Lawn Boy expert needed...

I have wanted to add a Lawn Boy to my fleet for sometime. A buddy at work called me and asked if I would be interested in this unit. It was his father's. I said yes without even doing any research. He says it starts first pull and works well. He has the service manual and owner's manual as well as the bag and plug. Anyways, I cannot pick it up for a few days and I am wondering what model it is and looking for some expert opinions on if it is a good grab. He has no further info than these two pictures.

Anything specific I should check when checking it out?

https://www.flickr.com/photos/150188168@N02/shares/4v630J

Hi Andrew,

Hmmm a Lawn-boy expert I'm not, but here is my advice. It's a F engine commercial, sorry don't know the model number. Keep in mind most commercial L.B.'s were used commercially, and have many hours on them, but some guys did buy the commercial ones and just used them on their own property.

One thing I check before buying any used mower is crankshaft end play. Any play indicates the bearings are worn and would need a rebuild. Simple to check, just try to wiggle the crankshaft (blade end) side to side and lengthwise. There should be little to no play when you check this. Another item to check is crankcase seals. You can check these by starting the engine, letting it run for a few minutes, then shut it off then try to restart. If it's hard to restart when hot, the crankcase seals are likely worn (leaking).

As far as how much to pay, I've never spent more than 110.00 on a used mower. Craigslist, garage sales and curb finds are all good places to look for a used L.B.

F engines run great (some say the best engine L.B. made and I wouldn't argue with that) , but the parts are getting harder to find. Duraforce engines have their quirks but are a beast when it comes to power, and parts are readily available.

Regards

Jeff

that particular f series industrial was used on quite few, it was even used by john deere on one of there commercial push mowers!

Brings back lots of memories. I worked for Lawnboy headquarters in Memphis Tn from 1985 to 1988, a total of 3 1/2 years in the engineering dept. I was in the advanced projects group working on future designs. The top mount starter system that came out in 1987 is my only claim to Lawnboy fame. That's a great mower you are looking at if it has been maintained. You have a commercial series mower from about 1980 maybe model # 6300. The only difference in a residential and commercial mower is cosmetic and a few added features. The F engine in all lawnboys is virtually the same with some differences if it is self propelled or not. The first issue that usually arises is the exhaust ports will begin
to carbon build-up and the engine will lose power. Easy fix, just turn it over and remove the muffler and clean out the ports and muffler. If you do remove the muffler make sure to center the little bracket/crankshaft support around the crank. Crankshaft seals do fail occasionally but are easily replaced. Biggest enemy is dirt ingestion from air cleaner. This will wear out the rings and the crank bearings. If the air filter was keep clean and proper oil/fuel mix used these things will run forever. Added features to the commercial are things like the larger fuel tank for longer run time, steel wheels with bearings. engine guard( the carb is exposed somewhat and can be damaged from pushing it under things). Looks like the on/off switch is broken but may still function . The primer bulb is showing it's age too and will probably crack and fail. Hard to cold start without it. Thanks for sharing. Lawnboy bought Gilson in 1988 and headquarters was closed and moved to Wisconsin. Then the next year they were bought by Toro. I didn't want to go north so I was laid off. Man that was a long post. I have a couple of these mowers from the 80's and still use them. People give them to me and I get them running. Ignition/coils are prone to failure also. no spark and its done. Oh yea , we made the John Deere walk behind mowers around the mid 80's to. All Lawnmowers were assembled in Sardis , Miss. and the f-engines were machined and assembled in Oxford, Miss. Go Ole Miss!