Torque Sepc for installing carb on intake manifold with phenolic spacer?

Discussion in 'The Venerable Q-Jet' started by CyberT, Sep 15, 2016.

  1. CyberT

    CyberT Silver Level contributor

    IIm on my way to install my QuadraJet + phenolic spacer with ARP studs.

    ARP recommend 24 or 28 or 32 ft./lbs on their 5/16 bolts. Dont understand their page.

    Service manual recommend 10-15 ft.lbs

    Should I pull 10-15 ft.lbs even now with the spacer?
     
  2. maddoggy

    maddoggy Well-Known Member

    You are still using gaskets and you only added an aluminum spacer. The torque should only minimally change due to added stud length, maybe 2 lb. ft. total. ARP fasteners are just wasted money in this application. Any graded stud the proper length would be fine. Go with the service manual specs +2. To be honest, I have never tightened these with a torque wrench ever. Just good and snug by hand but not overdone.
     
  3. scubasteve455

    scubasteve455 Well-Known Member

    I have heard of people and Good mechanics over torque the longer front bolts. Stress cracking carb housing. What a nightmare. Putting my moroso .5 spacer when I get my Q-jet back together. Full rebuild. Installing Nos GM heat Sheild also got longer ARP bolts . I will be torq them little bit more than what the manual says too! Great thread. Glad I caught it. Hope me putting in spacer. That I have no regrets. Hope it responds well
     
  4. hugger

    hugger Well-Known Member

    Use a washer on the front bolts, and just go a 1 to 1.5 turns from the bolt bolt seating , evenly IE corner to corner.
     
  5. ctlikon

    ctlikon Well-Known Member

    Yes, do as hugger suggests as anything more will most likely warp the carb air-horn and body up front. I have never seen one cracked though. This is a common mistake/issue with Quads.
     
  6. scubasteve455

    scubasteve455 Well-Known Member

    Thank you ! Putting carb back on car next week. I'm no wrenching wizard . Good to now. I needed that insight
     
  7. CyberT

    CyberT Silver Level contributor

    I turned 1 1/4 turns on all which felt scary.
    It felt like I had to use more force on the short ones to achieve this.
    Making me wonder what would happen if I used a torque wrench and it would stop earlier on the short studs. Which would make the carb be most leveled, same amount of turns, or same amount of torque.
     
  8. Jolly-John

    Jolly-John Well-Known Member

    I like the idea of using washers on the two front bolts. The factory shop manual lists 13 ft. lbs. (156 inch pounds) torque on the four carb mounting bolts. I wonder how that equates to hugger's 1 to 1.5 turn tightening suggestion.

    Do you guys with more carb experience than me think the 13 ft. lbs. spec is too tight for a Quadrajet (possible air horn warping)? Thanks. John
     
  9. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    I can't believe this thread actually exists:grin: For crying out loud, why torque something like a carburetor mounting bolt? It just needs to be snug.:Dou:
     
    matt68gs400 likes this.
  10. maddoggy

    maddoggy Well-Known Member

    :TU::gp::beer
     
  11. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    How many bolts have you stripped now? I can see using a torque wrench on cylinder heads, intakes, connecting rod, main bearing, and other critical engine parts. I don't need a torque wrench for timing covers, water pumps, thermostat housings, carburetor mounting, spark plugs, and other small bolts. I just go by feel, snug them up enough that they aren't loose. Sounds like OCD to me.:grin:
     
  12. CyberT

    CyberT Silver Level contributor

    (my) Life sure was easier when I didn’t know what a torque wrench was and just pulled as hard as I could and was happy with it. :laugh:
    (Volvo survive everything)

    To be honest, I have second thought about the 1 turns I made on the carburetor nuts, worried that it was too much. But I don’t know if it will mess up the gaskets if I go back to 1 turn.
     
  13. CyberT

    CyberT Silver Level contributor

    What will happen if someone torque too hard?
    - Internal gasket fail, just replace it?

    Engine didnt start, forum thinks its the ignition. Fuel leak on the line and maybe first startup flooding. Fuel cloud came up from overflow pipe on carb two times. But the sparkplugs werent wet at all.
    When I think flooding, I think wet sparkplugs. Should my dry sparkplugs be a sign that I didnt over torque?

    In short; how do I analyze if I failed installing it by hand?
     
  14. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    Sounds like the distributor isn't in right. It has nothing to do with the ill advised use of a torque wrench for tightening down your carburetor unless you managed to strip the stud. Not sure why you continue to make simple maintenance into a complicated mess that produces endless threads with no resolution in sight.:Dou:
     
  15. matt68gs400

    matt68gs400 Well-Known Member

    Everybody here knew absolutely nothing about motors at one time in their life. It's harder and harder to find people who know much about engines and mechanical things these days. Thank God we have these forums.
    Anyways, keep asking questions here. It's the only way to learn.
     
  16. HotRodRivi

    HotRodRivi Tomahawks sighted overseas

    For you Cyber T, I would absolutely without a doubt 100% you better believe it hands down on the table with a peanut butter n jelly sandwich And gravey, recommend going to a wrecking yard with a socket set wratchet and find all the bolts you can tighten, tighten them and feel them squeeze and stretch and pull the threads out. That's over torqued. You need to know that threshold. Then run some down with your hand choked up on the wratchet snug, then half a quarter turn is about 10 to 15 ft lbs, a quarter is close to 20.
     
    12lives likes this.

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