I'm installing Thorley Tri-Y headers on my 2005 2500HD 6.0L. The driver's side rear exhaust manifold bolt has been broken for awhile. It wasn't broken flush with the heads so I wasn't too worried about getting it out. I was working it out with vice grips when it snapped off flush with the heads. It had turned 2-3 turns before it snapped. I cannot drill it out since it is too close to the fire wall.

Will I do damage to the new headers by running them temporarily without that bolt? I don't have time right now to pull the heads to extract the snapped bolt properly. I plan on swapping cams so I'll probably pull the heads at the same time and maybe swap to 243 heads??

Let me know.

 

If wont damage anything but it will leak and it will throw your o2 sensor readings off resulting in a rich condition.

 

Weld a nut to the stud and turn it out. If it is broken beneath the surface weld a tit up to reach the nut. In Canada this happens all the time with the extreme cold/heat cycles. It doesnt hurt the aluminum.

 

Same things with mine, caused a slight leak but the popping sound was really annoying. After a year and a half, I finally had a shop take it out; took a drill and HeliCoil. Wasn't enough showing to weld a nut on there.

 

I had that same broken bolt for 5+ years, it only leaked when cold. Someone told me that if you remove the inner fender you can get to it with a left handed drill bit, but I call bs.

I finally swapped heads and went with stainless studs and nuts, much safer IMO.

 

i had a bolt sheared of at the head when i replaced the stock mani for pacesetter LTs. lol it was just gone and i never touched it, ran it with out the bolt never had any issues or noises...

 

I'm borrowing a 110v MIG welder from a friend. I'm going to attempt welding a nut to the broken stud.

Are there any precautions I need to take before welding? Do I need to disconnect the PCM to avoid the risk of toasting it?

I assume I should ground the welder to the engine at the alternator bracket.

 

Disconnect battery pcm will be fine ive welded on mine several times just unhook battery

 

Weld a little to the end of the bolt first, so you have something to weld the nut to. Plus the extra heat will help break it loose.

 

Yep, just unhook the battery and computer.