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unloader and bull whip. Howzzat work?

hoary's Avatar

Join Date: Jun 2008
Posts: 103

09-29-12, 10:10 PM   #1  
unloader and bull whip. Howzzat work?

I have a tank and a B&S engine. Planning on making a 'cost reduced' air compressor.

I've had the engine working, compressor works too.
Now I need some way to bring the B&S back to idle when the tank is full.
95-150 Lbs for the tank and compressor.

I'm having trouble 'inventing' an unloader that will bring the B&S to full throttle when the Tank pressure is down to 80# or so.

And when the tank is full enough for the Pop-off valve to open, the throttle on the B&S will drop back to an idle.

I'd sure like a diagram or explanation of the Commercial UN-loaders and the bull whip that handles the throttle on the B&S.

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cheese's Avatar
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Join Date: Jul 2001
Posts: 16,567

09-29-12, 10:41 PM   #2  
Some have a valve that unloads and pushes a throttle cable to control the throttle, and some have a small hose that runs from the unloader to a air-operated piston that controls the throttle. The unloader pops at the set tank pressure and it unloads the valves in the head, letting the valves in the head move a piston that either moves the throttle cable or is piped to the throttle itself where the piston moves the throttle directly.

"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

31YTech's Avatar

Join Date: Feb 2008
Posts: 1,263

09-30-12, 02:10 PM   #3  
Hello hoary,

Here's a short clip on pilot unloaders

Also one on bullwhips

You may be able to get by with just a pilot valve such as THIS with a Bullwhip instead of a full on unloader valve, But I've never tried this.

Good Luck to You !

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