Originally Posted by terrible-t
Here' my 2 cents. Bubbles in fuel line, 2X longer on pressure line compared to tank to carb. Seal line from carb to tank w/ATV sealant. Metal noise in idle only! right!. Adjust LSN to the richer side. The metal sound you hear is like pre-ignition on the engine, or running to lean. When you have the engine running, adjust the idle speed first. Then HSN till you have good accel to idle. Then you adjust the LSN. Turn LSN cw(leaning) till the idle start to rise, and stop. Turn the LSN CCW till the idle spped drops, and add a 1/4 turn CCW. That will let you idle on the rich side. The sound should be gone.
See what happens with that procedure. Let me know.
The hobby shop guy found the tank leaking and re-place a new one. that explain why my all needle had to be so lean and the more i tune the more i'm getting nowhere. with the new tank i can run HSN at 1 3/4 open from close & still a tag too rich but it runs fine as it suppose to be for breakin in.
As for LSN, i got it correct using the 'Pinch' test so that one is done.
As for the brownish stain, strangely it gone now. The guy say it's castor oil buildup and should be fine.
Now, i face a another problem ... when startup from cold, it will not fire up with the carb opening at 0.5mm. I have to switch off the receiver and pull the throttle link to at least 50% opening then it will fire up then immed i switch on the receiver to let it goes/jump back to 0.5mm opening. subsequent start up after that is fine. What is the cause here? the fuel don't get in enough when the crab is open 0.5mm?
As for the constant metal buzz, the guy says it comes from the exhuast and it's common. is it true?