Idle mixture screw question. |
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Idle mixture screw question. |
Cevan |
May 10 2010, 08:38 PM
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#1
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Senior Member Group: Members Posts: 1,079 Joined: 11-December 06 From: Western Massachusetts Member No.: 7,351 |
So I've got the engine running and now I need to adjust the carbs (Weber IDFs). The Weber website says to start with the idle misture screws 1 turn out from lightly seated. But mine seem to screw in until the spring is completely compressed. Does this sound right?
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jmill |
May 10 2010, 08:52 PM
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#2
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Green Hornet Group: Members Posts: 2,449 Joined: 9-May 08 From: Racine, Wisconsin Member No.: 9,038 Region Association: Upper MidWest |
Are you sure it's completely compressed? The spring will get close but the needle should bottom out first. Measure it without the spring to see how far out it seats. Then measure it with the spring to see if it's holding you up.
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McMark |
May 10 2010, 09:24 PM
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#3
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
I've had that problem, but 1 turn out from seated won't be right anyway. You're going to be tweaking and adjusting those guys a bunch. Did you pull the idle screws to make sure the needle is still intact and unworn?
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Cevan |
May 11 2010, 05:50 AM
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#4
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Senior Member Group: Members Posts: 1,079 Joined: 11-December 06 From: Western Massachusetts Member No.: 7,351 |
The needles look new, no wear. After trying it without the spring, I put it back on and it does seat before the spring is completely compressed.
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VaccaRabite |
May 11 2010, 08:15 AM
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#5
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En Garde! Group: Admin Posts: 13,465 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
I had that problem on my current set of 40IDFs. I ended up cutting the last 1 or 2 coils off the spring. That allowed it to seat, and there is still tension on the spring when they are balanced.
I thought you wanted to start 2 turns off bottom, not 1. Zach |
Joe Ricard |
May 11 2010, 08:56 AM
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#6
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
1 1/2 turns off seated. once engine is warmed up and running SLOWLY turn in one screw till the engine starts to reduce RPM or changes tune. Then back it off 1/4 turn.
repeat for the other 3 barrels. if you are less than 1 turn out you are too rich on idle jet. more than 2 turns and you are too lean. |
jmill |
May 11 2010, 11:31 AM
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#7
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Green Hornet Group: Members Posts: 2,449 Joined: 9-May 08 From: Racine, Wisconsin Member No.: 9,038 Region Association: Upper MidWest |
1 1/2 turns off seated. once engine is warmed up and running SLOWLY turn in one screw till the engine starts to reduce RPM or changes tune. Then back it off 1/4 turn. repeat for the other 3 barrels. if you are less than 1 turn out you are too rich on idle jet. more than 2 turns and you are too lean. (IMG:style_emoticons/default/agree.gif) It does somewhat depend on your ET. If your using the F11 stick with Joes advice. If your running the F7 you can run a smaller idle jet due to the richer transition of the ET. After 2 1/2 I still go with a bigger jet. |
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