G1 RPM drop-no response to throttle

[TexTurbo]

I'm usually in the Electric side, so if you see a tall bald guy wandering around smelling like 2 cycle exhaust, that's me !!!
A "new to me" 84, G1. Has been running well, but developed an intermittent problem I cant seem to resolve.
Starts and runs well in both directions, but will all of a sudden lose engine RPM down to just above idle and just below clutch engagement.
Trying more accelerator only make a very slight different sound in intake noise, but no increase in RPM.
This condition will stay that way through trying forward or reverse and may last a few minutes and then clear up for a few days.
I have had it happen 2 or 3 times in just a run around the neighborhood.

Things I have done so far:
Rebuild carb (including tanking in cleaner and clearing all jets and passages.)
Spark plug
verify fuel pump flow to carb when problem is happening
All carb and governor related linkages, springs, and actuators are tight and moving freely.

Any ideas ??
Thanks !!!!

[slonomo]

First thing that comes to my mind is fuel supply. I would check and replace all the rubber fuel lines including the vacuum pulse line.

On the G1, the fuel pickup tube inside the tank is known to develop cracks and cause this problem. Last time I checked the part is still available, but on mine I just used rubber fuel line inside the tank and made sure it was hanging all the way down to the bottom.

[AUTOMAN]

Is the throttle opening?

[TexTurbo]

DING DING DING !!!! We have a winner !!

SLONOMO....... a crack in the fuel pump "vacuum pulse" line !!!

****, that thing is hard to get to !! While I was at it, replaced ALL the old rubber fuel/Vac lines... Runs like a top !!

Thanks !!!!

[slonomo]

Glad you got it figured out!