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Joe45 06-20-2019 09:52 AM

Air Brake/AC for Pneumatic Tools?
 
Is there a way to use the air brake tanks to also run pneumatic tools?


Also:
I pulled out the AC system and have two compressors still sitting on the engine.
Is there a way to turn the old AC compressors into air compressors to run power tools?

john61ct 06-20-2019 11:06 AM

AC can mean alternating current

in this context I read as Air Compressor.

Then you have aircon. . .

CHEESE_WAGON 06-20-2019 11:24 AM

Quote:

Originally Posted by Joe45 (Post 333246)
Is there a way to use the air brake tanks to also run pneumatic tools? Also:
I pulled out the AC system and have two compressors still sitting on the engine. Is there a way to turn the old AC compressors into air compressors to run power tools?

I wouldn't recommend trying to use A/C compressors for such a purpose. They are a different design and if I'm not mistaken recirculate a small amount of oil with the refrigerant within the system. Not saying it can't be done, you just may not be happy with the results.

Air brake systems have a governor cut-out set at 90-120 psi. There is a blow-off valve if the system exceeds 150 psi. It might be possible if your air tools don't pull more pressure than the compressor can deliver, or more volume than the tank can supply (these tanks are pretty small and will discharge quickly). However, these systems are known for building a bit of water and oil in the supply tank, which is why there is a drain cock that has to be opened to rid the system of these contaminants. Again, not saying it CAN'T be done, but the results may not be what is desired.

FWIW, I do know that there are hoses for airing up tires that are made to connect to a Class 8 tractor's service line, which can deliver full supply pressure to the trailer. This is very temporary use, though.

I'm not sure what your aim is here, but if you're wanting to do more than just have temporary air supply for working on your rig, you might think about using the existing brackets to install a made-for-the-purpose compressor, and plumbing a second, larger tank for the supply volume you will need. Keep in mind, though, fuel costs a lot more than electricity. If you just need a temporary air supply for working on your rig, I'd just buy an air compressor with an appropriate-sized tank. Just my $0.02.

somewhereinusa 06-20-2019 12:37 PM

The problem isn't so much pressure as volume. Any kind of grinder/sander/saw usus a large volume of air. An impact uses less volume but, you would still spend a lot of time waiting for it to catch up.

Danjo 06-20-2019 01:06 PM

Oh man! Engine-driven compressed air! Iíve been envious of those who have adapted their air brakes to run tools.

A quick search comes up with a company named Underhood that makes add on compressed air systems.

And then I thought; how am I running that when Iím working on my engine?

Still feels worthwhile to find a compressed air solution to run air tools. Might need to go with battery powered impact wrench and ratchet.

o1marc 06-20-2019 02:05 PM

4 Attachment(s)
I did it on mine, tapped into the lines out the back of the air tank. It does have it's limitations as far as the air needed for some tools. But it's handy for other things like filling tires and such.

Danjo 06-20-2019 02:09 PM

Quote:

Originally Posted by o1marc (Post 333298)
I did it on mine, tapped into the lines out the back of the air tank. It does have it's limitations as far as the air needed for some tools. But it's handy for other things like filling tires and such.

Well done!

Brad_SwiftFur 06-20-2019 02:11 PM

I've use my truck's air supply for all sorts of air tool usage. No reason you can't do the same with a bus (and I will at some point.) Just have to be mindful of air supply and supply/recharge rates, but it will work.

Joe45 06-20-2019 02:36 PM

This bus has two Air Conditioning pumps. I'm thinking they can keep an auxiliary tank filled up pretty good. As far as lubrication, I'd put oil in them. From what I've read, they are usually lubricated by the oil in the AC system, and I'd just need to put oil in intake the line.
Problem is figuring out how to do it!

Iceni John 06-20-2019 02:37 PM

I have a small Harbor Fright dual-tank 120VAC compressor that's connected through an inline filter (that takes a surprising amount of water out of the air on humid days) to the bus's accessories air tank for the seat/wipers/horn/door/etc. This air supply also feeds three air outlets around the bus for inflating tires and running air tools. I put in a valved connection between the accessories tank and the bus's brake tanks so I can air up the entire bus from my electric compressor or from outside air. On the electric compressor's tank drain I have a quick-connect Industrial connector and an adapter with an Automotive connector, allowing a tow truck to easily connect its air to my bus after I open the Accessories-to-Brake valve. So far, so good.

John

Wornout Wrench 06-20-2019 02:46 PM

I guess since I joined this forum for information sharing, I should start to share.

Yes you can use your bus air brake system for running air tools.

One of the service trucks I used to have used the truck air system.

As stated above, you need the volume.

My shop truck was a Freightliner FL80 4X4 with a 3126 cat. When they built the truck, my boss was being cheap and didn't want to spend the money on a separate compressor package. So the company that built the service body installed a 60 gallon air tank and plumbed it into the truck air system.

So here is the deal, it worked but depending on what I was doing it could be a little slow.

I would always have the truck up on a high idle, usually in the 1000 rpm area, worked night shift so also running a ton of lights, all incandescent. As long as I wasn't using too much air, it would keep up not to bad. So that would be a 1/2 impact most of the time. You just learned to undo a hand full of bolts, wait for the air drier to fire off, do another batch, wait for the air drier...

If I wanted to use a drill or an air grinder then you had to run the RPM's up to about 2000.

I did run a 1" impact off the system. Have the engine at high idle, run a bolt, wait for the air drier to fire off, run a bolt, wait for the air drier...

The air drier unloading means that the compressor has reached its governed setting for those of you who are wondering.

The cost of fuel to run that truck like that day after day, year after year would have been incredible. Putting a different system in would have made way more sense.

If you run it off the bus air tanks, the tank volume is not there so you will only get a short blast of the higher pressure air. Also don't forget that the size and length of the hose are all factors.

Honestly, my last several years as a mechanic before I retired, I was running cordless impacts, drills and grinders for about 90% of my jobs.
I had to drag my 3/4 impact out for the wheels on our trucks, my cordless would not quite do the 500 foot pounds needed to remove the tires.
Today's cordless tools are getting to be pretty decent.

As for using the old air conditioning compressors, nope.

As far as the underhood compressors, they rock. make HUGE air but what a pain in the butt, and very pricey. Have had 3 trucks with them over the years..
I was field service for years, so 1" impacts, Arc Air torches (heavy gouging in thick steel, you need huge amounts of air), air lances for blowing out radiators and cleaning things out/off.

The latest ones we used were Hydraulic PTO driven, remote mounted. They were nice. Could hide them just about anywhere. Like a skoolie, you are always looking for places to hide things on a shop truck.

Sleddgracer 06-20-2019 03:26 PM

Quote:

Originally Posted by Joe45 (Post 333304)
This bus has two Air Conditioning pumps. I'm thinking they can keep an auxiliary tank filled up pretty good. As far as lubrication, I'd put oil in them. From what I've read, they are usually lubricated by the oil in the AC system, and I'd just need to put oil in intake the line.
Problem is figuring out how to do it!

in days gone by I'm used the compressor from refrigerators/freezers as air compressors - they don't pump a lot of air

Joe45 06-20-2019 08:00 PM

Thanks everybody.


I saw this video and it seems like a doable thing. There's a good amount of humor in it, but seems like a sound option, especially with two compressors, and installing a tank for them.


https://www.youtube.com/watch?v=tA-KQCDDkEE



Also these articles:


On-Board Air for Jeeps Using the York Compressor


https://articles.jeepforum.com/York_On-board_air


https://www.quadratec.com/c/referenc...tems-explained

john61ct 06-20-2019 09:50 PM

Quote:

Originally Posted by Wornout Wrench (Post 333309)
You just learned to undo a hand full of bolts, wait for the air drier to fire off, do another batch, wait for the air drier
...


The cost of fuel to run that truck like that day after day, year after year would have been incredible. Putting a different system in would have made way more sense.

Wasted labor costs even more so.

Wornout Wrench 06-20-2019 10:51 PM

Quote:

Originally Posted by john61ct (Post 333463)
Wasted labor costs even more so.

Oh, I ran that past the boss, but he was one of those guys that unless it was his idea, it was wrong.

So we made do.

Mekanic 06-26-2019 08:16 PM

Quote:

Originally Posted by Joe45 (Post 333246)
Is there a way to use the air brake tanks to also run pneumatic tools?.......

I did exactly that on my U-RV
also used 1/2 inch diameter hose & fittings so I. Could run my 3/4 drive impact.
I put a quick connect at the rear bumper.
Works like a charm.


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