Help!!
 
I have over tightened my head bolts.
 
When I was torquing down my head bolts I took them to the specified torque. Once done the manual tells us to turn the head bolts an additional 90 degrees for the TTY spec. I accidentally set them to 180 degrees. Is this going to be an issue? Should I get new head bolts? None of the bolts snapped or felt weird while doing this. I tightened them all in sequence and didn't do them the whole way in one go, more like I set them to torque then turned them 45 degrees at a time in sequence until I got to 180 degrees.
 
Will my headgasket be too squashed? I am almost done with the engine rebuild and the thought of doing it all again is very stressful.
 
Please help.
 
Thanks.

Whats a set of head bolts going to cost you now versus when/if one of them lets go in a week/few years?
 
Imagine replacing one of them when the head gasket has failed down the track.
 
I'd replace them. Much easier to do now.

Maybe 'banner' is correct, but I'm not so sure I would worry about it that much, after all oem head bolts do stretch, and 1/4 extra turn doesn't seem like all that much too me. Certainly can't see it hurting the hg, and I have a hard time believing that Toyota engineers would have created specs so close to the fail point of the affected parts. But that's just me.

Agreed, it's only 1/4 turn extra and the bolts felt good all the way. If it fails again it'll be a good excuse to put a Gen 3 in. Thanks for the reply.

I've decided I'll get new bolts, it's a small price to pay for piece of mind. Thanks all

Problems could lie with over crushing the head gasket aswell.
 
If it was me I'd leave the bolts alone, but it's your engine.

Leave it! Don't touch it now

You'll also need a new gasket if you are going to replace the bolts and re-torque

I am getting different opinions on this from multiple different forums and after much research about tty head bolts i believe that the bolts stretch past their maximum clamping force and actually become weaker. Therfore applying less pressure on the HG. Putting new bolts in at the correct torque and angle will apply more consistent and even pressure to the HG. I have only removed the bolts and left the head in place. The head has not moved in relation to the block so the current seal should be intact. Applying the correct torque and angle should add more pressure to the HG giving an even better seal. I have read that some people actually torque their head bolts then loosen them and then retorque them. They believe this gives a better seal and prevents differences in the torque of each bolt.
I have already removed the bolts and they are very obviously deformed. Therfore they were unable to exert too much force on the HG. I just can't afford another HG. Or have the patience to pull it all apart again. The engine has not been started yet so no heat has been applied. I've committed to replacing the bolts as this is the easiest course of action to prevent the bolts breaking while driving. I'm going to run like this and I'll report back my findings once it's back in the road. Maybe it'll help someone else. There is very limited information regarding this issue for the 3sgte. People have done this on other engines and seem to have had no issues once the new bolts were installed. I'm praying for that on this engine.

The help i have received from everyone on this site is second to none. I'm happy to be a part of the community.

Regards

Realistically, either course of action probably isn't any better than the other. We're not talking about a seriously modified engine here.
 
I would say re-torque the bolts after a couple of heat cycles just for piece of mind, but it isn't feasible since they give you degrees instead of ft-lb/NM and the bolts would have stretched anyway.