How Do I Get This Fitting Loose??

[gus]

Anyone have any good suggestions on how to loosen a 3/4" air brake fitting on the firewall of a 4104? This fitting is leaking air and can't be tightened.

It is almost impossible to get to with a wrench but I managed to get an open end wrench on it and use a crowbar for leverage. All I managed to do was twist the fitting and firewall. All I need now is to break the through-wall fitting then I have another impossible to reach area ahead of the firewall!

I'm afraid to use heat because there is so much oil on both sides of the firewall. I cleaned the engine side but the other side is almost inaccessible.

Unless I can find another way I'm about down to cutting the fitting off at the risk of damaging the threads under it. Before I do that I'm thinking of using a nut-cracker but I don't think it will work well on brass.

[JackConrad]

Gusc,
   Is there a place to put a wrench on the through fitting?  Usually air fittings require a wrench on each of the 2 pieces until it breaks loose. Might also try a line wrench instead of an open end wrench, less chance of rounding off the corners on the fitting. If you use heat, I would only use a propane torch, Oxy-Acet. may get it too hot and melt fitting and/or line. I don't think a nut cracker will work because the fitting is hollow, not solid like a bolt. It will probbly deform the fitting making it more difficult to remove.  Hope this helps and good luck.  Jack

[Eagle]

Soak it with PB Blaster it is a penetrating oil that really works wonders you can get it at NAPA or any Truck parts place.

[wrench]

 If you can put your hand on a plasma cutter, use it to heat the fitting. The flame being very compact & can be trigger only when the tip is at the right spot(pratice before) I used it in very tigh spot & work like  a charm.
            wrench

[n4rsn]

If you can get a hammer in to it. Use a small ballpeen hammer, and use the peen, or the small side. Hit the flats of the line nut. Hit it several times.  The idea is to, peen the nut, so it actually enlarges a small amount, and therefore, comes loose, and does not damage the nut, so it is reuseable.
Steve

[gus]

I don't think I can get a wrench on the other fitting but will give it another try. It is in a really tight spot.

I got the tank fittings out with a propane torch but I'm afraid of heat on this because it is in an oil soaked area.

It is soaking in PB Blaster now.

The ballpeen hammer I had never heard of, I'll give it a try.

Thanks to all, this thing has me stumped.

[belfert]

I tried PB Blaster overnight on a stuck fitting on my bus and it still wouldn't budge.  I ended up using heat from a MAPP gas torch to get the fitting loose.  Mine was brass on brass.  (Yes, a MAPP gas torch was way overkill, but all I had at the time.  I only used it until the fitting came loose.)

Brian Elfert

[gus]

I would use heat but if that oil catches on fire that is the end of my bus, two antique trucks, a '63 Jeep and an antique fire truck.

[JackConrad]

I occassionally have to use heat when working on my bus. I ALWAYS have a fire extinghusier nearby AND a charged water hose. I hang around the shop for at least 1 hour after finishing using a heat source tool just to be sure no fire starts.  Can you get at the backside of the bulkhead with a pressure cleaner or Gunk to clean the area before using a heat source tool?  Jack

[boogiethecat]

Yeah, having a fire extinguisher around (CO2 preferably) is a must in doing a conversion.  The damndest things will get you...

I was raising the roof on my Blurbird and two weeks ago I did a last plasma cut of an annoying rivet.  Prior to doing it I draped the dash area with a silicone banket I have that is absolutely fireproof, to keep the gauges from getting splattered and the windshiled too, not to mention general sparks fro flying around where I didn't want them.

Did the cut and took a look at everything, decided all was well and went off to get a glass of water...but something told me "look again" so I turned around and came back to see flames coming out of the frikking defroster vents !!  So I grabbed the good ol' CO2 and gave er a big blast, fire out instantly.

Turned out a little spark had gotten in the vent tubing and caught some dust in there, and not 30 seconds later it was quickly heading for the major wiring harness.  Fortunately I only had to replace the wires to the shifter lever, and the hose. 

Had I not had the CO2, there would have been absolutely NO way to get to the fire and the bus would have been toast.  A powder extinguisher would not have had the blast necessary to get the goods thru the cracks and to the fire, and it would have absolutely killed all my gauges.  But the CO2 just went WOOSH and it was over.
So you never know.... but DO KEEP A C02 on hand!!

The trouble with a powder extinguisher is that the mess it makes will be worse than the fire, and usually nothing you can recover from, as it sticks to everything and ruins it.
CO2 is clean, it's also cold as well as smothering, so it does a much better job in my humble opinion...

I guess per that other thread, a decent fire extinguisher is my favorite tool.. 

[gus]

The front of the firewall is really hard to get to so I don't think I can do a decent job with my pressure washer.

Right now I'm not willing to take the chance so looks like cutting it off is the next move.

[NJT5047]

Is the fitting still stuck?  If so, have you considered cutting off the line to the fitting so that an impact wrench and socket can be used to remove?  May knock it right off.  Be sure to back the thru hull fitting up with the heaviest wrench you can get on it.
The thru hull may not be useful once disassembled... if it's been overtightened to the max, it's probably distorted.
Good luck, JR

[gus]

JR,

I don't think I can hold the wall fitting agains an air wrench. It is a good idea and if it were a good solid mounting I would try it. It is a 90* elbow which makes it a lot worse. A straight fitting wouldn't worry me so much and would be easier to hold.

The fitting from the air line into the compressor muffler was also over-tightened but the fitting was not distorted. However, the brass ring that actually provides the seal was flattened so much that it leaked and the ring was imbedded about 1/32" into the 3/4" copper pipe. I had never seen a ring flattened like this but I haven't worked with tubing this large either.

The ring is extruded into a semi-flat shape and the nuts run out of threads so it won't seal.

I'm sure the one to the wall fitting is the same way.

These fittings require such large wrenches that I can see why it  isso easy to overtighten them. (1 1/8").

Tomorrow I'm going to start cutting the tube and nut off and probably will take it off in small pieces. I have to be really careful not to damage the sealing ring seat or all is lost.

[n4rsn]

I had to put a new tank in my 4106, the fittings on the new tank were not in the same place the old one was in, so I had to do some rerouting of some lines.

I bought some new flexable air line, and some new fittings for the flexable lines. The line ic called syn-flex. It is a plastic air line, and is DOT approved.   The replacement of the air tank went great, and the lines are holding great.

However, remember, it is a plastic line, therefore, it MUST be kept from heat.  If you use it on on the wet line, from the compressor. Remember this line gets quite hot.
This line is the same size as copper lines, so it can be spliced to copper, and, all the fittings will interchange.
Just a thought
Steve

[gus]

Steve,

Thanks. I was concerned about the heat factor because this line passes part way behind the engine and near the mufflers but is protected by a large heat shield. Copper is just not to be found anymore and I don't think new trucks use anything but plastic.

I was told by the parts store that the new plastic has a pretty high heat rating but they couldn't tell me exactly what the rating is?  I'm going online to see if I can find out for sure. I may have to splice it like you said if it gets too hot.

Plastic sure is a lot easier to work with. The copper is so stiff that I had to remove the air comp muffler to detach the line, it didn't have enough slack to unscrew the check valve and dismantle the connection.

I have to replace my wet tank also but I have one with very close to the same fitting locations plus it has its own mounting brackets. I have two new U bolts on order but don't need them now.