My 2 stroke Lawnboy lives Some old tricks. Make a sandwich + a drink

[andyd]

It is a 1988 21" F series engine, model 7073. I snagged it off Craigslist free stuff back in '07. A steel deck, nothing fancy. Great trimmer. I used it until the starter spring broke. then parked it' Back in '17, I cleaned up the coil, the carb and governor. I use an old 1/2" drill with a 11'16 deep socket to spin it over. Ran great the last time I used it.
Yesterday, dug it out after a 3 yr hiatus. I used some 2 week old mix and B 12 Chem-tool. Several tries starting before it lit and over revved the drill. I lifted the drill and the crank nut dropped into the fan. Then, TING and it went who knows where. Meantime, sans nut, the engine burbled along merrily. I had a parts mower for another nut, but that was enough for the day. Today, I pulled the plug and pushed a couple feet of rope into the cylinder to lock the crank shaft. The old rope trick. I tightened up the new nut with a 2' cheater on the ratchet. That done, the errant nut caught my eye.lying on the ground beside the mower. A good omen.But I wasn't gonna push my luck. I had another old trick to use. With a prick punch. I staked the junction of the top turn of thread between nut and shaft. About 20 dimples around. Back again from the pre-nylok days. The B 12 worked its magic and miracle of miracles, the primer button works too. I let it idle until it ran out of gas, so I could sharpen the blade. Another trick, suggested by BIL. My 4" HF grinder, don't even take it off, lay the wheel against the blade matching the existing angle.

 

[Wrenchturner44]

Hang on to that LB. I miss mine. The last year models are getting harder to find. Be where though if someone from the EPA stops at your house and asks if you own.......LOL.

 

[daves87rs]

Very nice!

 

[skyactiv]

I bought a Duraforce 2-stroke Lawn-Boy the last year they made them when I got my first house as a young home owner. I spoke of it here recently. I recently gave it to my dad as he no longer wants to pay to have the grass cut at his summer house. @$50 a pop.

I quite using the mower in 2017 when I moved to acreage. I never used it as a trim mower. He mowed the lawn once and decided to buy a Toro Super Recycler with the 190cc engine.

The Lawn-Boy is light and has lots of power. The Duraforce is 140cc's. I did put a put a new coil and carb on it. BTW, my LB came new with an NGK plug, but the better Champion spark plug with the thinner wire, not the basic cheap one, the EZ start one or whatever they renamed it now, last longer than the NGK.

The staggered wheels allowed me to get close to plants and things which made less work when using a weed trimmer.

I used SuperTech outboard 2-stroke @32:1 for years in it.

You stink after mowing with a 2-stroke Lawn-Boy.

The Duraforce engine is bigger with higher compression than the prior F series engine.

I think I paid $279 for the mower @ Meijer in 2003.

My dad loves his new mower. https://www.acehardware.com/departments/lawn-and-garden/lawn-mowers/push-mowers/7026287

 

[bunnspecial]

Thanks for the write up on this.

I grew up using 2-stroke Lawn Boys, and a search last year led to me buying two late ones from a member here local to me.

I've since become...well maybe a bit of a collector with more than a few. The main one I've been using this year is a 7262, a D600 engine mower from 1973. With that said, life has gotten in the way this week and it's been a week and a half since I mowed, so I'm probably going to pull out a Duraforce to use today. The pre-compliance mowers all top out at 3" where later ones will go to 3 1/2. Mulching is probably out of the question today, but if I wanted to a Duraforce would probably be my only hope to get it done.

On any of them, don't forget to clean the exhaust ports as part of your routine maintenance. How dirty they get of course depends a lot on what oil you're using for oil(and yes, ashless TC-W3 is fine). Still, though, blocked up exhaust can cause issues and hard carbon around the ports can scratch your piston. Past the ports be sure you get the muffler clean also. I've bought a few that likely haven't been touched in years if ever, and had so much carbon built up in the passages of the muffler that it's a wonder anything could flow through it. A paint scraper works well. I've talked to some who will toss the whole thing on a gas grill for an hour or two and that will get the muffler actually truly clean.

I started to say that the springs were easy to find and replace as well as inexpensive, but I forgot that the later F engines used a top mount starter. It doesn't look like the spring can be replaced on it separate from the whole assembly as on the side-mount style, and the parts are pricey. That's a shame. The early kind is a little intimidating the first time you do one(the spring packs a punch once you cut the keepers loose) and can seem like it needs 3 hands until you get the hang of it, but at the end of the day replacing isn't a big deal and it's a $10 part.

 

[RaymondP]

Like 2-stroke motorcycle, seem to be becoming a rarity. Sadly, will have to give up mine as the deck is severely rusted through making it dangerous. Engine runs fine! Another testimony to the old tried and trusted, although recognize, as with any two-stroke, it is not the cleanest of operating motors.

 

[bunnspecial]

Like 2-stroke motorcycle, seem to be becoming a rarity. Sadly, will have to give up mine as the deck is severely rusted through making it dangerous. Engine runs fine! Another testimony to the old tried and trusted, although recognize, as with any two-stroke, it is not the cleanest of operating motors.

Look for an alloy deck with a trashed engine.

AFAIK, every basic engine(except maybe the V engine, but don't hold me to that) had an alloy deck counterpart. Not only are the alloy decks lighter, but they also don't rust. They can crack, but if you're so inclined they're generally straight forward to weld. I'm no welder, but I have one with an ugly but functional patch(cosmetic, not directly in the blade path) that I TIG welded on.

BTW, just finished mowing with a 10547 from 1998. That's a Duraforce powered alloy deck mower with the 3-speed transmission and electric start. It fought be a bit to start and then restart warm, but hopefully a tune-up/clean-up will fix that. We'll see. I tried to get the electric start going the other day with a bench power supply and got nothing, but it hit me while using it that there's probably a lockout on the kill bar also. With as touch as it is to start, electric start would be nice but I also don't want to pay $100 for a battery.

 

[FADEC]

It is a 1988 21" F series engine, model 7073. I snagged it off Craigslist free stuff back in '07. A steel deck, nothing fancy. Great trimmer. I used it until the starter spring broke. then parked it' Back in '17, I cleaned up the coil, the carb and governor. I use an old 1/2" drill with a 11'16 deep socket to spin it over. Ran great the last time I used it.
Yesterday, dug it out after a 3 yr hiatus. I used some 2 week old mix and B 12 Chem-tool. Several tries starting before it lit and over revved the drill. I lifted the drill and the crank nut dropped into the fan. Then, TING and it went who knows where. Meantime, sans nut, the engine burbled along merrily. I had a parts mower for another nut, but that was enough for the day. Today, I pulled the plug and pushed a couple feet of rope into the cylinder to lock the crank shaft. The old rope trick. I tightened up the new nut with a 2' cheater on the ratchet. That done, the errant nut caught my eye.lying on the ground beside the mower. A good omen.But I wasn't gonna push my luck. I had another old trick to use. With a prick punch. I staked the junction of the top turn of thread between nut and shaft. About 20 dimples around. Back again from the pre-nylok days. The B 12 worked its magic and miracle of miracles, the primer button works too. I let it idle until it ran out of gas, so I could sharpen the blade. Another trick, suggested by BIL. My 4" HF grinder, don't even take it off, lay the wheel against the blade matching the existing angle.

This is my push mower that I have used since the early 90's. Runs strong.

 

[super20dan]

i would still be using lawnboys if not for the staggered wheel deck . it adds too much time and extra trimming in commercial use. the staggered deck also stinks when mowing hills and ditches and spetic tank mounds. also much eaiser to scalp