vnmsgt

iTrader: (2)

I have a Picco P-3 that I cannot get the rpms to come down off of jumps. It is real bad. I have about 20 tanks on it and only leaned out the top end about a half turn from out of the box. It ran great till about the 10th tank and then did this. I sealed the whole engine (backplate, carb and where carb goes into the case). Also tried another carb and still did it. I had this problem before on another motor and the LSN was too lean. I leaned out the LSN 2.5 turns from where it was out of the box (never touched it before this time) and it still did it. NO change at all. I went to check with the manual to see where the needles are supposed to be and found my HSN to be 4 turns out when the manual said 3-3.5 turns and the LSN was only 6 turns out when the manual said 10.5-11.5 turns out!!! And I was 6 turns out included the 2.5 I just did. The LSN is sticking out of the slide about 1/8 inch. Is that normal. I have not run it this way yet as I took the motor out I was so frustrated with it. Where do you guys run your LSN's at on this motor? Is it probable that the needles, especially the LSN to be over 6 turns too lean out of the box???? Never saw that before.

Taylorm

Ever change the O-rings on your HS and LS needle? Change them all and go back to factory settings and see what happens.........put in a new plug for good measure..............air leaks suck......you will chase your tune till your head explodes.............

Roelof

Problem can also be caused by the exhaust or the tank

Maximo

iTrader: (11)

i'll bet the carb body is leaking !!!! where the metal end bell is pressed into the composite main body....this is the same area that can leak on the Go engines...a seam of JB weld will cure that !!!

fuel filters... notorious for leaking... remove any external fuel filters...

nitrodude

iTrader: (8)

First of all, you cant go by the manual, it all depends on where you run the car. Altitude, humidity, air density, and weather all play a role on how you tune the engine. Second, I would say that Piccos tend to loosen up at about 15-20 tanks, and when they loosen up you need to retune. Third, idle that takes too long to come down means that your LSN is too lean, so yeah, go rich, and see how the engine runs. The idle needs to come down pretty quick after you rev it all the way up. Just richen the LSN and tune from there.