You got yerself a "squirter" huh Steve??!! Man, I can't go there with that! Anyway, there should be a felt gasket with a small hole underneath the cap that should eliminate this problem. Make sure the hole in the cap itself is clear from obstruction as well. The fuel tank has to "breath" as fuel is consumed.

You can find out which tank shrouds will fit your 8431 by going to Lawnboy.com and looking at the parts diagrams and part numbers and comparing them with other models that have a tank shroud. Many will interchange. It's even easier to do if you have a parts manual. There are some tank shrouds on e-bay right now that might fit. As far as the flat spots on the wheels, it might be better to replace them. Here is a link that might be useful: Lawn Boy

Well, I shortened the fuel line just slightly so it's running entirely downhill. Recleaned carburetor, this time with a WaterPick (the kind you use to clean your teeth that shoots little jets of water -- my new favorite carb cleaning method, because you don't have to fear spraying carb cleaner in your eye and can watch whether the water's come out well or not). Unbent a staple and recleaned the holes in the carb bolt. In the process of disassembling and reassembling, I discovered that one of the screws holding the air filter housing had a flat tip, while the other had a cone-shaped tip. It struck me as odd that the flat-ended one was in the hole that had gas and air passing through it, so I reversed them and put the cone-shaped one in the hole that had gas and air going through it. Somewhere along the line, I seem to have solved the problem, because I cut grass with the mower for about 20 minutes and it ran fine. So thanks for all the tips. Now my only concerns are: 1) my ear senses that the mower seems to be running a bit fast, and 2) the mower is definitely very loud compared to other mowers (muffler dosen't have any obvious external defects or holes). For what it's worth, the exhaust air seems to be blowing out of the muffler with tremendous force -- none of my other mowers make flowers, etc. flap in the breeze like this one does. Thoughts?

iowaboy ... I was cutting grass under moderate / light load. I've since re-tested the 10323 with stock jets ... 1999 10323 "E" Duraforce ... burned 12 oz of gas in 38.67 min - 0.31 oz/min ** Correction to previous 10323 test ... carb had a #67 drilled main jet & #78 drilled pilot jet. Note that this later test was done starting out with a drained fuel bowl AND tank before adding 12 oz of gas. I first added just a few oz. of gas to see how well it ran ... it ran good so I cut grass until it died. Then added my 12 oz. and ran the test on an already warmed up engine (figure warm-up time it another variable that should be eliminated for fair comparision). Realizing my first 10323 & 10424 tests may or may not have had gas in the carb fuel bowl, I re-tested the jetted 10424 just as I did the 10323. 2003 10424 "E" Duraforce ... burned 12 oz gas in 24.2 min. - 0.49 oz/min (#68 drilled main jet & "40" Suzuki Pilot Jet) This was a 19.5% increase of fuel useage ... empty vs. possibly full fuel bowl plus grass cutting load was more moderate even sometimes heavy this time. What is amazing is the comparison between these two latest tests ... stock 10323 @ 0.31 oz. / min. vs. jetted 10424 @ 0.49 oz. / min. ... a wopping 58% difference !! You also got to figure the 10323 has a drive load on it (including added higher speed 10550 gears) and the 10424 does not. The jetting on the 10424 is the absolute minimum (next larger drill size on main jet and "40" Suzuki jet is slightly smaller than the next larger #78 drill size). Also the 10323 has a lot more hours on it, but always ran perfect without even a hint of surging before jetting. The 10424 surged real bad when new and is only on it's 2nd mowing season ... rotated with my other mowers so you might say it is hardly even broken in. Next week I'll re-jet the 10323 so it is identical to the 10424 (1st test it was actually jetted one size richer on both main & pilot) to see how jetting really affects this mower. 7024 & 10301 had been run dry prior to my tests (7024 is retired and gets used only a few times a season / the 10301 still has the snail-speed gears in it so I don't really enjoy using it) so the only diffence in their tests and these new tests would be running time from a "cold start". Doug