Head bolt torque totals.
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New User
Joined: Aug 2008
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Head bolt torque totals.
I just put the heads on my 88 2.9L. My question is after the 90 degree turn what is the total amount of torque I should have at each bolt. The torque wrench I used totaled out and would no longer give me a reading (digital). I ended up doing the rest with a different wrench but was just wondering if any of you guys knew what the final value was so I can check them.
Thank you and all input is greatly appreciated.
Thank you and all input is greatly appreciated.
Elder User
Joined: Dec 2007
Posts: 739
Likes: 1
There is no final ft. lbs of torque listed for a "Torque to Yield" cylinder head bolts. The last torque spec listed should have been something like 51-55ft lbs of torque, followed by waiting about 5 minutes---- Make a mark at the 12:00 position on each bolt head, and turn it 90degrees in the correct sequence. (12:00 to 3:00) following the instructions EXACTLY.
So....there really is no final---FINAL torque anyone can really offer for a torque to yield set of cylinder head bolts? You're doing the last torque at about 55ft lbs...and that extra 90degrees after the 5 minutes of waiting? That is causing the bolt to tighten more--and makes it "Stretch" the bolt.
Have no clue as to why they used this method? let's face it--spending about 40 bucks on a new set of head bolts EVERY time you have to tear into it? Yeah---big pain. These buggers are single use only.
However, there really is no answer to the question as to the exact amount of torque is required to hit that 90degree mark? At least nothing listed in any of the service manuals we have access to. I'm sure Ford probably has some specs used at the engine assembly plants, but who knows?
For what it's worth? After the 55 ft lbs, and the 5 minute wait with ours? I used a 2' long breaker bar with a 1/2 drive T55 socket. Yeah...it probably would have maxed out a normal torque wrench? (we had to install new cylinder heads on ours on Sunday)
S-
So....there really is no final---FINAL torque anyone can really offer for a torque to yield set of cylinder head bolts? You're doing the last torque at about 55ft lbs...and that extra 90degrees after the 5 minutes of waiting? That is causing the bolt to tighten more--and makes it "Stretch" the bolt.
Have no clue as to why they used this method? let's face it--spending about 40 bucks on a new set of head bolts EVERY time you have to tear into it? Yeah---big pain. These buggers are single use only.
However, there really is no answer to the question as to the exact amount of torque is required to hit that 90degree mark? At least nothing listed in any of the service manuals we have access to. I'm sure Ford probably has some specs used at the engine assembly plants, but who knows?
For what it's worth? After the 55 ft lbs, and the 5 minute wait with ours? I used a 2' long breaker bar with a 1/2 drive T55 socket. Yeah...it probably would have maxed out a normal torque wrench? (we had to install new cylinder heads on ours on Sunday)
S-
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