Diesel_Dan

Just lookin for opinions on weather it is ok or not to reuse the stock head bolts when reinstalling the head?

TIMMY22

no...................

ratsun

I would if they measure up. JMO

Clayten

It is not suggested to reuse u bolts when doing spring work. I am quite certain that heads bolts would fall in that category.

somis13

every time you tighten them, they stretch. head bolts is not the area to cut the budget.

GAmes

The Cummins head gasket kit comes with a gauge to measure the bolts. If it is a fairly stock install they will be fine. I replaced my headgasket at 195 k for a small coolant leak and re-used the bolts with no problem.

Crimedog

I agree with what GAmes said. Use the gauge supplied with the head gasket pack and if they've stretched then replace them. If they haven't, I see nothing wrong with reusing them. If Cummins says just to replace them if they are stretched according to the gauge, it is hard to disagree with them.

Diesel_Dan

Thanks guys, I am just going to order new bolts and be done with it.

Muddin_dude06

If your going to order new bolts depending on how much they are and how much you want to spend you could get some ARP or A1 headstuds, those are reusable and will help hold the gasket better.

Fueling around

This was a new bolt


Failed on re-torque.

96_12V

It's also true as the photo suggests that new bolts can fail. Remember to double check the grade of the bolt (likey 10.2 or grade 8) as you DON'T want that to be different. And re-torque properly only to the reccommended spec.

I heard a metalurgist say it this way - a bolt is a spring. When you consider how it's loaded and how the three major parts of the bolt (threads, shank, 7 head) are rated each for a percentage of the load, it's just plain astounding how much design criteria goes into simple fastner selection.

Also, most heads have recommended tightening sequence, follow that as well...good luck with your repair.

redramnc

Studs have more uniform clamping force than a bolt. More thread engagement in the block also means less chance of stripping as well as more uniform stress to the block around the holes.That is why torque plates on engine boring equipment use studs.

If you think about how a bolt head is forged versus a stud then you begin to see where the stress at the head shoulder is more variable than the stress at the stud nut. Granted, you are dealing with threads on the top of a stud versus solid metal but the strain vectors are more even with studs than bolts. Plus, I trust new stud threads alot more than heat-cycled block threads that may or may not have been perfectly cut when new.

Just some things to think about. If nothing else new bolts are cheap insurance.

Diesel_Dan

I was looking at spending about $130 for a head bolt set, how much do studs cost?

Crimedog

Studs will run you a little over $400 by the time they get to your door.

Diesel_Dan

On my budget I think that bolts are for me.