JD 40 Fuel Additive

As far as additives, what has worked for me and I run now is, I add a small can of the low ash 2 cycle motor oil (maybe Mercury Quicksilver) to the gas when I fill the tank, I run Marvel top oil in the crankcase (NOT gas, it fouled my plugs), and I pretty much use Sta Bil gasoline stablizer year round since the tractor sits a lot. Of course, just regular 87 octane gas.

Good topic and it will be interesting to hear several opiions on what others use for additives.

Best wishes n God Bless

John T

~Those Dubuque tractors tend to fowl spark plugs to begin with & a lead substitute will make it even worse..

~I doubt you will find a real additive anyhow as most areas have banned actual lead additives.. [most additives are actually just lead substitutes now]

~Here is my personal take on using a lead additive: IF the tractor isn't worked hard enough to turn the muffler & exhaust pipe red then an additive isn't needed.. If a tractor is worked hard enough to turn the exhaust red then there is a chance of valve to seat recession if hardened seats or an additive isn't used..

~If you want to add something for light duty use & to help lube the upper end a little just add a few ounces of 2-cycle oil to each tank of gasoline.. 2-cycle oil will add a little valve lube, will help the rings seal a little better at start-up & low RPM’s, & it burns much cleaner & better than Marvel Mystery Oil..

JDClooney@aol.com

Howdy...you stated, "Those Dubuque tractors tend to [foul] spark plugs to begin with & a lead substitute will make it even worse.."

Is this a function of design, plug selection, fuel selection/mixture, operator usage/error or combinations?

I hope you would concur that if Champ. H10C's [gapped correctly and clean], new fuel and heavy loads/usage were applied, this would probably prevent fouling. If not, then what can a M/40/etc, series owner do to prevent unwarranted plug fouling? I believe, and know you would concur, I have no control over design.

thanks,
tom

~In a lot of cases it's lower compression due to wear.. Then the newer emission gasoline that's made for higher compression engines takes more of a spark to get it to ignite [probably the big reason].. Then the spark plugs of late don't seem to have much of any glazing on the center porcelains & that promotes fuel fouling.. The M-430 also have a rather weak ignition system & that allows the spark to bleed off before it builds high enough to jump the plug gap.. Some of the replacement condensers seem to be mismatched & that lowers the spark output a little.. The updraft carb has a tendency to plug up the air inlet bronze fuel drain.. The ignition switches tend to increase internal resistance with age & that lowers the spark.. There's more but you get the idea....

JDClooney@aol.com