Replacing Head Gasket on a 4.6 2003 Ford Expedition. The Haynes Manual and Felpro instructions have the following:

Step 1) Torque to 29-32
Step 2) Turn an additional 90deg
Step 3) Turn an additional 90deg

My question is when I do the first step and Torque to 30ft-lb, do I just torque it down once and then the next time I do the 90deg turn? Because by the time I am done with bolt 10, bolt 1 will not be at 30ft-lb, its pretty loose now. Or do I go back and make sure all the bolts are at 30ft-lb which may be a few checks on each bolt and then I do the 90deg turns?

 

I always double check em to make sure they're all at 30 then move on to the next step. Btw you are using new bolts right? If not those specs count for nothing.

 

Yep, new bolts. Heads back from machine shop to make sure they where flat and even pressure tested them. Just wanted to make sure since this is a job I do not want to do ever again. Tks Rock Krusher, its what I thought.

 

They are stretch bolts.

torque all them to 30ftlbs
mark 12 oclock position on the bolt head with a dot of white out
turn 90*
turn 90*

white out helps as a visual reference, so there's no doubt if you turned it far enough

 

Yes to what Patman and Crusher said. However new bolts have to be pre stretched. Perform the initial torque sequence then loosen and retorque all bolts using the 30-40 torque and two 90 deg. sequence.

(Used bolts) We used a 40 ft lbs initial torque then 90deg on all bolts then back and 90 deg on all bolts again using the correct order starting in the middle of the head and working outward as they were already pre stretched. (New bolts) 30-40 ft lbs then 90deg in order then loosen all bolts then perform final torque 30-40 lbs and both 90 deg rotations in correct order.

So after pre stretch on your new bolts and now performing final torque you torque each bolt in order 30-40 ft lbs. then go over each bolt again performing 90 degs in correct order, then over each bolt again using 90 degs in the same correct order.

 

I've never heard or tried "prestretching" they are designed to stretch as you install them, thats exactly why they are limited use, and why the torque is calling for degrees and not just a one time flat ftlbs rating.

 

Despite what some may say they are reusable and yes when new they should be prestretched. In fact the robot that torques the head bolts during assembly runs the bolts down and then loosens them only to apply the final retorque.
I have reused head bolts on hundreds of these engines (test engines) without any problems. In fact my 97 4.6 has all original head bolts even though I change both head gaskets. We always prestretched the new head bolts during hand assembly of new engines. We also tested engines with head bolts that were reused several times, running 300 hr FIE durability tests without head bolt failure. I am not even going to tell how many times we tested these head bolts during testing with the bolt manufacturer before we achieved failure because you won't believe it and I'm not going to lead someone to believe they should attempt it with their vehicle. If in doubt use new bolts.

 

I just dug a Ford 543 Procedure (engineering) out of my files. Here are the directions right from Ford Dearborn Engineering for Modular Cyl head bolt torque.

Service and Optional Production Method;

1.Install cyl head assembly over dowels.

2. A. Install M11 bolts 37-43nm
B. Rotate (tighten) all bolts 85-90deg.

3. Back out all bolts a minimum of one full turn (360 deg)

4. Torque all bolts in sequence as follows:
A. Torque all bolts 37-43nm
B. Rotate (tighten) all bolts 85-90deg
C. Rotate (tighten) all bolts an additional 85-90deg.

 

Straight out of the Ford manual 2006 5.4 3v

From the removal section:
From the install section:

 

You guys are nuts on bolts, -to much stress for me, - I just stop tightening when the air compressor turns on.

Out of beer beer, nighty night

 

Then you do it your way and I'll do it mine... I have hand built and disassembled many hundreds of these modulars since 1988 even prototypes before modular production, at Dearborn and the factory. I was one of the guys on the dyno testing project for these head bolts working with the manufacturer. Do what they tell you in the service book.... I quoted you the actual Ford engineering procedure that we had to use at the factory.
Just telling you from over 20 years of actually building these engines. I understand what you are trying to explain and I don't blame you but I also am aware that in the service manual it tells techs that they have to use the Ford cam retaining /locking tool during the timing procedure. I wrote the method we developed for setting timing which did not require any tools but Ford wanted to make money selling dealerships the tools for $800.00 a pop so my procedure never was published and that's the only reason....fact! The book is full of procedures that can be performed in a much better fashion just ask any of the dealer techs out there and if I was a bolt manufacturer I would tell everyone they need new bolts everytime they changed a cyl head as well.

 

I'd put money on BOTH instructions are correct. Variables exist, most likely more than we are aware of here; in total anyway. Rather than list the many that comes to mind, I'd extend my search for all/any TSB instructional's from the manufacturer that may exist. Whether it's simply a supplier/spec change or perhaps it's an economical difference with one another's given position in the field. The equation can change and this happens allot in this area, with many different things. When failure percentage is so minute, the instructional's favor the practical side of things for the manufacturer. Just to sample, I hope you get my meaning.

The bolts may indeed be identical. For the SAME engine, instructions may vary per operator/installers field once and after variables have been weighed. Not sure how else to explain, but I am sure it happens allot.

EDIT: I was going to look thru the TSB's real quick, until I realized that it wouldn't help in this case. Since TSB's are solely a Tech directive.

 

All that said, personally I'd lean toward the DYNOTECH response. Since all that is put on paper,- was down the hall and to the right.

 

We can agree to disagree then. Not bitter at all, and maybe that's the "old" way of doing it on the older engines?


I'm A.S.E. Master tech, and have worked for several different dealerships and different manufacturers, and have done probably 50ish head jobs in my career so far, including one in my driveway right now.

 

I think you hit the nail square on the head jbrew. They will always err on the worst case scenario which is the right thing to do.

Patman no problem here. I have the highest respect for you guys and your abilities and I'm not pretending that my way is the only way by any means.
take care.....p/s I'm not that old...LOL