Timbone
Well-Known Member
You can see my project under the thread “New project idea”. I have pretty much finished the motorcycle/ motorbike. I should be doing my first rounds of road testing by now. But my engine won’t kick! I’m gonna need a really good idea.
The engine is a 140cc Briggs that I converted to horizontal use. I’m using the stock carb that I converted to run at 90*. I built a custom throttle body that converted 100% butterfly valve movement to equal full throttle input turn. No problems there. I have the fuel tank on and I have good fuel line.
Spark is powerful. Compression is good.
After my first set of tries (including starting fluid), I got nothing. No pop. No smoke. Engine feels right when I pull the starter cord. I’m using choke. Not using choke. Trying every throttle position. Nada.
I removed the valve cover. The rocker arm had unseated from the push rod on the exhaust valve! That’s gotta be it! I reseated everything, replaced the cover, tried again. Nothing.
So I removed the spark plug (checked for spark) and removed the valve cover. This engine is pristine! Slowly I spun the crank by hand, starting at TDC and working thru all four strokes. Just after TDC, exhaust valve opens then closes - back to TDC and slightly beyond when the intake valve opens and closes - both closed for TDC. Sure seems perfect.
I’m just using a tiny bit of gas - from my premix stock. I figure it should pop regardless, a little 2 stroke oil won’t matter much. There’s plenty of gas in the float bowl and I have blasted starter fluid into the carb throat.
Am I missing something?
Thanks in advance!
The engine is a 140cc Briggs that I converted to horizontal use. I’m using the stock carb that I converted to run at 90*. I built a custom throttle body that converted 100% butterfly valve movement to equal full throttle input turn. No problems there. I have the fuel tank on and I have good fuel line.
Spark is powerful. Compression is good.
After my first set of tries (including starting fluid), I got nothing. No pop. No smoke. Engine feels right when I pull the starter cord. I’m using choke. Not using choke. Trying every throttle position. Nada.
I removed the valve cover. The rocker arm had unseated from the push rod on the exhaust valve! That’s gotta be it! I reseated everything, replaced the cover, tried again. Nothing.
So I removed the spark plug (checked for spark) and removed the valve cover. This engine is pristine! Slowly I spun the crank by hand, starting at TDC and working thru all four strokes. Just after TDC, exhaust valve opens then closes - back to TDC and slightly beyond when the intake valve opens and closes - both closed for TDC. Sure seems perfect.
I’m just using a tiny bit of gas - from my premix stock. I figure it should pop regardless, a little 2 stroke oil won’t matter much. There’s plenty of gas in the float bowl and I have blasted starter fluid into the carb throat.
Am I missing something?
Thanks in advance!