K7SGJ
09-04-2014, 06:26 PM
My small tractor has been acting strange over the last few months. When running around, the engine would act like it was going to quit, then go back to full performance. Two days ago, I changed a belt for the hydrostatic drive, and when I finished, I ran it out to one of the back cargo containers to check on a bee problem we've been having. Seems the little buggers built a hive under one of them, and they were swarming everywhere. My treatment worked okay. (I tried to scare them by yelling BOO BEE, but I had to take a more drastic approach) But I digress.
So I jump back on the tractor, flip the ignition switch, and push the starter button. Crank, crank, crank, but no start. I open the engine compartment to see if there was anything obvious, but no. I try the start sequence again, and after several tries, it sparks up, and runs fine. I get it back to the house, shut it down, and try a restart. Lots of cranking, but no start. Now there is fuel leaking out of the carb. Must be a fuel problem right? Just to be sure there is spark, I pull the spark plug lead and put it across my spark tester, and give a few cranks. There is spark, but to me, it looks a little weak, but it is there. I pull the carb and look at the float, needle valve, all of that. Everything is in spec. Fuckit. I put it all back together and figure I'll look at it later.
Today, I try to start it, and all it does is crank. Just for the hell of it, I decide to look at the points. I pull the cover off and check. Yep, .020 gap. Perfect. I try my spark tester again, and this time, no spark. Hmmmmm. So just to make sure the points are closing all the way, I put an ohm meter across them. I rotate the crankshaft manually, and when the points close, continuity. Damn. Then, one of my clip leads pop off the points, so I put it back to try a few additional revolutions. The first time around, continuity, the second time, nada. WTF?
So, I rotate the crankshaft till the points are closed again, and nothing. Thinking I might have an intermittent connection from the clip lead to the part of the points where the cap is connected, I move it slightly. The tone on the continuity meter starts chirping. This is interesting. So I wiggle that part of the points and continuity comes and goes with the points physically closed. So I pull the points for a closer look. I put it under the magnifier, and notice that where one side of the points were swaged to the point frame was wobbly. I could actually rotate the contact on the frame. Sumbitch. This would explain the intermittent loss of power, and all the other issues.
I look in my box of engine spare parts, and no points. But I did find a solid-state device that would replace conventional points. I had two of them, and have no idea when or where I picked them up. Maybe a garage sale. Anyway, it's worth a try. I bypass the points and temporarily put this little wiz-bang in. Try the spark tester, and a nice big blue spark appears. I put the plug back in, hit the starter, and bang, a big backfire through the carb with associated flame appears. I didn't need the hair on that eye brow, anyway. I brought the halon bottle a little closer to where I was working, and tried it again. This time, the engine took off like Hogan's goat. (who the hell is/was Hogan, anyway?)
So it was just a matter of putting the old points back in to hold the point contactor and rubber seal in place so engine oil wouldn't shoot out, and make a mount on the block for the little wiz-bang for good electrical contact as well as a heat sink of sorts. Put it all back together, cleaned up the mess, and took it for a spin. It works great. It takes off on the first crank every time. Oh, the fuel leaking from the carb? It appears it was just a matter of the bowl being full, and the vibration from the engine cranking caused it to escape through the throttle valve shaft which is a bit worn. But, when the engine is running okay, no fuel leaks since the fuel is flowing and the bowl isn't fully filled. I'll address that next time I have to pull the carb off.
Now I have to do an annual on the big tractor and the forklift. But I'm going to wait till it cools down a bit.
So I jump back on the tractor, flip the ignition switch, and push the starter button. Crank, crank, crank, but no start. I open the engine compartment to see if there was anything obvious, but no. I try the start sequence again, and after several tries, it sparks up, and runs fine. I get it back to the house, shut it down, and try a restart. Lots of cranking, but no start. Now there is fuel leaking out of the carb. Must be a fuel problem right? Just to be sure there is spark, I pull the spark plug lead and put it across my spark tester, and give a few cranks. There is spark, but to me, it looks a little weak, but it is there. I pull the carb and look at the float, needle valve, all of that. Everything is in spec. Fuckit. I put it all back together and figure I'll look at it later.
Today, I try to start it, and all it does is crank. Just for the hell of it, I decide to look at the points. I pull the cover off and check. Yep, .020 gap. Perfect. I try my spark tester again, and this time, no spark. Hmmmmm. So just to make sure the points are closing all the way, I put an ohm meter across them. I rotate the crankshaft manually, and when the points close, continuity. Damn. Then, one of my clip leads pop off the points, so I put it back to try a few additional revolutions. The first time around, continuity, the second time, nada. WTF?
So, I rotate the crankshaft till the points are closed again, and nothing. Thinking I might have an intermittent connection from the clip lead to the part of the points where the cap is connected, I move it slightly. The tone on the continuity meter starts chirping. This is interesting. So I wiggle that part of the points and continuity comes and goes with the points physically closed. So I pull the points for a closer look. I put it under the magnifier, and notice that where one side of the points were swaged to the point frame was wobbly. I could actually rotate the contact on the frame. Sumbitch. This would explain the intermittent loss of power, and all the other issues.
I look in my box of engine spare parts, and no points. But I did find a solid-state device that would replace conventional points. I had two of them, and have no idea when or where I picked them up. Maybe a garage sale. Anyway, it's worth a try. I bypass the points and temporarily put this little wiz-bang in. Try the spark tester, and a nice big blue spark appears. I put the plug back in, hit the starter, and bang, a big backfire through the carb with associated flame appears. I didn't need the hair on that eye brow, anyway. I brought the halon bottle a little closer to where I was working, and tried it again. This time, the engine took off like Hogan's goat. (who the hell is/was Hogan, anyway?)
So it was just a matter of putting the old points back in to hold the point contactor and rubber seal in place so engine oil wouldn't shoot out, and make a mount on the block for the little wiz-bang for good electrical contact as well as a heat sink of sorts. Put it all back together, cleaned up the mess, and took it for a spin. It works great. It takes off on the first crank every time. Oh, the fuel leaking from the carb? It appears it was just a matter of the bowl being full, and the vibration from the engine cranking caused it to escape through the throttle valve shaft which is a bit worn. But, when the engine is running okay, no fuel leaks since the fuel is flowing and the bowl isn't fully filled. I'll address that next time I have to pull the carb off.
Now I have to do an annual on the big tractor and the forklift. But I'm going to wait till it cools down a bit.