Low speed jet adjustment

I have recently rebuilt my carbs on a 1993 70hp Johnson.. last season I could not keep the motor running at idle. It ran beautifully at anything over idle. But at idle it would start to shake for a couple seconds do a small cough and stall.
Low speed jet adjustment is what I’m concluding.
My question is, when starting the sync procedure it says seat gently.. does this mean spring compressed till you feel a bit of resistance. The spring is not a very stiff spring so it doesn’t take much to compress it.
I have checked all gas lines for cracks, they all look like new. No backflow at the fuel bulb. Everything thing else with the motor is amazingly clean. Except the plugs, they get pretty black. I run premixed 50-1. VRO was deleted before I got the motor. I only run Penzzoil XLF 2 stroke oil..

This process starts with a compression test.----Post your actual values.----There have been issues with # 2 cylinder.-----And does the telltale hose come off the exhaust manifold ( side off the block ) , or moved to the top of the block?

racerone said:

This process starts with a compression test.----Post your actual values.----There have been issues with # 2 cylinder.-----And does the telltale hose come off the exhaust manifold ( side off the block ) , or moved to the top of the block?

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compression 120-119-120 telltale hose moved to the top. just need to know if you screw the low speed jet all the way in compressing the spring then bring it out 1 1/2 turns to start with. my low speed jet comes off the side of the carb(#15&23 in pic) not in the front,so spring is on the outside of the carb.

seat the needle all the way in counting turns as you shut it down... don'T worry about the spring

remove the needle and spring and blast the internal orifice (passage way) with carb cleaner and a blast of air do it twice just in case.... wear safety glasses while doing so

reinstall the needle and spring and reseat completely... as you did in step 1
unscrew the needle with the same amount of turns you had when you seated the needle closed.

see if idle improves and adjust

Have you balanced the carbs....so all three are opening at the same time. If you have one carb opening before or after the others you wont get a nice idle .