Cylinder Head Bolt torque problem

[TAMUmpower]

So I just replaced the head gasket and did the 3 stage head bolt process of 22 ft/lbs, 90 degrees, 90 degrees.

I had read that that should basically put a final torque spec of like 130-150 ft/lbs or so on the bolts. Just for kicks I put a torque wrench on a few of the bolts and they are all only at about 65 ft/lbs. How the heck did that happen?

Should I just try again or leave it since that was technically the correct process?

[rajicase]

Leave it. If you followed the correct sequence you are good.

[flyfishvt]

You're done. Move on

[ben4bama]

Take into consideration that you initially only torqued to 22 ftlb. Then consider as you did the 90 turns you compressed the gasket underneath each bolt next to the other in an evenly spread out manner so the first bolt you torqued was on an uncompressed gasket then as you came back around and torqued the one next to it you compressed the gasket a little more under the first bolt essentially reducing torque. Finally, you went from 22 ftlb to 65, you did 90 degree turns NOT 90 ftlb so why are you concerned about 65 ftlb ?

[TAMUmpower]

Yea looks like I'm fine. I found a thread where they used a dual angle/torque wrench and the final torque actually is 65 ish ft/lbs.

[tjm3]

Verify that you used new head bolts.

[TAMUmpower]

Lol yea of course

[tjm3]

Lol yea of course

Sorry, but always need to ask. You know why.

[E36BMW3series]

It matters a little bit if you oiled the bolts or not. I believe you aren't supposed to? Glad you found your answer though.

[ben4bama]

It matters a little bit if you oiled the bolts or not. I believe you aren't supposed to? Glad you found your answer though.

Actually you are supposed to oil the bolts as a lubricant. You just must remove any and all oil in the bolt holes that get filled with oil when you lift the head off.

[tjm3]

Posted just for interesting information.

Torque vs. Clamping Force (https://youtu.be/lsCyAvTqcNE)

[mboor]

Torque to yield head bolts. They stretch.

[tjm3]

Torque to yield head bolts. They stretch.

Yup, and once stretched they no longer provide the same clamping force.

And there are also torque to angle bolts and specs. What's the difference?

[mboor]

yes, they are one time use bolts. torque to yield, torque to angle, pretty much the same thing. the yielding point is where the stretching of the bold happens, and it can be a torque spec, such as 130ft/lbs, or it can be a measure of degrees of rotation, like a 90 degree torque.

[tjm3]

Nope. Torque to angle can be re-used as long as the bolt or stud has no thread damage (check procedure set by the manufacturer) or the stud or bolt has not exceeded it's pemanent stretch length. They're not all that common but I have run across them. Honestly, for what they cost I replace them anyway.