Running again but not getting power

[Jason (IL)]

With the shorter days I can not really mow past 7 here anymore so it has led to some more free time in the shop. I have had this cub sitting there all summer waiting to figure out what is going wrong here. The Cub was running real sluggish, sputtering every time in increased the throttle. I figured dirty carb? Well I did a complete rebuild of it and put it on and found no improvements at all. So I went online and ordered a new carb from Bates Corp. Well that ended with the same result, I needed a Carb for my Demo Cub anyway so nothing lost there. I was confused and took things a little further, I check for vacuum leaks around the manifold and didn't see any at first and then with a second check found a leak on the bottom side behind the carb. Took the manifold off, cleaned it up really good, had to grind a few high spots down, installed new gaskets and put it all back together. I started it up and runs good now.

The cub runs goods drives good but under a load it seems to have little power. I feel the governor is not kicking in when needed. Is there an easy adjustment for this. I am not to familiar with adjusting governors?


Thanks

[Eugene]

Timing light. Check and double check the ignition system. See if the distributor's mechanical advance is working. Search for any other ignition problem.

Ignition system OK, move on to the governor.

[Don McCombs]

When is the last time that the valves were adjusted?

[Steve Butram]

Bring it over to West Lafayette and we can run it on the Dyno

[Scrivet]

......... The cub runs goods drives good but under a load it seems to have little power. I feel the governor is not kicking in when needed...........

Little power could be the valves or timing as has been mentioned. Make sure those are both correct.

As far as "governor not kicking in", before tearing into the governor, make sure there is NO movement between the governor rockshaft (from the carb) and the governor rockshaft spring lever. Shine a bright light in there and move the lever where the carb rod attaches. If they don't move as one piece you need to fix it. The whole thing works on about 5 degrees of movement. 1 degree of slop is a 20 percent loss of movement and delays the governors reaction if it can react at all by then.