Bringing Max IV back to life- lack of power issue

[nubs]

I would pull the carb all the way apart and soak it in carb parts cleaner for a day er two when blow out every hole/port with compressed air. the gallon can of cleaner are around 22 bucks but well worth the money.

[Model Citizen]

Whenever I hear of bogging, I think of main jets, but bogging can happen on level ground , too, when you try to give it throttle. And you said that's not happening. You should be able to climb short steep hills barely touching the throttle as long as you hold those sticks forward. Personally, if everything has been cleaned and replaced, as a last resort, I would have MY mechanic drive it up some kind of incline, put it in neutral & rev it to see if anything is obviously different. When you're driving it, you can't see anything going on back there. But that's how a woman thinks.   

[wedge]

 
Check the tank also for stuff choking up the feed line. Did you pull the tube out of the carb body and clean it also ?
Plus the Main jet that is across from the Plug you take out of the carb body on the lower side ?
As WFO said she is Starving for fuel

[WFO]

still could have a carb problem. check your fuel lines, they tend to fall apart inside or shrink causing low fuel flow under load.

[smurfwarrior]

I purchased a Max IV about a week ago and have been working hard to get it back running well.   The previous owner let it sit a year and I've done the following- Removed and replaced fuel with ethanol free fuel, put seafoam in the fuel, replaced the fuel filter, replaced both plugs, replaced the fuel pump, cleaned the interior of the carburetor (it had yellowish film on the bottom), adjusted the idle and tightened the chains.    The clutch belt looks like it working fine, climbs to the top of the top wheel and moves into a tighter radius when the upper moves to a larger radius.

Here's the issue, on flat ground the power is fine, goes about as fast as I'd like it to but as soon as I hit a slight incline (and I hit a ton of those short very steep hills where I hunt) it bogs down and will sometimes die if I don't apply a little choke, and sometimes it dies anyway.   It slows to a crawl, I could walk faster that this can get up those hills.   I have the B&S Vanguard 18hp engine in it.    Am I expecting too much from this?   Should I be able to power up hills or is this normal behavior?     Any hints as to what to try next would be greatly appreciated.