20 hp lawn tractor will not pull?

[accordionman]

HELLO TO ALL,
i have a friend that has a 20 hp lawn tractor.
he also has a leaf vacuum, and says the tractor
is having trouble pulling it. says the engine is
going up, and down in speed, and does this all
the time. ask me about it, and i said, it sounds
like the govenor is "HUNTING" trying to find an
rpm to settle on. ask me what would cause this,
i said, i am not sure, unless the carb needs to
be adjusted.
any comments, please.
accordionman
wlbrown
wright city, mo.

 

[mark1]

Hi..You didn't give us much to go on.Like what make,engine,age,gas or diesel, so we'll make some assumptions. first a 20 Hp machine should have no problems pulling things like a lawn vac.
Has it ever had a "real" tuneup? plugs,POINTS,condenser?a bad set of points will make these engines run terrible,
how old is the fuel. does he get black exhaust.ever changed the air filter? /forums/images/graemlins/confused.gif

 

[billbill1]

The carb could be dirty or it could be a simple adjustment of the gas valve on the bottom of the carb. Try turning the valve open a little bit at a time and see if it improves. Turn the valve in or out until the engine smooths out.

 

[OrangeGuy]

Sounds like a gas engine that sat over the winter with old gas in it. Carb may need to be disassembled and cleaned. At the very least the old gas has to be drained out and fresh gas put in. How do I know? My gas powered generator ran as you described. Had to remove carb, clean and put in new gas. Now runs like new.

OrangeGuy