B-212 misadaventure and a few questions

August 24, 2008

Several months ago I found and bought a B-212 that had been parked under a tree left for several years. I posted pictures here: http://www.simpletractors.com/club2/topic.asp?TOPIC_ID=95240 Well, a few weeks ago I brought it around to the garage just to put some tires that were round on it so it would be easier to move around, and the wife suggested we put it in the tractor shop position so I could work on it as time permitted. I haven't spent much time with it until this weekend, other than spraying some rust penetrant on the bolts every time i walk by. I finally had some time to tinker this weekend, so I decide to remove the engine and see if it could be coaxed into running. The idea was to get a running engine then see if the BGB and variable were in OK shape before complete disassembly. The rust was such that at every turn another simple job would turn complex. First, one of the U-nuts that hold the grille shell on, broke off and I had to grind the head off to remove it. Once the grille shell was off i found there was mud and dirt caked up to the frame level. Shop-vac was removing good for removing that, but really angered the wasp nest under the shroud. Glad I had insecticide close by! Drive shaft bolts came out easy, but engine mount bolts didn't. Had to find a way to wring one of the bolts off. Got engine up on the bench, seems to have spark when i hand turn the flywheel, but no compression. Felt air coming out breather, wonder what that means, so I pull the head and realize that when it was parked, the exhaust valve was up and rusted into that position. More penetrant, gentle taps, no solution. OK so then decide to use a 10HP I have and move the coil from this engine to it so it won't need battery ignition. Put it up on the bench, take off the incorrect magnetron coil that someone had put on before I got it. Interestingly, this coil had been installed wrong, and the stop wire were rubbing the flywheel, which probably explained it's previous random behaviour. SO, I take this coil out, put in the one from the 12 HP, and even though it will shock me, it won't fire the plug. A variety of misadventures with trying to rig the S/G to turn over the motour follow. Final result is using the car battery to turn over the motour, and end up replacing the coil with a new one I had bought at an old hardware store last month. With this the engine began to run. Then I realize that without 4 spacers, this engine won't fit, since the 12HP has an integral hydro lift pulley. Try to find solution to this, none is apparent until I found two more drive-shaft spacers. Thinking I've won, I bolt in the engine, and try to hook up the drive-shaft, but find that one spacer is too little and two is about 1/8" too long. At this point Supper is ready, so I give up and go in, hoping to have time to buy 3/8" worth of washers tomorrow. Not sure there is any point to this post, but it was somewhat of a relief to share the story. Despite the frustrations it was still fun. Questions: Could the booster fan and special pulley from a 12HP have been used on the 10HP without a problem? Is there a good way to Fix the stuck exhaust valve easily? I have a Kohler engine I could try, but does any one know how the mounting bolt to drive adapter spacing compares to the Briggs? Any idea why a coil would be able to shock me when I hold the plug wire and move the flywheel by hand, but not fire a plug when I spin with the S/G?

August 24, 2008

quote:
Originally posted by GWGAllisfan Any idea why a coil would be able to shock me when I hold the plug wire and move the flywheel by hand, but not fire a plug when I spin with the S/G?

Yes. This is symptomatic of high resistance in the secondary high voltage winding. For example, if there is a break in the wire or within the coil then when it creates spark most of the energy in the spark is lost jumping that gap. Your nervous system is a far better detector of electricity than the plug. So less voltage and less current will still give you a bite but lack the power to produce a hot spark. This is why the experts keep telling us to get a real spark tester vs testing with a plug held against the plug or using your fingers. I don't suggest you try the hand thing with a fully functional magneto (because the current probably flows through the heart in going hand to hand) but if you did you'd probably feel the extra kick. So, in summary, yeah, you needed a new coil. good luck with the rest. I'm thinking you drained the oil and replaced it. Was there water or rust in the old stuff? (hope not!) -Don

August 24, 2008

I would try to remove the valve and clean up the stem, then put some oil on it, get it to move smoothly before putting the keepers on again, as for booster fan pulleys, they should interchange, all of the newer 10 hp briggs used in the 3400 series and 7000 series had the aluminum pulley, be sure to loosen the allen screw on the driveshaft flange at the BGB, this will allow the driveshaft to slide to fit whatever spacers you use with the engine to driveshaft bolts, without putting stress on the flex discs.

August 25, 2008

Is there a way to loosen the allen on the BGB without complete dissasembly of the dash? I've pretty much given up on the 12HP for now, until I can find a way to fix the valve. The 10 HP should be good enough to make sure the BGB and Transaxle are OK, before i go into a repaint.

August 25, 2008

Yes there is a hole in the frame underneath, just have to turn the shaft till the set screw is down.

August 25, 2008

For the exhaust valve, squirt the stem with PB Blaster one day and some fuel oil the next. A tap per day with a brass, plastic or hide mallet. But I would first remove the breather to pull a loop of emery cloth back and forth to remove any rust build up on the stem. If you get the stem down it might not want to come back up. I would try to get the valve out to clean up the stem, then reassemble the keeper(s). Check/remove the intake also just in case.

August 29, 2008

I got it to almost run. Wednesday night i went the rubber hammer and spray penetrant route. Forced it down, a little them made sure the cam would raise it, then repeat. Before long it was going up and down like it should. Cleaned the underside of the valve and valve seat, and now I have compression. Tinkered with the spark, none with magneto, tried rigging a battery coil and found points were not conducting, so new points, and some wire... we have spark!. Bolted a hopelessly bad carb on, just to give some intake restriction, then with some fuel poured in the carb body, and a shot of starter fluid, it eventually fired and ran for a few seconds, once or twice.....However by this point I had pulled the rope enough to wear a blister on my finger. SO...Weekend plan is to hook up a S/G, rebuild the carb and see if I can get some sustained running time. This B-212 just became part of my daughter's FFA project, so I will have some help, but a deadline comes with that. I'm sure we will be asking a lot of questions about the variable speed unit as I'v never messed with one of those.