head bolt torque?

xwrench3

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I have the wonderful job of replacing the head gaskets in my 3.8. this is not my first rodeo for changing head gaskets, but it is on this engine. Mine is the 94 model. i have looked up the head bolt torque specs. and I have to say that what I am finding seems like a lot of difference between the top and bottom bolts. It seems really strange that there is so much difference since all of the bolts are the same diameter, and the top bolts only a little bit longer than the bottom ones.

Step 1
15 ft. lbs.
Step 229 ft. lbs.
Step 337 ft. lbs.
Step 4NOTE 1
Step 5Long Bolts29-37 ft. lbs.
Short Bolts7-15 ft. lbs.
Step 6NOTE 2
NOTE 1Loosen 2 or 3 turns (DO NOT loosen all the bolts at once, from here on
do this step and the next ONE BOLT AT A TIME.
NOTE 2Tighten an additional 90°

is this really correct? If the bottom bolts were one size smaller, it would make more sense. but they are all 7/16" ALSO: I KNOW that I have to replace all of the head bolts, and I have new ones in hand. but there was no instructions except to make sure to use a sealant on the bolts that go into the coolant passages. should the threads on the rest of the bolts be lightly lubricated? what about under the built in washer (where the shoulder rides against the head)?
 

96blak54

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im not familiar with 3.8l headbolt torque specs or sequence, but i will say its process is not uncommon. The bolt diameter and bolt length can change a bolts holding capabilities.

I would have done the same as you did. Source out instructions, specs and knocked it out. I recommend lubricating the threads ans well as the washer under the bolt head. If instructions call for sealant on a bolt, thats kinda of weird, but follow instructions.
 

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