Need some help guys

Scrubcadet10

Moderator
Staff member
Joined
Sep 24, 2017
Threads
250
Messages
6,441
recently acquired a small gas powered air compressor powered by a 6,5hp 126312-0043-B1..
My issue is it immediatly cutting off at idle when the regulator cuts the throttle back. Brand new Briggs and Stratton carburetor, fuel line, cleaned tank, new spark plug. I do not lose spark when this happens. Valves are adjusted to spec. Flywheel key is not sheared.
runs like an ape at full throttle.. just when the regulator puts air to the throttle to idle it down, it'll kill it, which from what i gather, its not supposed to. It does this 8 out of 10 times.
its a coleman powermate CT5590816.02

 

Hammermechanicman

Lawn Addict
Joined
Jan 10, 2020
Threads
56
Messages
3,528
When it cuts back to idle does it unload and vent the compressor output?
 

Scrubcadet10

Moderator
Staff member
Joined
Sep 24, 2017
Threads
250
Messages
6,441
Hmmmmm. I may have been misunderstanding this thing.
When it throttles back at 130PSI the only place air comes from is the line that runs up to the throttle actuator, it does have a larger relief valve on it, and it doesn't let air out at 130psi.
 

Hammermechanicman

Lawn Addict
Joined
Jan 10, 2020
Threads
56
Messages
3,528
Gas powered compressors usually have some type of unloader connected to the throttle control that vents the output of the compressor that is still turning although at a lower speed. If it doesn't vent the head pressure it can kill and idling engine.
 

Scrubcadet10

Moderator
Staff member
Joined
Sep 24, 2017
Threads
250
Messages
6,441
So there's a sticker on the compressor, 10.9cfm at 90 psi, MAX PSI 130psi... looking at the unloader, filled in some engraving on with the paint pen it so i could read it better, the unloader says 175 psi on it.
 

Scrubcadet10

Moderator
Staff member
Joined
Sep 24, 2017
Threads
250
Messages
6,441
36 has been replaced.
20240215-201554.jpg
 
Last edited:

Scrubcadet10

Moderator
Staff member
Joined
Sep 24, 2017
Threads
250
Messages
6,441
what im wondering is if the valve below it is supposed to open up as well?
 

Hammermechanicman

Lawn Addict
Joined
Jan 10, 2020
Threads
56
Messages
3,528
There is usually a vent on the unloader valve that vents at idle.The valve below might be the the over pressure blow off. Not sure where the unload vent is on that one. Have you adjusted the pilot valve?
 

Scrubcadet10

Moderator
Staff member
Joined
Sep 24, 2017
Threads
250
Messages
6,441
There is usually a vent on the unloader valve that vents at idle.The valve below might be the the over pressure blow off. Not sure where the unload vent is on that one. Have you adjusted the pilot valve?
I haven't, I just left as it came out of the box.
Whenever it idles it down it let's a good amount of air out. Just not enough I guess.
 
Top