Hi to all on the forum.
SO, my engine is running but I cannot take it off of full choke, and when I give it some throttle, it stumbles and dies. To me this means a lean condition. All carb adjustments are default settings, so what is going on?
I unscrew the acorn nuts holding the intake manifold to the cylinder. One comes out easy, the other one is jammed so tight on the stud that it unscrews the stud out of the cylinder. Mind you, the manifold was already installed when I got the kit, so this 'workmanship' is from the factory.
The stud that remained in the cylinder has a hex hole in its end, the stud that came out also had a hex hole in its end, so I am thinking that there are hex holes on both ends of the studs. (I could not see the end that was jammed into the nut at this point).
I looked at the gasket that was between the manifold and cylinder and could see the seepage between the intake and the outside world. Clearly, this was indeed the problem.
I had to stick the stud in a vise to be able to get that nut off, but now the stud is a little messed up from the vise jaws. Now I see that there is no hex hole on this end of the stud, so it seems that the studs have the hex hole on one side only.
Luckily, I have a tap and die set, so I was able to nicely re-thread the stud, using an allen key in the hex hole to hold the stud so I could re-thread the entire length of the stud. I also ran the die down the other stud that remained in the cylinder (I tried to remove it, but it was tight, and I didn't want to risk snapping it). I replaced the stud into the engine with the hex hole facing out.
I was curious as to how far the studs go into the acorn nut's dome , so I milled off the dome and re-tapped the nuts.
The nut from the side that unscrewed easily and has the hex hole showing ended up stopping just a tiny bit below where the flat side inside of the dome would have been. The other side, where the stud was in backwards, and the nut was jammed onto it, the stud protruded out ABOVE where the flat of the dome would have been.
Clearly, when the engine was assembled:
1) one stud was installed backwards, and maybe not fully homed into the engine.
2) The inside of the acorn nut's dome was hitting the stud and jamming it, and was keeping it from bearing down on that side of the intake manifold flange to make a good seal against the cylinder.
I should have measured the protrusions of both studs, while in the cylinder, but forgot, maybe some other time.
Now, the engine is running good, I can take the choke off, and it seems to be OK.
I kinda feel bad
for a young person, who maybe gets an engine kit as a gift, or scrapes up the loot for one thru a job, or newspaper route or whatever, and maybe have to go through these kinds of problems with out a tap & die set, torch(I had to bend my crank to clear the pull-starter), vise, soldering iron, etc., and don't have anyone to turn to for help with the physical construction/modification/repair. Some people do not have the benefit of a garage and have to do these things outside when the weather is cooperating, and have no place to set up a workbench.
SO, my engine is running but I cannot take it off of full choke, and when I give it some throttle, it stumbles and dies. To me this means a lean condition. All carb adjustments are default settings, so what is going on?
I unscrew the acorn nuts holding the intake manifold to the cylinder. One comes out easy, the other one is jammed so tight on the stud that it unscrews the stud out of the cylinder. Mind you, the manifold was already installed when I got the kit, so this 'workmanship' is from the factory.
The stud that remained in the cylinder has a hex hole in its end, the stud that came out also had a hex hole in its end, so I am thinking that there are hex holes on both ends of the studs. (I could not see the end that was jammed into the nut at this point).
I looked at the gasket that was between the manifold and cylinder and could see the seepage between the intake and the outside world. Clearly, this was indeed the problem.
I had to stick the stud in a vise to be able to get that nut off, but now the stud is a little messed up from the vise jaws. Now I see that there is no hex hole on this end of the stud, so it seems that the studs have the hex hole on one side only.
Luckily, I have a tap and die set, so I was able to nicely re-thread the stud, using an allen key in the hex hole to hold the stud so I could re-thread the entire length of the stud. I also ran the die down the other stud that remained in the cylinder (I tried to remove it, but it was tight, and I didn't want to risk snapping it). I replaced the stud into the engine with the hex hole facing out.
I was curious as to how far the studs go into the acorn nut's dome , so I milled off the dome and re-tapped the nuts.
The nut from the side that unscrewed easily and has the hex hole showing ended up stopping just a tiny bit below where the flat side inside of the dome would have been. The other side, where the stud was in backwards, and the nut was jammed onto it, the stud protruded out ABOVE where the flat of the dome would have been.
Clearly, when the engine was assembled:
1) one stud was installed backwards, and maybe not fully homed into the engine.
2) The inside of the acorn nut's dome was hitting the stud and jamming it, and was keeping it from bearing down on that side of the intake manifold flange to make a good seal against the cylinder.
I should have measured the protrusions of both studs, while in the cylinder, but forgot, maybe some other time.
Now, the engine is running good, I can take the choke off, and it seems to be OK.
I kinda feel bad
for a young person, who maybe gets an engine kit as a gift, or scrapes up the loot for one thru a job, or newspaper route or whatever, and maybe have to go through these kinds of problems with out a tap & die set, torch(I had to bend my crank to clear the pull-starter), vise, soldering iron, etc., and don't have anyone to turn to for help with the physical construction/modification/repair. Some people do not have the benefit of a garage and have to do these things outside when the weather is cooperating, and have no place to set up a workbench.