OK the pic below show my current setup. a 3 1/2hp compressor with line run around the shop. to a 3 gal long tank hung on the wall as a water trap, I have two 100 gal tanks T'ed into it and a 50ft hose / lead with a 10 gal tank on wagon wheels.

You know I have plenty of volume for a while. My small compressor works well but I need more umph at times. It can keep a constant 75-80 psi but I want full psi. I do have a few electric motors and compressor motors that I could make a 2 stage but I hear rumor that 3 1/2 HP gas motor can be easily changed over to pump air and are not only quiet but provide lots of air now. No waiting, its air on demand.


Of course I have parts to go two stage but wonder how y'all think of use a lawn mower engine for a new air pump???

A $5-1000 compressor isn't in the budget.

 

Thats a pretty good idea. I have like a 4.5hp compressor and i cant keep steady pressure. It gets week when i was sandblasting with it. Im gonna go try something like that.

Btw... Go bush man!

 

It takes a special cam to make a mower engine work right as a compressor. Sort of makes it 2 cycle. Way back when they used to make a conversion for the model A 4cylinder. Special cam and air taps into the spark plug hole. On that conversion they only used the center 2 cylinders for pumping air, the outer 2 cylinders they left alone and the thing actually ran on them. Thus it was a gas powered compressor. I've seen one of them in person, but was so long ago I can't remember any more specifics.

If you had a cam that opened the intake every down stroke, and the exhaust every up stroke, then just plumbed into the exhaust port, you'd have a pretty decent compressor. Leaving the cam alone I guess it'd work but only at half efficiency, since it'll only pump air out the exhaust every stroke.

 

OK so mull this over. I yank out the exhaust push rod. then either cut
n re-weld or build up a 2nd lob right across from the stock intake lob
on the cam. That way it can suck on every down stroke.

Long as you have the intake open on every down stroke it should be cool.
No chance of blowing up anything internal from to much pressure. Motor
would be driving from an electric motor with a psi cut off switch.

----------
I just had a look/ There is no way I can cut the lobe off n move it. It
has some pressure reliefe valve pined in the lobe. So I must weld n
build it up . I figure drill some holes and grind it up well. So the new
lobe is pined sort of and not just on top.?

 

I was thinkin bout disabling the exhaust valve too, and using the spark plug hole for the outlet. But then you'd need a check valve on the outlet or it would just suck your air back down and out the intake again. The exhaust port should allready be plumbed for pipe thread anyway, you just need to make the cam work. 2 lobes for each valve, or stay the way it is and work at 1/2 power.

 

umm don;t think you could fill alll them tanks in a day, you may have volume but you may end up with no pressure, that little compressor is probally air cooled non oiled ? it makes alot of noise and little air if its like my crappy craftsman.

in order to store that much air you would have to have more compressors to pump it in. if you want to double volume add another single tank, but going up 2000% will just burn out your motor and compressor.

as for the gas engine how are you going to control pressure. ever hear of a tank exploding it happens all to often and it does kill people. or maybe you;ll get lucky and just be deaf the rest of your days.

look for a deal on a proper sized compressor.. that is what im doing, check with your local air compressor repair companies maybe they have a retired comercial unit that would work for the weekend warrior type.

 

I already have and use all them tanks. It fills them just fine. In under 30 mins 100% EMPTY. It shuts off at 120psi. Been using them forever.
All of my tanks n hoses are rated to 300psi.

---------

I thought about the exhaust valve but there is some over lap in any engine. Its more of a chance it could leak and Ill use the spark plug hole in a 1 way ball check valve.

 

sorry this is a newbie question I have a 5 hp 13 gal compressor, I wish I would have gone bigger but the cost for the time im able to use it didnt seem worth it. anyway can i just put a diect line into a bigger tank to be able to use spray guns and things so my tank isnt kicking on as often?

 

That is exactly why I have so many tanks. I scrapped out 3 compressors for their tanks and then got two 100gal LP tank free from a buddy.

Then two 100gal tanks really boosted my air time. I can go forever without needing air. But when sand blasting I get better results with a higher PSI, why I need more umph. But more tanks is a good way to increase volume easy.

I got the idea from a roofer friend who also bought up broken compressors for their tanks. He had 6-7 10 gal tanks in his truck bed.


http://compressor.8m.com/photo5.html

 

with the setup you currently have what kind of pressure can you get out of it.

 

Moving...