Had new ARP's and gasket put in about 6 months ago, yesterday noticed a dent in hood and discovered 2nd bolt back from front on exhaust side missing. It apparently came out with enough force to put a dent in the hood. Any ideas why and what it is going to take to fix and keep from happening again? I think it happened when wife was driving and I seriously doubt that she was pushing truck very hard. She doesnt recall hearing anything.

 

If you are good with a drill and an ez out you might get it without pulling the head. The key would be to center punch it as close to center as possible and as deep as possible before drilling. Suprising that happened unless whoever installed them didnt follow ARPs instructons or Cummins' sequence. I dont see a need for studs unless you're pushing 50+ lbs of boost IMO.

 

If the stud failed under normal torque, it could have "sprang" up and hit the hood. I also suggest using a left hand drill bit. If you can get the drill bit to "hang" or "bite" you might back the bolt out.

 

I was thinking the "sprang theory" hope to have it back from shop by end of this week. Shop is making good on the work even tho it was more than 12k miles and 12 months since he last worked on the head, gotta love having good relationship w/ shop.

 

yeah! good relations/warranty is pricless

 

Those head bolts i belive are supposed to be tourqued and losesened like 3 times then a final torque applied. Some shops just over touque the bolts to begin with so they don't have to take all the time to do it right. It does add a lot of time doing it right, i've done it. That may be why it broke. But then again an arp should be able to take a little over torque.