Author Topic: Metering Rod and Jet Combos  (Read 6782 times)

Offline Ethan1

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Metering Rod and Jet Combos
« on: October 16, 2016, 03:38:10 PM »
 Hey Guys,

 I know a lot of people have asked what my secret is, well here it is.

 Look up the part number for the jet (jets are always decoded using the last two digits of the part number), metering rods and metering holder (which is always 7034512 "K") and decode them using these pages:

 http://www.oldengine.org/unfaq/leadfoot/qrodpri.htm for Primary Metering Rods
 
 http://www.hioutput.com/tech/qjetrod.html for Secondary Metering Rods

 Let me know if you need any help!

 FWIW, this only works from 1967-1980.

 Ethan
 
Ethan

1972 Chevelle

(oo______oo)

Offline Ethan1

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Re: Metering Rod and Jet Combos
« Reply #1 on: October 16, 2016, 03:43:35 PM »
 Part numbers can be found in the big AC Delco books or at:

 http://newagemetal.com/
Ethan

1972 Chevelle

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Offline Ethan1

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Re: Metering Rod and Jet Combos
« Reply #2 on: October 30, 2016, 07:52:46 AM »
 Adding a website with part numbers for the earlier primary metering rods as well:

 http://www.gmcmi.com/wp-content/uploads/2014/05/Quadrajet-Carb-Primary-Metering-Rods.pdf

  8)
Ethan

1972 Chevelle

(oo______oo)

Offline Ethan1

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Re: Metering Rod and Jet Combos
« Reply #3 on: January 15, 2017, 02:11:09 PM »
Part number 17111346 was used on several of the mid-80's Q-Jets.

Here is the items in that kit:

.075" Primary Jets
61S Primary Metering Rods
EF Secondary Metering Rods

HTH, Ethan!
Ethan

1972 Chevelle

(oo______oo)

Offline Ethan1

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Re: Metering Rod and Jet Combos
« Reply #4 on: January 16, 2017, 04:25:20 PM »
 Here is another kit 17067147:

 .072" Primary Jets
 51M Primary Metering Rods
 DR Secondary Metering Rods
 33797 Secondary Hanger
Ethan

1972 Chevelle

(oo______oo)

Offline Ethan1

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Re: Metering Rod and Jet Combos
« Reply #5 on: January 16, 2017, 04:31:24 PM »
 http://www.gmpartswiki.com is a great website for the '81-Up Qjets.
Ethan

1972 Chevelle

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Offline Ethan1

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Re: Metering Rod and Jet Combos
« Reply #6 on: February 07, 2017, 04:12:34 AM »
 PLEASE READ: 1981-UP Quadrajets used a part number called a metering rod and jet kit part number. They DID NOT put specs of a Quadrajet carb number (81-UP) in the manual. Just one simple kit part number. In that kit, it contained the primary metering jets, primary metering rods, secondary metering rods and secondary hanger. If you by chance run by an AC Delco metering rod and jet kit, please let me know, so I can jot down the info on here.
Ethan

1972 Chevelle

(oo______oo)

Offline unruhjonny

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Re: Metering Rod and Jet Combos
« Reply #7 on: February 21, 2017, 11:23:44 AM »
interesting.
Thanks for sharing this Ethan!
I have a couple older MPC's, but decoding the secondary metering rods, and hangars has always been a mystery to me...

Offline Ethan1

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Re: Metering Rod and Jet Combos
« Reply #8 on: February 21, 2017, 11:45:01 AM »
interesting.
Thanks for sharing this Ethan!
I have a couple older MPC's, but decoding the secondary metering rods, and hangars has always been a mystery to me...

 Cliff also lists the secondary metering rods part #'s in the back of his book, too. FWIW ;)
Ethan

1972 Chevelle

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Offline Ethan1

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Re: Metering Rod and Jet Combos
« Reply #9 on: February 22, 2017, 02:46:30 PM »
Here are some part numbers for youz power piston springs:

3Hg spring 7029922
3Hg spring 7037851
4-8HG 7036019
6Hg spring 7037305
Ethan

1972 Chevelle

(oo______oo)

Offline sep455

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Re: Metering Rod and Jet Combos
« Reply #10 on: March 21, 2018, 08:48:52 AM »
I'm a little confused, if I want to re-jet my carb richer, and go from a 68 jet to a 70 jet, then how do I choose the correct corresponding primary rod?

Offline Ethan1

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Re: Metering Rod and Jet Combos
« Reply #11 on: March 21, 2018, 12:52:28 PM »
I'm a little confused, if I want to re-jet my carb richer, and go from a 68 jet to a 70 jet, then how do I choose the correct corresponding primary rod?

Do you have Cliff's book? You basically want to go with
a size smaller metering rod then. If you were leaning, then a size bigger. It's all about the size of the jet and how much that metering rod fills up the hole, that determines if you're leaning or richening it. Get Cliffs book and look at the metering rods and there corresponding sizes.
Ethan

1972 Chevelle

(oo______oo)

Offline 7228Sedan

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Re: Metering Rod and Jet Combos
« Reply #12 on: September 22, 2018, 07:02:31 PM »
In case anyone is interested:

Delco metering kit 17078767:

70 jets
42 primary rods
CL secondary rods
K hanger

Also packaged as Mercruiser  Quicksilver part 1397-8583

Application 454 inboard standard output 340HP

Offline Jamesediny

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Re: Metering Rod and Jet Combos
« Reply #13 on: October 12, 2018, 08:41:16 PM »
I believe that you need to write more on this subject matter, it might not be a taboo subject but generally people don't speak about these topics. To the next! Cheers!!

Offline monty

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Quadrajet 17058229 carburetor
« Reply #14 on: February 15, 2020, 03:00:49 PM »
I could use some advice/help/suggestions here. I grew up in the 70s with carburated cars although I never really got deep into the rebuilding of them. I have two Quadrajets which I have rebuilt recently and tore back apart more than once because I cannot get my 78 chevy pickup to idle very well. I Just finished a forth install today and got it running. After it warmed up it stumbled some for a bit then it settled down.I set both air screws at 2 turns initially and after warmed up and choke opened I reset them. I turned the driver side jet all the way in and the engine remained running at the same speed with no real change in idle. There is a slight miss noticeable while idling. It Seems to accelerate fine and sounds good with no missing. Thank You for any suggestions   Monty