My Haynes book is strange it gives 3 steps to torque the Head Bolts.. Step 1 35 ft.lb. Step 2 55 ft.lb. I stopped there until I find out something. Step 3 says to turn the bolts after step 2 about 90 degrees More.. what the Hey?? why can't they just give me another Torque. these are the 7/16 d bolts..Thanks for your help
what year 302? sounds like you have TTY specs.
I would say it was a 88 5.0 EFI
Cylinder head bolts 65-72 ft.-lbs.
^^^^^^^^^^^^^^^^^^^^
Main cap bolts 60-70 ft.-lbs.
Outer main cap bolts, 35-40 ft.-lbs.
Connecting rod bolts 19-24 ft.-lbs. (40-45 ft.-lbs. for 289 HP Boss 302)
Cylinder head bolts 65-72 ft.-lbs.
Rocker arms 17-23 ft.-lbs.
Intake manifold bolts 23-25 ft.-lbs.
Oil pump bolt 23-28 ft.-lbs.
Cam bolts 40-45 ft.-lbs.
Cam thrust plate bolts 8-10 ft.-lbs.
Harmonic damper bolts 70-90 ft.-lbs.
Flywheel/flexplate bolts 75-85 ft.-lbs.
Pressure plate bolts 35 ft.-lbs.
Front cover bolts 12-15 ft.-lbs.
To evenly tighten the head down first do step one to all the bolt then step 2 then step 3 usually there are 2 steps example (40-60 foot lbs) means first tighten all bolt to 40 foot lbs then retighten at 60 lbs from the center out.
Thanks so much that is what I was looking for..
Engine Photo's under Bronco II, Link below
My Haynes book says Step 1: 55 to 65, Step 2: 65 to 72 (page 78). Are you using the same book (#1338)? It's possible a later printing is using a different method, with a lower initial setting of 55 lb/ft (to get everything equalized) plus a calculated crush value (
x degrees with thread pitch
y gives gasket crush
z), similar to, but not the same as using actual Torque To Yield bolts.
Wish I had some 4 bolt mains..
I would use the Haynes proceedure. They have learned how to get a more accurate clamping pressure since these cars where built.
For example, here is the head bolt proceedure from the '01 Crown Vic shop manual:
Step 1: Tighten to 28-31 lb-ft
Step 2: Tighten an additional 85-95 degrees
Step 3: Loosen the bolts a minimum of one full turn (360 degrees)
Step 4: Tighten to 28-31 lb-ft
Step 5: Tighten an additional 85-95 degrees
Step 6: Rotate an additional 85-95 degees
That really sounds strange to Me rotating 85 to 90 degrees should have a foot Lb. torque . 01 isn't that the 4.6 with the overhead cams ? , I see what you are saying about the fact they are still using that proceedure..
I wouldnt use those 4.6 specs there TTY and will cause issue's with your TTS bolts (yes there is a differance) and they do not apply to your 5.0
After trying to educate myself I see that Sleeper is correct. You are never too old to learn something. Measuring how many degrees the bolt turns does only apply to TTY bolts.
When bolts are stretched in their "elastic" range they will return to their original length when loosened. (Standard bolts)
When they are stretched beyond the "elastic" range to the "plastic" range they will not return to their original length. They cannot be reused. (TTY bolts)
Is it possible that the 3.8 bolts are TTY? Maybe the Haynes manual is giving the 3.8 specs?
The '84 shop manual says to always use new bolts for the 3.8.
It has a four step torquing sequence, then loosen them and do the torquing sequence again.
This sounds similar to the TTY proceedure.
For the 5.0 it has a two step proceedure. Does not say to use new bolts.
Step 1: 55-65 ft-lb
Step 2: 65-72 ft-lb