#1  
Old 03-25-2026, 08:34 PM
kyle_blake's Avatar
kyle_blake kyle_blake is offline
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Most feedback in fb is suggesting my rear transfer slot is over exposed with symptoms I’m explaining. However the spring in diaphragm is not pressing the rod down hard enough so maybe I need to replace it a stiffer spring ? Wouldn’t want it flopping around . I dunno maybe the screw adjustment might tighten it up ?

Yes I heard that the pv or block off pv might have to thick of a gasket ? That I should try lining up metering block to body with out gasket and look for issues ? Same with main body to base plate . Also replace pv just to rule
Out . Power went out here so will
Have to try tomorrow . Thanks for suggesting the indent mark may be present .

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  #2  
Old 03-26-2026, 12:10 AM
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NeighborsComplaint NeighborsComplaint is offline
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Have you tried adding secondary idle air by adjusting the secondary throttle stop? That’s usually all that is needed to clean up the idle and restore function to the mixture screws.

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Old 03-26-2026, 01:29 PM
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Secondary transfer slot should not be exposed at idle. Starting point is to back off screw until it does not touch secondary arm. Then screw it in until the screw touches the arm, then go another 1/2 turn.

The IFRs looks large to me, but I can't see the actual restriction. Stock IFR on that carb is likely about .028 to .030".

Front transfer slot should be square at curb idle.

Starting point for 4-corner idle is to open the screws 1.25 turns. Close them in 1/8 turn increments for highest vacuum. A 4-corner usually ends up with idle mixture screws 1/2-3/4" turn open from seated.

What are LSAB sizes? 70?

High IFRs and 3 emulsions. Low speed AFR is going to be unstable. Cruise mixture is going to be rich. WOT will be about 13.1

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Last edited by chiphead; 03-26-2026 at 01:37 PM.
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