Author Topic: broken primary shaft butterfly screws  (Read 3902 times)

Offline FNG

  • Garage guy
  • **
  • Posts: 8
broken primary shaft butterfly screws
« on: September 22, 2013, 11:41:15 AM »
i have a 7044213  carb that i'm doing a budget build for a friend,and even after grinding off the staked part of the butterfly screws on the primary shaft and heating them with a small butain torch three off them snapped.anyone have any tips for extracting them?also would like some building tips,it has the large main air bleeds around .105  the engine is a mild 350 with headers.i was going to throw in some 72 jets and 44 tappered rods i have laying around,and use cliffs receipt 1 in his book.on a side note my pontiac qjet is running great with cliffs hp kit and tips from him and his book.

Offline Ethan1

  • Moderator
  • Qjet Hero
  • *****
  • Posts: 1148
Re: broken primary shaft butterfly screws
« Reply #1 on: September 22, 2013, 02:22:42 PM »
 You are more than likely going to have drill them out. You can go to the next size up and retap the holes. Try drilling in the center of the broken screw. I would say try a #8 or #10 bit and screw.
Ethan

1972 Chevelle

(oo______oo)

Offline FNG

  • Garage guy
  • **
  • Posts: 8
Re: broken primary shaft butterfly screws
« Reply #2 on: September 26, 2013, 06:57:39 AM »
thanks for the reply.i got lucky and drilled to .105 pretty much centered,so i tapped to 6-32  per a post i found here.i searched before posting too.but if any one has any tips or suggestions on this 7044213 carb,id like to hear them,instead of making another post.  went and looked at the 66 truck its going in and found its a small block 400,ebrock intake,headers,dual exhaust,not sure on cam,heads are stock iron.

Offline poncho2

  • Newbie
  • *
  • Posts: 4
Re: broken primary shaft butterfly screws
« Reply #3 on: October 03, 2013, 12:57:56 PM »
As far as the large bleed holes,  I just rebuilt a very similar Q-Jet (7044202) for my grandaughters truck and cliff sold me some drive in bleeds with I think .046 holes along with smaller jets and metering rods.  I haven't been able to test the carb yet because were waiting on a new gas tank to arrive,  but I expect the carb to run great on the stock 350 motor.

Offline Cliff Ruggles

  • Administrator
  • Qjet Hero
  • *****
  • Posts: 5418
Re: broken primary shaft butterfly screws
« Reply #4 on: October 09, 2013, 04:13:42 AM »
72 jets and 44 rods would be a poor choice for that carb number. 

Two ways to set them up, larger jets and smaller rods, or reduce the main airbleed sizes.

We can supply all the parts needed to go either way.  It will be very close with the parts we select for what you are doing.....Cliff

Offline poncho2

  • Newbie
  • *
  • Posts: 4
Re: broken primary shaft butterfly screws
« Reply #5 on: October 10, 2013, 11:14:32 AM »
finally got to test the carb on the grandaughters truck and it works just great.  I would recommend the smaller bleeds and smaller jets and rods as per cliffs recomendation.  This carb has much better throttle response off idle and makes much better power throughout the power range than previously.  the power piston spring he sold me was right on the money. 

Offline Cliff Ruggles

  • Administrator
  • Qjet Hero
  • *****
  • Posts: 5418
Re: broken primary shaft butterfly screws
« Reply #6 on: October 23, 2013, 03:24:41 AM »
Good news!....Cliff