I've often needed a large CFM air compressor and have had tossed around the idea of building one using a spare MB 617.
My plan is to take the air from two or three cylinders by installing check valves in the injector holes and tie them all together for the comp air out. I'm thinking a custom camshaft would be required to open the intake valve every downward stroke of the piston(s). Also, the exhaust lobe would need to be removed to keep it closed (or remove the rocker). The IP injector lines for those cylinders compressing air would be returned to the tank so the IP would still have proper lub to all it's pump elements.

Sitting here scratching my head trying to figure out what cylinder numbers of the two (or three) would allow for smooth running.

That would be an extremely unbalanced engine.

I don't think that would work....why not just use a normal compressor and leave the engine alone?

Sears has their huge-normous air compressor on sale right now.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Why not use a 615 or 616...

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http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

I know for a fact fahr-deutz has a fl4912 engine that has one cylinder devoted to being an air compressor.

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Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?

As long as they would add one additional commandment for you to keep thy religion to thyself.
George Carlin (Wonder where he is now..)

1981 240d (engine donor 1983 240d) recently rebuilt engine hurray! - No more.. fought a tree and the tree won.

pearl black 1983 240d 4speed (Converted!@$$%) atleast the tranny was rebuilt.

A 615/616 would be easier because of it's even number of cylinders.

Contact this book company, supposedly they have a book detailing how to do it.
http://www.lindsaybks.com/

a 617 would an excellent boat anchor as well

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michael cole 1980 300SD gone now but not forgotten,87tdt,90 300te 4matic 95 e320 wagon

You could use one 617 to drive a 616 set up as an air compressor - you'd have enough air to run a jack hammer.

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1984 300TD

I was just at harbor freight today and they have a big compressor unit (just the compressor piston unit) with twin pistons and a giant flywheel with a fan built into it for like $139. Its an oil lubed unit and requires at least 3HP to run it. You could mount one of those (or two) next to a 616 on a platform and run them with belt drive, that'd be one heck of a compressor! If you used two you'd have a 4 piston compressor!

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

My Ford 170 cu. in. 6-cylinder engine lost all compression in one cylinder, so before rebuilding it I disconnected three spark plug wires (every other one in the firing order) to see how it would run on three. It ran, but not very smoothly. I just drove it up and down the driveway a couple of times. I've heard of people plugging the intakes on a few cylinders of an 8 to save gas during the war. World War II that is, the next one after the War to End All Wars.

Which was a few wars before "The Mother of All Wars".

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1984 300TD

.. and spawned The Little War That Couldn't Stop.

Sorry, couldn't resist the off-topid comment

On topic.. prolly work with only one cylinder, but getting it to start on just three might be difficult. Unless you have the 617 lying around collecting dust and a lot of time on your hands you'd probably be better off selling the 617 and using the money to buy a large air compressor or three.

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'83 300DTurbo http://badges.fuelly.com/images/smallsig-us/318559.png

Broadband: more lies faster.

I agree with this.

To get balanced on a 617 would be tougher.

The first two cylinders to put down is easy....the tough part is figuring out how to get the half!

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

how much cfm's do you actually need?

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2001 Dodge Ram 2500 Cummins Turbo Diesel - 4x4, auto, 3.54 gears, long bed
-------------------------------------
'92 300D 2.5 Turbodiesel - sold
'83 300D Turbodiesel - 4 speed manual/2.88 diff - sold
'87 300D Turbodiesel - sold
'82 300D Turbodiesel - sold

Now THAT would be a compressor! Wshew!

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)