I have a Lawnboy 8237 that runs painfully slow. I've skimmed the manual, and all I see is an "altitude adjustment" screw. Is adjusting that the only way I can increase the running speed? (Yes, it has a "light/normal" speed lever, and that doesn't resolve the issue.)
#2
2smoked
Based on my experience, a muffler that is choked with carbon can cause slow, sluggish performance. Remove the blade and the blade collar, then remove the muffler. Shake it a little bit to see if there are bigger carbon chunks floating around. As long as you have it off, check the exhaust ports on the cylinder and see if they are blocked with carbon. The next step I would take is to see if the air van governor is operating freely. It might need some adjustment to the spring tension. Sometimes I have removed the whole carb and have found that the tension spring has been installed improperly or the adjustment collar is set wrong. You will need a service manual to walk you through the proper steps. If you do not have a manual, there may be another member here who can direct you to one that can be downloaded.
Don’t give up. Your model has an F engine with a simple air vane governor, which I feel was Lawn Boys’ best design. When an older Lawn Boy does not run properly, it’s usually a small problem. The 2 cycle engine is very basic and with time and patience, most running problems can be easily solved.
Attachments
#3
2smoked
I failed to mention to begin with something simple and check that the air filter is not full of dirt.
#4
Teds
Assuming the other common bugaboos mentioned have been checked and found OK or remedied e.g. exhaust restriction or clogged air filter element &c., you'll need a small engine digital tachometer and get in the manual to familiarize yourself with the governor setup and adjustment. "NORMAL" setting is spec'd @ 3100-3300 RPM.
To take it a bit farther, to the next level ensure first verify that the blade itself is both balanced and straight, and clocked on the crankshaft correctly, also check that the blade tracking in the deck is in spec. Various thickness shims (washers) can be placed between muffler housing and deck if required. An out of balance condition increases power robbing vibration levels noticeably and reduces the quality of the cut. A sharp balanced blade running at the correct RPM is what makes them work as advertised.
