Gov: From what I can see there seems to be a real issue with the Newer LB Units. Either the Epa or Ethanol Base Fuels seem to wreak havoc with these mowers. Usually small engines prefer lower grade gasoline. Higher Octane does nothing for them since they are (4-Stroke) rather low compression engines. The Older 2-Stroke Units could benefit from the increased volatility of 93 or perhaps Av-Gas but not the Newer Engines , just a waste of Your $$$ . As far as re-jetting yes certain models of the newer LB units can really benefit from some re-tuning , if you are knowledgeable within Carburetor Rebuilding . If your are a Novice I would rethink that Option. If you are really serious then spend a few $$ and have some fun and invest some time in refurbishing your mower . 1st check out the compression to justify this work and go for it . There are more than s few LB Enthusiasts on this forum who would probably be more than interested in giving you more information (Pro's & Con's) of your Indicated Model .

I'm not an expert but I have a 10323, purchased new in '03 (same engine as yours). Great mowers but they can be finicky and require a bit more maintenance and knowledge to keep'em going.

Spark- The ignition coils in these fail often (p/n 99-2911), check ebay. Distance between the coil and the embedded flywheel magnets should be .010" (use a new business card). Probably wouldn't hurt to throw a new plug in it too, (NGK BPMR4A). On these no starts, be sure to check the ground wire to see if it's grounding out when it shouldn't (it hooks to that bracket on the side of the engine that moves when you pull in the bail). Use a multimeter set to "ohms".

Fuel- The shutoff is a good idea, I'm adding one to my mower. I would run a mid-grade fuel (89), the good 'ol Lawnboy oil 32:1. And some guys like to add 1 oz./gallon of MMO also. Always run fresh potent fuel, mix just enough to make it 30 days or so before having to fill your gas can back up.

Surging- If it had been fine for a long time, then started surging, I guess I would pull the carb loose and clean the jet holes with a small guage copper wire or something. And of course check the float bowl, screen, etc. Loose mounting bolts (those 2 long ones holding everything together) can cause an air leak which will make it surge. But too tight is bad too as it causes binding. People have success re-jetting the carb, lots of info here, just use the search. Not sure about a rebuild kit, maybe you can just get the old one nice and clean?

2 other things-

1. Clean the carbon build up out of the exhaust ports. You don't want any restriction here. Use an Oak dowel or something so that you don't scratch anything.

2. Tip the mower up and look underneath where the crankshaft comes out, see if it's wet and oily. If so, the lower crank seal is leaking and should be replaced. My mower has this problem, and is very hard to start at times. I hope to make it through the rest of the season and replace it this winter. These 2 strokes rely on that vacuum and pressure to move the fuel mix properly.

Hope this helps...

Lots of opinions, so I'll offer mine. First, the surging is a fuel metering effect and has nothing to do with the ignition. Since your mower is basically starting when you want it to, the CD pack (coil) at least is functioning but might be starting to weaken. It is common on the later LBs to have to replace the coil every few years.
Does the engine surge when under a load when actually mowing? If so, it is running too lean and has to be fixed. If it just surges when not mowing, no repair is indicated, but metering jet enlargement would still provide smoother running.
The assumption here is that you are moving the throttle lever, right after starting, off the 'choke' position and into the full-speed position, and that you might play around with it some to make sure it's off 'choke' and as high as it can get without going into 'choke'.
Surging is a very predictable and 'normal' effect on these engines because they are leaned-out from the factory to meet EPA requirements. However, the normal enriching under load usually smooths it out.
87 octane is the minimum acceptable fuel. I prefer mid-grade (or half regular, half premium) because the fuel loses volatiles in the can (when you open it on a hot day, the vapors shooting out are the good stuff) and to a greater extent in the vented mower fuel tank. With mid-grade, you stand a better chance of retaining the minimum octane for the duration of the fuel.
Additives: I use the following in my 2-cycle tools and also used it in my 2-cycle LBs when I had them, two of which had the Duraforce engine: At least 1 oz/gal of Marvel Mystery Oil in addition to the regular mix oil (up to 4oz/gal is okay), and 1/2 oz/2 gal of Sta-Bil 'Marine' stabilizer/cleaner for Ethanol-blended fuels. This is good whether or not you use alky fuels.
Use of governor adjustment to mitigate surging: this has been effective for many owners. First, you have to determine if the air vane moves freely and snaps back when released. With engine off, remove air filter and observe throttle plate in carb in the wide-open position. Push air vane over and release to see that it snaps back to wide open. You should have a tachometer for this but you can make a small adjustment without it. Reach to the base of the air vane and find the round knurled disk at it's base - this is the governor tension preset. Give it four clicks clockwise. Replace filter and cover and start engine - use the mower to mow for at least five minutes. Evaluate engine speed and performance, including idle speed, to see if further increase in tension is warranted. The engine will increase RPM as the disc is turned clockwise and decrease with counter-clockwise turning. You don't want to over-speed the engine, but I don't think it's within the range of the preset to do so - you probably will only get 500 or more RPM max.
Many, if not most, of these mowers apparently came from the factory with unusually low engine speeds, which tends to magnify the surging problem. I have also personally observed several owners who did not know to pull the throttle lever off 'choke' after starting, which really screws up the mowing experience - if you're getting clouds of smoke, heed this.

I have used Lawn boys all my life (started in the late 70s) and none have been like this one. I assumed that Commercial grade meant that it was the real deal. Not finicky....

Spark: I will check the ground with a meter and if needs be get a new coil. When the next issue of the no-start happens I will report back.

Fuel: Brand new 87 octane with a product called FA (fuel activiator) and LB 32:1. The FA has been used with no surging and with surging so it stands to reason that it is the carb. MMO will be another pick-up soon. I also have Startron's marine stabilizer for my jet ski. I will apply some of that.

I have very little experience with cleaning carbs, or re-jetting them for that matter. If I fail I will get a new one. They are $70 or so now on LB's site. I will go try that as well.

I will report back when I have some news. Thank you for the information.

Lots of good info here. The Dura Force carb is very lean from the factory. It must be CLEAN to run right. Make sure that the pilot jet orifices are clean. The pilot jet is located under a sticker on the left side of the carb. No need to remove the carb to get to it. Also, this is the jet you want to start with if you go with a larger size. One, because it will usually solve the surge problem and 2, because you can buy size 40 and 42 jets that just screw right in. The main jet must be drilled to increase it's size. If you are used to the older Lawnboys then the E series engine can try your patience. Use the MMO that Saxman recommended. Seafoam is also a good item to use in your fuel to keep your carb clean. Keep us informed.

Old carb number was 98-7042. Here's one on ebay.

New number for that carb is 1074607. Runs about $55.

Here is a link that might be useful: DF carb

Much has been done. I purchased a number of parts to rebuild the carb but only used the new float, needle valve, and valve seat. I re-used the same jets and drilled them out to what was said in a number of posts. I had issues with the speed of the engine so I purchased the Briggs and Straton tachometer to dial in my engine speed. The fuel filter is in place and the mower is working amazingly. My dad has a 10525 and it too is surging like a champ. That is next on my list. The lack of spark has yet to re-surface and when it does I will check back in. Thank you to all for your help.

I drilled out the jets on my dad's 10525. the pilot with a #78 and the main with the #67. The mower blows major smoke now which is making me think I might have oversized the jets. I have spare jets for both the pilot and main jets. Should I swap out the main back to a regular size or the pilot back to a regular size? Opinions??? Thank you.

Do not use the visible smoke you see as an indicator of the proper fuel/air ratio your carb is producing. The best indicator for someone without test equipment is your hearing. When mowing in little or no grass the mower should have a slight burble sound as opposed to a smooth hum. When encountering a heavy mowing load the governor will add throttle causing the burble to convert to a smooth hum until the governor backs the throttle down in response to a lighter load. It is true that a richer fuel mixture can cause more smoke but that is not an accurate way to set carburetor mixtures. Too many other variables involved.

That's right - could be just too much oil in the gas. But, you may have reamed out the jets too much.

I swapped the reamed main jet out for a stock main jet and it purrs perfectly. Thank you again!