35 hp 1976 Johnson rough idle to no start

[Kennym2022]

Hey everyone, I’ve got a 1976 35 hp Johnson, and when I got it out this year, I found it had developed a rough idle, but was fine at top end. I cleaned the carb, and reset the points, but after resetting the points to .020, the engine would no longer start, if you crank it, it will sputter and pop, and occasionally back-fire. But won’t start. One of the points was very tight, about .012, the other was about .018. I’m not sure where to go from here. The motor ran the same after the carb clean, but after messing with the points, it won’t start

 

[Crosbyman]

did u switch plug wires ?? post mdl#

 

[Kennym2022]

Did not switch plug wires, though I did move the under flywheel coil by accident

 

[Kennym2022]

Model 35rl76s

 

[Kennym2022]

The motor used to immediately start before I touched the points

 

[Kennym2022]

The motor used to immediately start before I touched the points

Welp, I’m a little retarted I guess. I took the air box off the carb to check something, and figured I’d try starting with the air box off, and it started right up and idles nice. I think the gasket between the carb and air box is torn and was covering the vacuum port on the carb

 

[Crosbyman]

thanks for feedback.. you likely meant the air vent needed to balance
the air volume in the carb. nonetheless it is fixed. good find!
those carbs get their vacum from the crankcase

 

[Kennym2022]

thanks for feedback.. you likely meant the air vent needed to balance
the air volume in the carb. nonetheless it is fixed. good find!
those carbs get their vacum from the crankcase

Yes that’s what I meant, thanks for the help either way

 

[racerone]

Perhaps blocked the vent hole.----That allows atmospheric pressure on fuel in the carburetor bowl.