Trip
Well-Known Member
Last summer in a quest for more power, I decided to add the (brand new) 28.5cc kit I had laying around. The top end kit went together well and fired on the first pull.
It never ran quite right. It refused to idle and bogged like crazy on the low end. After some needle tweaks I got it to run half-assed. It sounded like I had an air leak, so I grabbed my can of starting fluid and checked for leaks. I didn't find anything, so we packed up 4 FG's and headed to "The Pit" The truck ran somewhat ok but didn't have the power it did before I put the big bore kit on it. It ran for about 5 minutes then begain to get really weak, I mean it wouldn't even spin the tires in loose dirt. Then all of a sudden it stalled, it was hard to pull over, so I just brought it home and let it sit.
Today I finially decided to see what was going on, so I tore it apart. Looks like a wrist pin clip decided to come loose and break-dance all over inside. What a mess. So I cleaned everything out (I did not seperate the crank case) I used about a quart of 2 stroke gas and flushed and flushed. After I was sure everything was clean and the big-end rod bearings looked clean and in good condition. I threw the stock 26cc head (and piston of course) back on and sealed everything up (and I mean everything) with Permatex Ultra Copper. The only thing I could find in the crank case was a small piece of wire (in the pic below) I find it strange though, this wire is perfectly straight. hmmm?
Back in the truck I set the h needle at 1.5 and the low at 1.25 and it would not start, so I richened both up 1/4 turn. It fired up, but has the same lean bog it did last summer. I can make little or big carb adjustments but it makes no difference, still sounds lean.
It will not idle for more than about 2-3 seconds before it starts to die, a couple full throttle burps and it runs better for about 2-3 seconds, the the problem repeats itself. I should note the arrow on the piston is facing the exhaust port and the ring gap is facing the intake. Also I have a Jet-Pro silenced version 1.
Fuel flow form the fuel lines appears to be fine as it dumped half a tank all over my work bench. I connected the yellow fuel line to the top and the black line to the bottom of the carb. Is this correct? The motor and carb are stock other than the J/P pipe.
Any ideas?
Thanks Guys,
Trip..
**EDIT**I finally have a better camera, so here is what the piston and head looks like..
It never ran quite right. It refused to idle and bogged like crazy on the low end. After some needle tweaks I got it to run half-assed. It sounded like I had an air leak, so I grabbed my can of starting fluid and checked for leaks. I didn't find anything, so we packed up 4 FG's and headed to "The Pit" The truck ran somewhat ok but didn't have the power it did before I put the big bore kit on it. It ran for about 5 minutes then begain to get really weak, I mean it wouldn't even spin the tires in loose dirt. Then all of a sudden it stalled, it was hard to pull over, so I just brought it home and let it sit.
Today I finially decided to see what was going on, so I tore it apart. Looks like a wrist pin clip decided to come loose and break-dance all over inside. What a mess. So I cleaned everything out (I did not seperate the crank case) I used about a quart of 2 stroke gas and flushed and flushed. After I was sure everything was clean and the big-end rod bearings looked clean and in good condition. I threw the stock 26cc head (and piston of course) back on and sealed everything up (and I mean everything) with Permatex Ultra Copper. The only thing I could find in the crank case was a small piece of wire (in the pic below) I find it strange though, this wire is perfectly straight. hmmm?
Back in the truck I set the h needle at 1.5 and the low at 1.25 and it would not start, so I richened both up 1/4 turn. It fired up, but has the same lean bog it did last summer. I can make little or big carb adjustments but it makes no difference, still sounds lean.
It will not idle for more than about 2-3 seconds before it starts to die, a couple full throttle burps and it runs better for about 2-3 seconds, the the problem repeats itself. I should note the arrow on the piston is facing the exhaust port and the ring gap is facing the intake. Also I have a Jet-Pro silenced version 1.
Fuel flow form the fuel lines appears to be fine as it dumped half a tank all over my work bench. I connected the yellow fuel line to the top and the black line to the bottom of the carb. Is this correct? The motor and carb are stock other than the J/P pipe.
Any ideas?
Thanks Guys,
Trip..
**EDIT**I finally have a better camera, so here is what the piston and head looks like..
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