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Old 09-27-2010 | 10:36 PM
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jpalessi
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Originally Posted by JoeC
I have a new limited edition os vspec that I have about 2 qrts on now and I am fighting a high rev before it idles down. The top end runs great but when you let off the throttle it takes about 7-10 seconds before it will idle down. I have tried everything to adjust it and nothing will work. Someone told me the carb could be defective but I wanted to get some input before I have to buy a new carb. The fuel tank is new, clutch and bearings are new, air filter was clean, and fuel lines are new. I also made sure the linkage was adjusted properly as well.
Originally Posted by JoeC
The linkage is bind free and the idle gap is good. I took the motor apart and sealed it with lucky7 prior to breaking it in.
First i want to thank you for using Lucky 7 products. second i want to tell you that if you read the instructions L7 engine sealant is intended for external use only, no dis-assembly is required. Lucky 7 sealant is a coating, not a gasket.

now for your tuning. getting the perfect mixture between the LSN, MRN, and idle will eliminate any 2 stage idle on any engine. first set your idle to 1-1/4 turns in from closed, and know you dont need to touch it more then 1/8 to achieve the perfect tune. then start leaning the lsn 1 hour at a time and you should notice the 2 stage idle becoming shorter and shorter as you lean the lsn. the 2 stage idle is simply the engine loading up and burning the excess fuel in the case, now with that said if you lean the lsn too much the idle will go high and stay high, turn it back out 1 hour till its stable. < now you're close. from here make fine tuning adjustment between the LSN, MRN and idle. understanding how the needles effect each other will help you make the right adjustments so i'll give you a quick breakdown. the LSN and MRN work with each other adjusting the fuel consumption from idle to the mid rpm range, these needles should be adjusted together to achieve the optimum tune. for example if you lean the lsn 1 hour you should richen the mrn 1 hour, and vis-versa. this adjusts the fuel up or down the rpm range w/o changing the overall mixture & consumption, which will effect your idle, as well as low - mid range power. much like adjusting your idle for compensation when playing with LSN these needles effect each other. I hope this helps you have a better understanding of your idling issue.

These engines are extremely easy to tune and soo many ppl don't ever get the lsn, mrn, idle right. they easily tune the top in, lean the bottom a little and call it a day. I'll tell you what tho, if you spend the time and get the bottom dialed in you'll see the full potential of your engine and i bet you're amazed with how awesome they really are. <this goes for any brand or model.
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