Old LawnBoy 2 Stroke Mower Wont Start - Lets Fix It

LawnBoy 2 Stroke Mower
A really Nice Older Machine but its Cranky.
Lets see if I can get it running again

[@notajp]

The ones with the muffler above the deck are Duraforce engines. The one with the muffler under the deck has an F series engine.

[@TheNovaJohn]

Thanks! I like the idea of the muffler underneath!

[@larrycroft470]

I like Lawn Boys Arch!! You gave that one a new lease on life!

[@TheNovaJohn]

This was a fun one,,,stay tuned, another is coming soon!

[@brucecoleman7412]

On 2 stroke Lawnboys, the factory recommends indexing the blade. First set the engine to TDC. Then the blade should be installed 90 degrees to the cylinder axis. I’m not sure why they said to do that unless it’s to reduce vibration. I had one in the 60s with a goldish colored deck before they made everything green.

[@TheNovaJohn]

wow,,, I know of those old models, very nice! Yes, it reduces vibration and reduces stress on the bearings. Not a bad idea. Keep in mind stresses are different on 2 strokes. they fire twice instead of once for 4 strokes. Engines can be neutral, overbalanced or underbalanced. 4 strokes can be more neutral because they have to spin for 3 strokes before they get powered. In other words 2 smokers bang more often.

[@johnforsyth8414]

Why is TDC?

[@brucecoleman7412]

@@johnforsyth8414 Top Dead Center to keep the blade in balance when the spark plug fires.

[@johnforsyth8414]

@@brucecoleman7412 Specifically, how do I accomplish that? Piston closed? Or something else?

[@johnforsyth8414]

@@brucecoleman7412 How exactly is that done? The piston is closed at the muffler? Can you elaborate? Thanks

[@garymarkham4167]

Nice job mate...Do they still make Lawnboy mowers in the US.....? Cheers from Australia.

[@TheNovaJohn]

Australia IN DA House! lol Ohh they stopped making these long ago but did continue with a newer design up to fairly recently,,not sure when, somewhere in the 2000's Thanx for watchin!

[@TickenLifters]

I found one with a cracked fly wheel what do you think caused it is the motor itself bad iv never saw a cracked fly wheel tho im used to briggs and are they Tecumseh motors

[@TheNovaJohn]

must of hit something is my guess, depends on where the crack is

[@jeremycook5943]

What ended up being the fuel issue? Because I’m working on a very similar model now and it’s not getting proper fuel. It runs great on starter fluid but shuts off when that runs out.

[@TheNovaJohn]

Starting at 9:03 I found a small crack on the fuel line, dirt in the tank filter, I adjusted the fuel jet screw and something isn't right with the fuel shut off valve. Also check your tank cap lemme know how ya make out!! Thanks for watching, this is one of my 1st videos, sorry for the unclear info

[@jeremycook5943]

No worries, it’s a well done video! I’m going to give these things a shot and let ya know. Appreciate the response!

[@Dartht33bagger]

Clean the fuel tank, new fuel lines, rebuild the carb and then set the jetting. That would cover all possible fueling issues.

[@johnforsyth8414]

Are those lawnboy 2 stroke foam air filters supposed to be oiled or not?

[@TheNovaJohn]

Most people insist on it.. I know the briggs say it. I use WD-40 If your area is dusty then a light motor oil is better but squeeze all of it out. There are new products out for air filters you may want to look for. My guess is, if it isn't gonna see a lot of dust, it doesn't matter.

[@buddylove4882]

Well done.Well done mate.

[@TheNovaJohn]

Thanx Buddy!! There is a new one out now! That's much older video!

[@johnforsyth8414]

What was in that bottle that you put into the cylinder? I have the same mower. It started on the second or third pull for years. I just replaced the muffler and put the blade mount and blade back on. Can’t get it to start! Replaced with new plug. Still nothing. Any advice?

[@TheNovaJohn]

Thats an old video now, without watching it again, probably 2 stroke or my transmission fluid mix. Hard to say what your issues is, why did you replace the muffler? Maybe you disturbed something in the process. My guess is you may have dislodge some junk in the tank or carb Its back to the basics, check spark, and fuel

[@johnforsyth8414]

@@TheNovaJohn The original muffler lasted @ 35 years. I put another one on 2 years ago. F type muffler. The tube came out and hit the blade. Thought it was an OEM muffler but eBay you never know. Just bought another one and put it in. Took a long time but eventually started. I’m going to remove the carb and clean everything out. Also going to replace the primer bulb hose. Looks old & stiff. The ignition coil is the original one I read somewhere that they may not be working at optimal performance. Is there any truth to that? I can get a replacement coil for about 20 bucks. Not sure if I should do it or not? Please let me know. Thanks!

[@TheNovaJohn]

Great story,,,I like the back stories on these old ,machines! Coils can wear, usually I just clean them and the flywheel and re-gap Try an aftermarket coil and keep the old one perhaps just in case. I have seen situations where aftermarket coils arent timed right, wont work, will spark but just wont fire. I think it would be nice to go over this machine fully and then you have it again for a very long time!

[@theduogamingchannel1263]

I have a mower like that pulls kinda hard with plug out shredded rope replaced and same thing could this be bad rings

[@TheNovaJohn]

is it pulling hard because the rope/starter is messed up? That would be the 1st thing I would fix Do a compression test if you have the tool Take some penetrating fluid and spray it into the plug hole after you fix the rope starter and see if it loosens up. Often the oil/fuel mix will varnish up and make things very sticky. This will help to free it up. You could spray carb cleaner in 1st, pull it a bunch of times then spray lube into the hole and repeat and see what happens!

[@hiphopman72]

Got one of those

[@piotrszelag75]

Hi. I write from Poland. Would you tell me, what is the number of model of this LawnBoy? Because i can't find it on google😣. I buy this mower in Szczecin and i know its rarity. I would like to know in which year it was produced

[@TheNovaJohn]

I don't know, it sold and this was at least 2 years ago. One of my 1st videos! Typically, these were made in the early1980's or very late 70's. There should be a tag or name plate on it somewhere. Glad to Hear Poland is in the house! Good luck this winter, many of us here in the U.S, are thinkin of everyone over there despite what you may hear from our Gov.

[@jonnysnipes3123]

7035 I believe. It looks like a 1988 model

[@crisprtalk6963]

These must be the all terrain tires.

[@TheNovaJohn]

These are the second best type. The orange ones on the one I own are steel with grease fittings for the older commercial machines

[@crisprtalk6963]

Every 2 stroke video on youtube.... pull the cord twenty times and maybe it will start, maybe not.

[@TheNovaJohn]

This one hadn't run in a long time!! 2 strokes need more compression than 4 strokes, I like at least $100psi...

[@stevesmith6058]

You never shave the ends of a blade it’s an improper way of sharpening it or or balance it out rather you takeoff material on top of the blade sharpening

[@TheNovaJohn]

That's not what I did, I shortened the blade, equally, from the center. watch it again. Then I balanced it and it ran true without any vibration.

[@pattayperformance]

Wait...what was the fix for the fuel issue? I have one of these form my scrap guy for $5 no bag! I thought 2 stroke mowers go for big bucks...GRRRR Whats with those snow blowers?

[@TheNovaJohn]

It was cranky,,, if you've noticed which I know you have as you work on smaller 2 smokers, they just wont run if the fuel mix isn't really close! Weedwackers often wont even run or start if the mixture screws aren't really close. That's the 1st issue; in a wacker engine, the diaphragms (top & bottom) are the reed valves, they are small flaps, they are the valves, in the larger motor, those valves are further in the engine, I didn't take these off, I avoided it, some engines you can take them off and flip them so the slight bend will force the reeds closed,.(they are spring steel, if the motor overheats they loose temper; wear can make them come off their seat as well). That said, often dirt/carbon will keep them open slightly, this is why I use my "Special Sauce" during the early stages of repair/diagnoses. (compression test wont show this) also 2 smoke fuel will gool up rings and other parts, it makes a kind of tar & varnish so a good cleaning is in order. Making sure the float is high enough to present good flow, these engines are really sensitive to all these issues, once you get it to run you can adjust the mixture screws, this one has one on the side of the carb, the last person cranked it in to 1/2 turn.. I wasn't planning on doing a video on this one, its been sitting and I figured if I didn't do it now, it would sit. I don't think they are worth much, it depends on the model, I have another that is the commercial version, that is worth a little more but I would like to keep it. I have offers to rebuild and restore existing machines that a few people have, people do collect these. I have an old friend from out of state that just got one from 1959!! They were really good machines, light, strong, they run on clean gas and oil unlike 4 strokes that sit in the crankcase as you know,,,!!!

[@hiphopman72]

@@TheNovaJohn i like sauce and my 2 stroke is flemsy to start ... can you help a brother with the special sauce 😀