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Discussion Starter · #1 ·
I'm wondering if anyone knows if there is a factory mounted engine driven air compressor for any of the commercial applications with air brakes or air over hydro brakes? I have some accessorys that will require air so I was doing a little online searching into the compressors that are used on tractor trailers. Unfortunately I don't think they are going to fit under the hood of the Jeep due to there size (I haven't done a lot of searching yet so correct me if I'm wrong here). I can do a york A/C compressor (OBA style) but I would like something that doesn't require constant oiling as the comressor will be running alot. Any ideas? I plan on setting up the system with an air tank and air dryer too.

Thanks,
Anders
 

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Many 6BD1 engines have a factory air compressor.
These are bus and truck engines.

There may be 4BD1 engines with a factory air compressor, but I haven't seen one myself.
 

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Discussion Starter · #4 ·
Dougal,
Do you happen to know how the compressor mounts? As I understand the 4bd and 6bd are basically the same (baring the extra two cylinders of course). I'll try doing some googleing and see what I find.

66gaza,
Are you thinking of running the breather into the compressor or just t-ing off of the breather? I would think if you run direct that it might be to much oil. I do like the idea.

Anders
 

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There's a freeze plug looking thing on the left side of block, between the fuel filter and P/S pump, if P/S equipped, and this is used as the oil drainback into crankcase for a bypass filtration system. Cummins sells a kit that bolts in place [O-ringed] over the hole, after you knock out the freeze plug. You'll see a couple of threaded bolt bosses there on the side of the block, right in front of freeze plug, that hold the adapter plate in place. You could tap in there with the Cummins kit and use it for air supply oiling I suppose?

That's a brilliant idea on solving the compressor oiling problem, never heard of it before! I have a bypass filtration system partially installed but havent tapped into that hole yet. Now, thanks to this great suggestion, I'll tap in another line, for future compressor oiling, THANKS!
 

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66gaza,
Are you thinking of running the breather into the compressor or just t-ing off of the breather? I would think if you run direct that it might be to much oil. I do like the idea.

Anders
If my memory serves me correct the breather was direct into the compressor, not teed. In theory this sounds too good to be true you have filtered air that has an oil vapour included to lube aswell. This isn't something I have done personally , I just read it on a forum somewhere.

JimmieD after all the good advice you have given on this foum I am glad to have given you something for you to run with, please let me know how you get on if you give it a go.

Gaza:beer:
 

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Well, thank you, sir, seems we're all here for each other! Also seems that's the way it's supposed to be...:)
 

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Dougal,
Do you happen to know how the compressor mounts? As I understand the 4bd and 6bd are basically the same (baring the extra two cylinders of course). I'll try doing some googleing and see what I find.

66gaza,
Are you thinking of running the breather into the compressor or just t-ing off of the breather? I would think if you run direct that it might be to much oil. I do like the idea.

Anders
Let me know how the googling works out. As I understand it while the the 4BD1T and 6BD1T share piston and valve components, both the front and back end of the engine are quite different. the bellhousing and gearboxes fitted to the 6BD1T's are huge.
 

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Discussion Starter · #9 ·
Let me know how the googling works out. As I understand it while the the 4BD1T and 6BD1T share piston and valve components, both the front and back end of the engine are quite different. the bellhousing and gearboxes fitted to the 6BD1T's are huge.
I didn't come up with a whole lot of info. However I did look into the York stuff a little more and think that I am going to go that route. Between adding the air compressor, an extra alternator(on board welder) and the turbo I'm going to have to get creative with the space I have anyway.

Anders
 

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Any chance you can tap into your PTO, Anders? My NV4500 trans has dual PTO outlets, so even if mine was 4 WD, which it's not, I could run auxiliaries off the 2nd PTO outlet.
 

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Discussion Starter · #11 ·
Any chance you can tap into your PTO, Anders? My NV4500 trans has dual PTO outlets, so even if mine was 4 WD, which it's not, I could run auxiliaries off the 2nd PTO outlet.
I thought about that. I'm going to be running an SM 420, I can't remember if it is the same as the 4500's with dual PTO outlets. My concern was if they would hold up to being in constant use. Most of the applications I'm familiar with the PTO is engaged while stoped to run a dump box or winch, then disengaged to run down the road. Do you think one would be up to the task of continuous duty?

Anders
 

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Oh, I forgot some of them have to be in neutral to use PTO! But as for constant use it's very common on OTR trucks to use the PTO for continuous duty from what I understand. No direct personal experience, but that's what I've understood to be the case.
 

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Oh, I forgot some of them have to be in neutral to use PTO! But as for constant use it's very common on OTR trucks to use the PTO for continuous duty from what I understand. No direct personal experience, but that's what I've understood to be the case.
Many gearboxes have PTO's that mount into the side of them.
I suspect in these such gearboxes, the layshaft that drives it will run whenever the engine is turning and the clutch isn't in.
 

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Discussion Starter · #14 ·
Very good points guys. I wonder if I will have enough room under the Jeep to mount it. More things to ponder. Thanks for the input.

Anders
 

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Hey, Xtrem, I had an intersting score today at a yard sale. Found a very old air reservoir can, used in an auto repair shop in the 40's. It's donut shaped without the hole. Also got a complete Made in USA vintage air compressor, horizontal 25 gallon tank, with single cylinder cast iron compressor driven by a 1hp electric motor, plus whole world of high quality hose. All dirt cheap because it was my neighbor's yard sale :)

So, that old compressor will be just dandy tucked up by the power takeoff belts on front of engine, and the air reservoir can will fit on it's flat side tucked up under the frame! One of these days I'll have onboard air. Then I can use the leftover 25 gallon tank for an air pig as needed, and also have a spare 1 hp motor. Not bad for a few bucks: keep your eyes and ingenuity open, guys!
 

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Discussion Starter · #16 ·
JimmieD thats a great score. One of my buddies has some old copressors laying around, I should do some measuring.

Anders
 

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I hope it works for you, xtrm! I had a compressor taken off a semi truck that I gave to a friend a few months back, and I can't see any difference between it and this one I just got. Tip on thse: try really hard to get an old American made unit, cast iron type. These newer aluminum compressors are mostly Chi-junk...
 

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If you have any "big truck" dismantling yards in your area you might find some really nice small air tanks (probably about 3-4 gallon capacity) that were commonly used on the smaller 28' long pup trailers. I made up a mount and used formed all-thread with fuel hose on the all-thread as a cushion. I formed the all-thread to look like giant muffler clamps. Used two of em to mount the tank. Nice little reservoir for on-board air!
Bob B.
 
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