Just checking once you take off your heads you shouldn't reuse the old headbolts. Is this correct? Is it because the old ones are stretched out??

 

I don't think that applies to Aeros. They have cast iron heads. You may be thinking of aluminum heads that use stretch bolts.

 

Aeros along with most production vehicles especially Fords use torque to yield one time only useage head bolts....

always replace with new....old ones will not torque properly and maintain proper head gasket clamping which will lead to leaks

from Ford Service DVD
Remove the cylinder head attaching bolts and discard.

 

I use to replace headbolts. They are not too expencive, but the broblems related with wrong head torq. are rather evpencove!

 

I stand corrected.
I've never seen this requirement before on cast iron but the Aero manual says to use new bolts.

 

It depends on the engine you have.

The 4.0L with their Torque-to-Yield head bolts will require new head bolts every time you open up the head.

However, the 3.0L is different. You can reuse the head bolts on the 3.0L once. The usual practice is to put a dab of paint on the heads of the bolts you reused, just so that the next guy who opens it up knows that he needs new ones when he sees the paint.

 

Why would you want to reuse them. I would just as soon replace the bolts. It is not worth fooling around with.

 

I agree. I wouldn't reuse the head bolts if I have a choice. However, other people might have financial constraints. In any case, if you can afford it, you should definitely spring money for a new set.

On the other hand, I have reused head bolts on a GM 350 cu in back when I was a poor student, and that didn't cause a problem.

 

I replaced the old head bolts on both sides with new ones during my 3.0 cracked head repair, and if I remember, it was only around $15.00 for all of them. So they're not too expensive, but all those $10, $15, $20, $50 costs sure add up quick when you're doing a big job like that...lol. But you would be better off in my opinion, if you used new ones.

M

 

from Ford Service DVD 3.0L engine
Installation
Install new cylinder head retaining bolts and hand tighten

Tighten retaining bolts in sequence as illustrated to 80 Nm (59 lb-ft).

Back off all bolts a minimum of one full turn (360 degrees).

NOTE: When the cylinder head retaining bolts have been tightened using this procedure, it is not necessary to retighten the bolts after extended engine operation. However, the bolts can be checked for tightness if desired.



Retighten the cylinder head retaining bolts in sequence in two tightening steps as follows:

45-55 Nm (33-41 lb-ft)
85-99 Nm (63-73 lb-ft)

3L is also torque to yield head bolts
set of AC Clevites are less than $20...less than another set of gaskets if there is a leak with old bolts

my moto, do it once only

 

https://engineparts.com/solutions/SS-VR-M-04.pdf

 

Well I always heard that Head Bolts are harden steel. Harden steel doesn't stretch....Unless they are using some crappy steel or making the bolts thinner.

When I rebuilt the two 3.0s I used the same bolts back. No Problems.

JaY

 

from Dana Victor Clevite

Issue:
Head bolts are elastic. Tightened and under load in the engine they are stretched.
When the load is released or when the bolt is backed off, the head bolt returns to its
approximate original length. All bolts or threaded fasteners have a yield point. When
the yield point is reached during the tightening process, the bolt loses some of its
elasticity and does not return to its original length when the load is released. It’s quite
common for engine manufacturers to tighten bolts to the yield point. Torque-to-yield
fasteners are found on domestic and import light-duty and heavy-duty engines.
Because the bolts may lose their strength and are pushed to their yield point after
thousands of engine operating cycles, original-equipment manufacturers (OEMs)
recommend the bolts be replaced any time they are removed.
Resolution:
Victor Reinz offers replacement bolts
and fasteners for both light-duty and
heavy-duty engines. Bolts are supplied
in sets and each set is enough for one
cylinder head. Our bolts and fasteners
meet or exceed the OEM specifications.
Tightening instructions are included in
each package.
Application:
Victor Reinz head bolts and fasteners
are available in more than 80 part
numbers.
To make your job easier, Victor Reinz has introduced a new “torque-to-yield logo,” which will appear on our head gasket
packaging and in our catalog. When you see the logo, that means the torque-to-yield head bolts must be replaced when a
new head gasket is installed.
Typical Bolt Failure