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Freightrain

Compressor feed line replacement

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What are you guys doing for replacing the old copper line on a B model?

Went to move truck and heard a hiss noise after shutting it down.   Found a pin hole in the feed line off the compressor, in the Z bend right off the head.   Seems my flexpipe off the turbo must have sunk a touch and rubbed a tiny hole in the line.  I desperately need the truck this weekend.  I soldered the hole shut for now, will likely wrap with a piece of hose and hose clamp it for extra protection.  

I know most newer trucks use a stainless flex line and hope to leave work after lunch and do some checking around town and see what I can find.

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The new stuff is teflon DOT approved.  Still have one truck on copper.  Others were so banged up and got replaced with the new.

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Will it bend around stuff?  I need the ol zig zag to clear the exhaust.   Typical DOT plastic will not bend very sharp.

 

The majority of the truck(mostly the back) is all plastic, along with anything I added up front beyond original plumbing.

 

 

Edited by Freightrain

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3 hours ago, Freightrain said:

Will it bend around stuff?  I need the ol zig zag to clear the exhaust.   Typical DOT plastic will not bend very sharp.

 

The majority of the truck(mostly the back) is all plastic, along with anything I added up front beyond original plumbing.

 

 

It will bend within reason.

It is special Teflon (PFTE) hose that can take the high temp. that the compressed air comes out of the compressor discharge.  A good truck store will have it on the shelf.

I have a 6 ft or so section between the compressor and air dryer on the B75.

 

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Ya, they have it.  Just not the right fitting for my compressor.  I need to make a block so I can put an AN fitting on it to fit the new style hose.

Looks like I need to maker work for the weekend and tear into it Monday.

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Uugh.  There is always a glitch...

 

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you gotta run at least some heat resistant stuff back 4-5 feet. the compressed air is HOT and it will melt the regular black nylon air line. i think i did run 5/8 copper off the compressor of my B then went to a flex stainless on the transmission then nylon from there. i tried finding 3/4 copper like the original and came ip empty then just went with 5/8 and changed the block on the side of the compressor

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I ran the dot Teflon stuff with the stainless braid from the compressor to the wet tank.  The ends that where on my truck where reusable just had to get new compression rings for in them.   What I ran into was the line was a size bigger then what is common today.    Like said above you can't use regular plastic line off compressor it won't hold up to the heat.   

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I do not know about the discharge line off the compressor but the intake off the air cleaner is the same as heat pump air conditioner copper used for home units . I used the teflon stainless braid from Truck Pro to the copper line to the tank .

 

 

 

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16 hours ago, Maddog13407 said:

you gotta run at least some heat resistant stuff back 4-5 feet. the compressed air is HOT and it will melt the regular black nylon air line. i think i did run 5/8 copper off the compressor of my B then went to a flex stainless on the transmission then nylon from there. i tried finding 3/4 copper like the original and came ip empty then just went with 5/8 and changed the block on the side of the compressor

 I went to a HVAC commercial contractor and they had a couple feet of 3/4 OD soft anneal copper tube in the scrap bin. They use 3/4 SACT in most all commercial AC, Heat Pump installs. Got it for my mixer in swap for a coffee.

Edited by 41chevy
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