High Idle

WATCHMAKER

Member
Joined
Mar 23, 2005
Messages
116
Location
Northern, WI
I have been working on getting my 780 jetting dialed in and I now have a high idle that comes back down to normal after 10-20 seconds. My first thought was my pilots are too lean. I had 47.5's in and now 45's. The 47.5's sounded a little fat and the 45's sound crisp and accelerate great. Could a momentary high idle be caused by a slightly too lean mid range? I am wondering if I should richen the pilots or mid range. Plugs look good at all speeds. Here's my jetting.........156.3, 155, 155, needles raised 1/2, 45"s @ 1-1/2 turns.
Thanks

:rocks:
 

I Would Say Keep Turning Out The Air/fuel Screws Until It Goes Away , If You Go More Than 2 1/2 Turns Out Your Going To Need To But Those 47.5 Back In ...just My .02

Also A Quick Fix Is Lower Your Idle Rpms To 1400 Rpms..
 
B2SO said:
Also A Quick Fix Is Lower Your Idle Rpms To 1400 Rpms..
My idle does return to normal after 10-20 seconds.



How much overlap is there between pilot sizes? For example is a 45 @ 2-1/2 turns about the same as a 47.5 @ 1 or 1-1/2 turns?
 
open your fuel screws 1/4 turn and it will go away, just make sure they aren't open more than 2.75 turns, or you gotta go up to the next size pilot and close the screws some
 


Back
Top