2013-04-12 Hi - I got this tiller new around 2000. The label on the side says: MTD Yard Machine, 5.5 HP, Chain Drive 13, 22,24" Tilling Machine, DO2673 AC The label below on the frame says: Model: 21A-342-062 Manual says: Front Tine Tiller Models 340-390 Engine: 5.5 hp Briggs and Stratton Engine Model Series 133200, 134200, 135200, 136200, 137200 Well it sat outside all winter this year and it just would not even sputter. So pull the plug... Problem: No spark So I romve the flywheel cover and and find flywheel and coil are rusty as heck. I clean both till shiny and space with 1 layer of paper. Got spark! Problem: Runs like crap. Not getting gas. This started a few years ago and this season it got to the point that it would not run. I had been getting by by setting choke part way on but it got to the point that it was full on and still seemed to be starving for gas. I figured it was a carborator diaphram or gasket as the engine is one of these newer types where it has to suck the gas up from the tank below. I started by taking the side cover off of the fuel pump and looking at the diapham. It had no tears and seemed to be sealing all the way around all perimeters. I left the diaphram, spring, and cover off and continued to remove the carborator and tank by doing this: - Remove gas from tank. - Remove the controls from the tank- 2 star screws and OBSERVE and disconnect linkage. - Unbolt carb from block - 2 star bolts, bottom one is tough, got it with a star bit and a tiny wrench to turn it. Found 10mm wrench kinda fits too. - Unbolt tank from block at bottom - 1 bolt - Tip whole thing away from block and OBSERVE how linkage and springs are connected to governor as you disconnect them. This will require that you temporarily remove the small long bolt holding the plastic cam that holds one of the linkage bars. Reconnect bolt when linkage is free. - Remove carb from tank - 3 star screws - one long one goes right through carb. - Inspect pickup tubes. On mine the big one was very clogged. I thought it was the problem. I found that I could spray carb cleaner into the top hole of the fuel pump and it would blast out the pickup screen. - Inspect brass the idle jet. This is on the opposite side from the fuel pump. The one I have has a slotted head. The carb end has a larger hoe in the end and a smaller hole drilled from side to side, so they form like a T. I guess gas sprays out the sides. I took a twist-tie and stripped off the plastic and used that thin wire (and cleaner) to probe holes to make sure they were clear. I saw some online parts diagrams that showed another type of adjustable needle valve and spring deal. Don't know it that's an upgrade or what. - Spray out that hole int the carb and all the others and be sure they are clear. - Make sure stuff stays clean and put everything back together. Ok after doing that I had the same condition , starving for gas. Poop I went and got a diaphram (Briggs part# 272538S $3) and put that in and got same. Poop poop... Well I quit for that night and mentioned it to George H who I saw later in the evening. He said clean out the exhaust port. He used to have that all the time with his weed wackers etc. I thought , "yeah right... " The next afternoon I was going to take it all off and be double sure all holes were clear. But before I started that I took off the exhaust and looked in. It did not seem clogged at all, a little dry soot was all. I thought for a minute and decided just to be sure I would take the head off. There I found a crusty layer of carbon on the side where the gas enters. It didn't seem that thick really but I scraped it off with a sharp painting tool and then used some 100 grit drywall sandpaper to shine it all up pretty well. I reassembled and cranked it up and it ran like a top!!!! I tilled for a couple of hours and it kept running great... So there you go, you just never know! Alright George!!! And I have a cleaned up carborator to boot! I'll be good for another 10 years? (right) I must say that I found a good parts reference here: http://www.ereplacementparts.com/briggs-stratton-133200-series-engine-parts-c-16758_17347_22210.html?page=2