Hi all,
I recently got a 2 cylinder Lister diesel given to me. It's about a 400 lb engine so it's not an option for a re-power in a GT. It had crossed my mind to run a hi CFM air compressor with it. I have read about some 4 & 6 cylinder gas engines converted to an air compressor. I remember a lot of years ago a tire shop had a Wisconsin v4 that ran on 2 cyls and pumped air on 2.... not a high enough volume like would be needed for sand blasting.
Does anyone have an opinion on converting a 4 or 6 cyl engine to a compressor and power it with this Lister? I think the Lister is about 20 hp. A 4 cyl diesel would be great but a little harder to come by. Just a pipe dream as i'm always needing something blasted.
Nicholas

How hard would it be to just find a compressor pump? You could look for something made for 3-phase that the average guy wouldn't be able to run and then swap the engine in. I would think in the long run it would be less frustrating.

As far as converting an engine, try looking for something with OHV. Pull the rocker arms (or camshaft if OHC) to keep all the valves closed. Pull all the plugs, and pipe the plug holes to a new pair of pipe manifolds, using check valves at each cylinder. One from filtered air supply to a tee to plug hole, and from tee to tank line, check valves directly attached to tee. The issue with this is that you have # of cylinders x2 of check valves to possibly go wrong, and the plug holes are not a standard plumbing size. You would either have to tap the plug holes for pipe or make up special plug thread adapters.

Your other option is to make a new head, reinventing the wheel with reed valves etc.

Or, you know, just find a 20hp compressor head that would actually be made from the ground up for what you want and have spare parts available.

I actually have access to a Wisconsin V4 and I kind of liked the flat head style engine Less chance of dropping a valve in the cylinder when you replace the original valve springs with weaker ones that would convert it to a 2 cycle.I already have the Lister engine, tank and trailer axle. I think I will use check valves from Grainger, Bore the spark plug ports out to 1/2 NPT or 3/4 NPT if needed. Here is the valve # 5x782. and specs. About $30 each
Inlet (In.)1/2 (F)NPT
Outlet (In.)1/2 (F)NPT
MaterialCast Brass Max.
Flow Range Free Air (CFM)0 to 38 Max
Temp. (F)450 Tap Size 1/8" for Pressure Switch Unloader
DiscPositive Seating Fluoropolymer seat
I know , why did I ask when I have it kind of planned. Because I like to see what others have constructed and maybe see an idea that I could use.
Thank you for the reply, nicholas

Interesting, and it avoids having to use tees.

Sort of like they run the weak intake springs on hit-and-miss so the vacuum of the piston going back opens it up. Do you use both ports/manifolds for the intake, then? Or only drop the spring pressure on the intake side so you can still run an air cleaner?

At least you wouldn't have to worry about burning a valve seat.

Have you calculated out your power requirements, or are you just going to swap out pulleys until it runs about right?