G16 Cart Not shifting Governor / clutch issue

[DEERSLAYER81]

Hello everyone, First off Im new to this but have used the site for years and have used preious members posts to help in many trouble shooting instances. You folks are very helpful and I thank you in advance for your help. Im at my ends wit here, out of ideas and patience. Im having some type of clutch or governor issue. To make a long storty short the cart wont down shift or the clutches wont "hold" or "open" up under load. In nuetral or on jack stands the clutches operate perfectly... no issues at all they open up and close as they should. Under a load (drove around with the seat off) the belts kinda sits in the middle the clutches wont open up all the way and the belt wont drop down. Heres what ive done already.

-one primary clutch weight and roller replaced (one was wore and stuck -flat spot)
-tore down the primary replaced the seals and bushings cleaned it extensively lubed with a dry lube(the original seals and bushings were wasted) the previous owner must have put an entire tube of grease in it.) you can eat off of it now
-new belt
-new secondary clutch spring and inner sheave along with rear bushings and seals
-secondary spring was set in the stock position and set with a 1/3rd turn in
-new rear ramp shoes (they are touching the ramp(s) and ride on them nicely)
-new plug
-new fuel filter
-new air filter
-engine has 148 lbs of compression
-new valve seals
In addition the motor is a little smokey but not bad. Ive had them way worse in the past (crop dusters) and they still got up and went. I can push it around in nuetral with no issues its nice and smooth its not being held up by something. Also the governor shaft is a little loose in the rear end...the bushing/seal must be going it still apears to operate fine just a little loose. Ive also watched the butterfly on the carb it opens all the way. Also under a load (driving) the last half of the gas pedal doesnt seem to do much it acts like it wants to go but just as it should start to shift it hangs up. like i said in nuetral or on jack stands it revs right up and the clutches work great. Drive it around on the yard and its a slug. However it is much better on my concrete driveway though. Please help like i said im out of ideas...hit a brick wall! Thanks everyone I really appreciate it. I look forward to your ideas.

[LURCH]

Call Don @ Plowmans sounds like you still have clutch problems.

[DEERSLAYER81]

Thanks, I will.

[Mchalin]

one odd ball thing on the driven clutch is u have to grease that zerg fitting or the brass bushing inside goes to hell and the sheeve will wobble on the shaft. Ive seen them jamm up when you buy the kits they NEVER tell you that. if you hit water alot use water proof snyth grease.

[DEERSLAYER81]

FIXED IT....YOU'll NEVER GUESS WHAT IT WAS...A PLUGGED UP MUFFLER!!! I PULLED THE MUFFLER OFF AND COULD BARELY BLOW THROUGH IT. I HAD ANOTHER CART AND SWAPPED MUFFLERS. SHE RUNS LIKE A CHAMP NOW!!!