BR550 just won't stop.

PTmowerMech

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Couple of things here.
#1 I'm used to straight two cycles and their quick response time. Pull the trigger and it's wide open in a second or less. This, takes a couple seconds to get up there. What's the way to adjust this. I realize this thing is a beast and has a beast of a fan to get up to speed. So, it's gonna be slower. But adjusting the high (3.25 turns now), doesn't seem to matter after a certain point. Turn it out like 4 turns and it's the same as 3. The low (1.75 turns), It idles OK.

@bertsmobile1 You've helped me a lot with normal 2 cycles. This one's sounds a lot different. Is there anything I need to listen for when adjusting these 4 mix?

#2. When I shut if off at the switch, it idles way down to almost stop. But just keeps trying to stay running. If you have the switch off, it won't start. So the switch has to be good, right? But something is allowing the coil to send juice to the plug? Or could it just be something like a backfire going on that igniting the gas/oil.
I
 

PTmowerMech

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#2 has been solved by adjusting the valves.

But something else I noticed about #1. Nothing changes when I have the low idle screwed all the way in. So, I turned it out to where I got fast response, and unscrewed the idle screw til it was all the way out, and it seemed like it was still idled way too high. But at WOT, it does increase RPM's quite a bit.

Is that normal?
 
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StarTech

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You must use tachometer to make these adjustments. The following a snap shot from the service manual.
BR550 Carb Adjustment.JPG
Note in steps 4 and 5 you tune rich to lower the RPM. Don't tune lean or you risk PNC damage.
 
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