Author Topic: 7043262 air bleed screw spec?  (Read 1425 times)

Offline mcx

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7043262 air bleed screw spec?
« on: November 13, 2020, 10:55:36 AM »
The airhorn located air bleed adjustment screw (under the triangle lock tab), how many turns from bottom is it set?  Thanks.

Offline Kenth

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Re: 7043262 air bleed screw spec?
« Reply #1 on: November 13, 2020, 12:00:23 PM »
Depends on Rochester made or Carter made #7043262.
I have found Rochester made units uses #71 pri. jets with #41 primary rods, .083" upper main air bleeds and upper main air bleed screw 1/2 turn up from lightly seated.
Carter made units uses #74 pri. jets with #44 pri. rods, .050" upper main air bleeds and upper main air bleed screw 1 turn up.

Offline mcx

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Re: 7043262 air bleed screw spec?
« Reply #2 on: November 13, 2020, 03:00:00 PM »
Thanks Kenth.  What do you suggest based on these numbers?
It's a Carter stamping with 71 jets and 41 prim rods...CR sec rods.
Main bleed  .0725"    upper idle bleed(airhorn) .0525"
Idle tubes .033"    IDCR  .041"  Lower idle bleed .0625"   
 Lower Main bleed .0625"
Idle mixture holes .108"    Idle air  bypass  .108"
« Last Edit: November 13, 2020, 03:13:51 PM by mcx »

Offline Kenth

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Re: 7043262 air bleed screw spec?
« Reply #3 on: November 14, 2020, 07:09:50 AM »
Most #7023262 i have taken measurements from has .037"-.038" idle tubes, .045"-.047" idle downchannels, .055"-.056" upper idle air bleeds, .069"-.070" lower idle airbleeds and .070" main air bleeds in bowl. .110" x 2 idle air bypass in plate and .092" added from the hot air choke channel.

If the carbs sits on its original engine i would start with .038"-.040" idle tubes, .052"-.055" IDCR, DA or CE secondary rods with a K-N hanger. Seat the main air bleed screw and use #73 jets with #41-#43 rods. You may open the screw some if rpm decreases at the 2200 rpm tip-in test.

HTH

Offline mcx

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Re: 7043262 air bleed screw spec?
« Reply #4 on: November 15, 2020, 05:28:01 AM »
Thank you....I'll set it that way.