Manifold Torque

Jacksonlll

Well-known member
I have been using 45 ft.# like the red book says. Page 1-134.
Someone said that this was wrong in the red book. They were listing all the errors in Les's book. They said it should be 25 to 30 ft.#.

What is correct????
 
I can remember in auto mechanics classes years ago a student ask the same question and the teacher replied to tighten it till it breaks off and then back off one half turn ! Some how I became an ASE master mechanic.
 
I was told by a reputable engine builder, to torque to 20lbs. I looked at him cross eyed thinking he was crazy. So what can I lose I torque to 20 and everything is fine. Been 2 years now no leaks.
I’m happy
 
Like Pat says 45 foot lbs. probably won't hurt .Ford didn't list torque settings , so I've been told . Over tightening is what warps the exhaust manifold . I just use a 3/8 ratchet and a deep wall socket with common sense . After a few heat and cool cycles check and retighten . repeat as needed untill it seems to hold . When the exhaust manifold warps, the outer ends curl outwards . The exhaust manafold has no outer studs and nuts to hold the the ends flat when over tightened . Just my thoughts and experience .
 
As Purdey says, Ford didn't list torque numbers, it was just reasonably tight! About 30-35 lbs. But very important, Re torque or tighten several times after replacing the manifold. Ford mod A s are good at loosening up the heads and manifolds. Over tightening at first is not a solution. Coming back several times and retightening is.
Terry
 
Usualy when you retighten you will feel some minor looseness on some of the manifold nuts . After a few check and retighten they should settle in and hold . Most likely the manifold gaskets will shrink after a few heat cycles and retightenings . Its not about making it tighter each time. The manifold nuts just need to hold uniform tightness. Ford furnished a wtench that was used for head nuts & manifold nuts on one end , the other end fit the 3-X spark plug . The length of the mentioned wrench was supposeto give the proper leverage for the average person to tighten these nuts and spoark plug . This wrench ,came with the car.
 
I use 35 pounds and has worked well. There were some who used as high as 55 pounds. I think they were associating the size with head nuts which are working against compression. I agree that many statements in the "red' book are incorrect. Being in print makes it look official. One thing I stress is to tighten manifold nuts from the center outward and in stages. Nothing like trapping a bow and breaking the manifold to ruin your day. Of course you want the manifold to be on the same plane (flat, straight, etc.) as much as possible.
 
I can remember in auto mechanics classes years ago a student ask the same question and the teacher replied to tighten it till it breaks off and then back off one half turn ! Some how I became an ASE master mechanic.

We had a student in one of my classes that asked the teacher how many thousandths were there in an inch, the teacher replied, bloody hundreds of them.
 
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