Made back in the old days, I'm guessing 70's and sold by Western Auto. Well, I'm trying to find out what spark plug it takes and had some spark plug questions as well. This one is real hard... sorry for the length. I found out in the owner's manual it takes a Western Auto stock number something plug. (Manual not handy right now.) Guess what. Nothing crosses to it now. I did look up the Briggs and Stratton engine model number (5 HP) and found on B&S website a part number for the plug. The magic number is... 298809, which apparently is so old it has been replaced by 802592S. Apparently the 802592S B&S plug is in a league of its own because I can't find anyone, Champion, NGK, Bosch, etc. that will cross it. I've seen some sites say a Champion RCJ8 and some say a Champion RJ19LM. Two different plugs... Leads me to my quest for help. This is a tiller (old) so if I get a R plug, does it matter? R = Resistor. From what I've read about resistor plugs it cancels the radio frequency build up that may cause issue with electronics (in autos mainly, etc.), but this is an old tiller, might not need an R, but will an R cause issues? Now, after saying all that, I would like to get either a RCJ8 or a RJ19LM because I have other stuff that uses those plugs and those manuals say to use them. Since my tiller manual is so old, and references a Western Auto part number that likely does not exist anymore, would it matter if I used a resistor plug or not in a little old tiller? After all that. The plug in it right now is an Autolite 255. Of coarse, non resistor, but I don't know if it's been in there all these years or not... I acquired the tiller from an uncle that worked on small engines most his life, so who knows what the original spark plug was? Probably the Western Auto part number, hee hee. So, to sum up. Would a resistor plug matter in an old tiller? I would like to get one as I have other equipment that take the RCJ8 or RJ19LM so I can limit my plug purchases to just 2 or 3 different types, but if it will screw it up I can expand my plug inventory if necessary. I don't have anything against Autolite, but it's the only oddball in my "fleet" of small engine equipment. Also, do you think those plugs are the equivilant of the B&S 802592S or what's the best guess on a cross? I'm just wanting to replace it with the right thing and I don't want to burn up something that has been running great for so many years by putting a plug that's not right for it. Since it has been in the family so to speak for all this time, it's kind of sentimental you know... 'Coarse it could blow up tomorrow anyway... Sorry to ramble, but another question I have is does anyone know the difference between the Champion RC12YC (leaf vac) and the Champion QC12YC (chipper/shredder)? Something about EMI. I'm thinking Electromagnetic Inteferance... Can I just buy one plug or the other for these? I don't have the manual for the chipper/shredder, but the leaf vac is about two years old and definitely came with the Champion RC12YC. When I buy them, would like to just buy the RC12YC unless you think I need to stick with a QC12YC in the MTD chipper/shredder, both B&S by the way. Thanks in advance for any help on probably such an easy topic. I just don't know much about plugs and it seems everything I have currently has something different in it. I'm planning on doing some PM and am wanting to take advantage of buying as few types of plugs as I can. Hope that makes sense.