84 G1 running issues

[super99]

My G1 will run great and then the next time you get on it, it won't run very good at low speeds. I took it to a 3 day tractor show a couple of weeks ago, Friday it ran great, Saturday am also, then later in the day, it would barely keep running. I replaced the new spark plug and it didn't help. I used it today, it ran great, I was hauling some tools and lost a couple, and I drove real slow looking for them. Later I was going to ask the wife to ride down to the cornfield to pick an ear to test and it was running so bad I was afraid to drive it out of the yard. It has had the fuel pump replaced with a electric pump before I got it. I put a new fuel pump on it this spring. I read the thread about fixing the throttle shaft bushing, mine was wore bad, so I replaced the bushing and then soldered the throttle shaft to get a better fit. It ran great after that. I barbecued the muffler to clean it out. I put a new spark plug in it. Sometimes it runs great and the next time it runs like it did before the carb repair. I have read about replacing the crank seal, BUT, if the seal was bad, wouldn't it run poor all of the time? On the lower back side of the engine, there are 2 short nipples coming out of the block, one has a hose attached and the other one doesn't( maybe went to the fuel pump?). I cut a short hose and plugged the end and put it on the open nipple, but it keeps blowing off. Any ideas or suggestions appreciated. Thanks, Chris

[Field6565]

If your crank seals are bad then you should see some kind off oil/seepage behind the clutch or under the cooling fan. That nipple on the lower part of the block was a pulse to run the original fuel pump. If it is not being used it should be closed off. It's sucking air. Two strokes hate air leaks. Maybe try putting a hose clamp on it.