69 427 tripower problems
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
Burning Brakes
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
set your WOT fuel mixture first, then set the float levels. float level is extremely important and setting it incorrectly will have a dramatic affect on idle. do not set the level too high.
obviously make sure everything is clean and no vacuum leaks first, etc.....
Racer
Joined: Dec 2008
Posts: 297
Likes: 19
From: arlington TX
Hi,
If it runs at rpm over 2000 (that's about where the idle circuit quits and the main circuit takes over), the idle circuit on the center carb is plugged. Take out each idle mixture screw (motor not running) and squirt carb cleaner in there. Should come out of a hole on the side of the carb throat under the throttle plate and out of the idle air bleed hole (front ledge of the carb inside the choke tower, facing up). There are 4 holes there - the 2 center ones are main jet bleeds and the 2 outside ones are idle bleeds. You may want to put your hand or a rag over the bleed hole or carb cleaner will go everywhere. Both places should flow freely. If they don't, make them. Afterwards, put each idle screw back in and back out about 1 3/4 turns. That will get you in the ballpark and adjust from there.
Good luck.
walt z.
If it runs at rpm over 2000 (that's about where the idle circuit quits and the main circuit takes over), the idle circuit on the center carb is plugged. Take out each idle mixture screw (motor not running) and squirt carb cleaner in there. Should come out of a hole on the side of the carb throat under the throttle plate and out of the idle air bleed hole (front ledge of the carb inside the choke tower, facing up). There are 4 holes there - the 2 center ones are main jet bleeds and the 2 outside ones are idle bleeds. You may want to put your hand or a rag over the bleed hole or carb cleaner will go everywhere. Both places should flow freely. If they don't, make them. Afterwards, put each idle screw back in and back out about 1 3/4 turns. That will get you in the ballpark and adjust from there.
Good luck.
walt z.
Burning Brakes
Joined: Jul 2015
Posts: 823
Likes: 57
From: Austin TX
I had a Holley once that wouldn't idle. Wasted a lot of time working on it, turned out the PO had installed the wrong metering block gasket. It looked virtually identical to the correct part, but one or two of the holes weren't there (or were misaligned, I don't remember exactly from 35 years ago). Anyway, maybe the guy who rebuilt the center carb used the wrong gasket. Just something to consider.
Last edited by 454Luvr; Jan 13, 2016 at 04:23 PM.
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