Ok, first please bear in mind that I never worked on any small chainsaw engines before this month when I apparently successfully rebuilt my Stihl 191T which had a broken connecting rod (previously posted). That "knock-on-wood" success encouraged me to tackle my real prized possession ....... an 031AV that my 2nd ex-wife (have three of those) gave me for christmas back in 1980. It was my only saw for about 20 years, and then still gave me another 10 years of moderate use once I picked up smaller and bigger ones to help it out. It literally ran great for almost 30 years before it guickly started loosing power, running eratic, smoking excessively, and finally quit to nothing more than a gasping cough. I gave it up as shot and put it aside to eventually part out or sell complete on ebay.
I decided to have a go at it though and first bought a carb kit. I started it up after the carb rebuild and to my amazement it actually started running real good. But over the next 2 minutes as I tried to adjust the carb it quickly got worse, started smoking alot and wanted to quit. I could barely keep it running regardless of carb adjustment so I shut it down. I'm assuming that at this point the carb was good and I had other internal problems, probably worn piston, rings, cylinder, etc. and it was overheating and quitting. So I gathered up the modest tools I had and had at it. It took me the better part of the day to get it totally appart. It was easy up to the final step of separating the case to get the crank out. That sucker would just not come appart. I did not want to pry around the seam as to damage the gasket surfaces so I figured you just had to support one side of the case and drive out the crank to the other side. Easier said than done, that crank just did not want to separate from the bearings and let go. I was using blocks of wood to support the one side of the case with separation room underneath, pounding on the end of the crankshaft with a 20 oz hammer and block of hardwood. After pounding on this many times as hard as I dared the best I could do was just open up a crack in the seam around the case.
I was about to give up on it and just go ahead and part it out when my teenage daughter finally came down in the basement to see what all the noise was. She suggested I just get a bigger hammer! So I grabbed a 3 lb hand sledge and let it fly. Hard the 1st time, really hard the 2d & 3rd time, and presto, on the 4th slam it separated about a 1/4". I gave it one more big hit and she split in two.
My bottom line question is this. After I install a new piston/rings assembly and maybe a used/new cylinder, new bearings/seals, (crank actually seems really good) how do I go about adjusting the points. I can't figure how one would measure the gap with the flyweel out so you can get at them. I see the "hump" on the hub of the flywheel that opens the points, and they look pretty good, and the saw ran nice when first started up with the rebuilt carb, but I'd like to check it now.
I decided to have a go at it though and first bought a carb kit. I started it up after the carb rebuild and to my amazement it actually started running real good. But over the next 2 minutes as I tried to adjust the carb it quickly got worse, started smoking alot and wanted to quit. I could barely keep it running regardless of carb adjustment so I shut it down. I'm assuming that at this point the carb was good and I had other internal problems, probably worn piston, rings, cylinder, etc. and it was overheating and quitting. So I gathered up the modest tools I had and had at it. It took me the better part of the day to get it totally appart. It was easy up to the final step of separating the case to get the crank out. That sucker would just not come appart. I did not want to pry around the seam as to damage the gasket surfaces so I figured you just had to support one side of the case and drive out the crank to the other side. Easier said than done, that crank just did not want to separate from the bearings and let go. I was using blocks of wood to support the one side of the case with separation room underneath, pounding on the end of the crankshaft with a 20 oz hammer and block of hardwood. After pounding on this many times as hard as I dared the best I could do was just open up a crack in the seam around the case.
I was about to give up on it and just go ahead and part it out when my teenage daughter finally came down in the basement to see what all the noise was. She suggested I just get a bigger hammer! So I grabbed a 3 lb hand sledge and let it fly. Hard the 1st time, really hard the 2d & 3rd time, and presto, on the 4th slam it separated about a 1/4". I gave it one more big hit and she split in two.
My bottom line question is this. After I install a new piston/rings assembly and maybe a used/new cylinder, new bearings/seals, (crank actually seems really good) how do I go about adjusting the points. I can't figure how one would measure the gap with the flyweel out so you can get at them. I see the "hump" on the hub of the flywheel that opens the points, and they look pretty good, and the saw ran nice when first started up with the rebuilt carb, but I'd like to check it now.
) and I'm getting to like the extra growl she's got now anyways. 
