this is a Bendix R12 or R14 relay valve?  Do you guys know?  Is there an easy way to tell while it's still in place, or does it have to come out to know for sure?

[luvrbus]

Either will work for you the only thing different is the R-14 has a anti compound feature to work with the spring brakes it is a upgrade from the R-12 ,there will be a small metal tag on the relay on one of the bolts that identifies the relay, the prices on the relays are all over the map,NAPA quoted me over 400 bucks for new Bendix R-14 I went with Midland I not much into the rebuild stuff, but the kits are cheap and they are easy to rebuild unless the bolts strips or break off. They will have different cracking pressure that is why you need the tag from it ,the front relays have a higher cracking pressure so the rear axles apply first most if the time the front will have a 3 to 4 psi cracking pressure   

[JT4SC]

Let me tell you guys, I'm having the time of my life with this bus (heavy sarcasm)!  While chasing the air pressure issue we noticed the brake chamber on the passenger side drive axle wasn't disengaging, even when releasing the parking brake and/or hitting the brake pedal. 

So I bought a new one and installed it today.   The brake changer came with the push rod in, we installed it that way, and when we aired up the bus the rod came out and engaged the brake, which I believe is supposed to happen since the parking brake was engaged.  But when I disengaged the parking brake the push rod stayed out, which is the exact same problem we had with the original brake chamber. 

So I have to assume the issue is inside the drum somewhere?  Any advice on what could be keeping the rod from disengaging?  I've attached a picture showing the position the push rod is stuck in for your reference (you'll see an air line is not attached, that's because we were in the middle of  troubleshooting). 

[luvrbus]

If disconnected and will release with air pressure applied, then it is inside the drum, if you have automatic slack adjusters those things are terrible about binding and not letting the parking brakes release on the D-3 system, check your air pressure it should be 90% of showed PSI to release the D-3 and should read 0 when released on the port.The older buses love to throw you curve balls and most of the time it is simple problem. A friend did a brake job on his Eagle and one side was not working as it should we found that the supplier sold him 2 right handed S-cams that he installed after a day of searching for the problem         

[JT4SC]

Is there a parts supplier that is good at dealing with these older buses?  While working on the brake/air issue I found there has been an oil leak I believe where the bearings are located, which got oil all over the brake drum, pads, etc. 

I'm looking to replace the brake shoes and the axle seal/gasket, however when I plug the part #'s in to Google there's zero as far as places to buy these things.  I called NFI and they said the parts have been discontinued and they can't help.

[luvrbus]

Luke at 856-794-3104,Coach Bus Parts 800-724-8464 any bearing supply can match the seals or even Fleetpride or Napa and any friction shop can reline the shoes, Las Vegas is close to me, so I buy from P&O
702-384-2530  there is another supplier in Vegas but I don't remember the name but I buy studs there 

[JT4SC]

Luke at 856-794-3104,Coach Bus Parts 800-724-8464 any bearing supply can match the seals or even Fleetpride or Napa and any friction shop can reline the shoes, Las Vegas is close to me, so I buy from P&O
702-384-2530  there is another supplier in Vegas but I don't remember the name but I buy studs there 

God bless you Cliff!!