Combines help with exhaust manifold bolts

[Hyper_Harvest_II]

kw, Keep using heat and try using the air wrench with short bursts to see if bolt will break loose,might even try going forward then backward.Once you heat the area around the bolt go to the next bolt to let the heat sink into the first.Usually this will work but not always. If you break a bolt off you can try welding a washer to bolt and then welding a nut to washer and try the air wrench again.If bolt is broke off below flush we usually center punch bolt and using a pilot bit drill a hole through center of broken bolt.Then using the correct drill size for the metric bolt in manifold drill hole to that size. Then using the correct tap just re-tap the hole this usually works 95% of the time.Rarely have to use helicoil. Good luck, Hyper Harvest II

 

[silverbill]

I would not use a easy out. Seems like they always expand the bolt and then break off. I'd try a left hand drill bit first if the bolt is broke off below the surface. May also want to try drilling a small hole and then tapping a torx bit into the hole. Torx bits don't expand the hole like an easy out. Also might try heating the bolt itself rather than the area around the bolt. This expands the bolt and then when it cools it breaks the rust holding the bolt in the head. I've used this method on broken_stuck bolts on heavy equipment and it works.

 

[redman]

I work at a red dealership and we share the same engine, and have encountered the same problem. We have had terrific luck using X-TRACT AllOY rods from X-ERGON. This rod has special flux which protects any exposed threads and once you have enough of a nub built up a nut can be welded to it with ordinary rod. The heating and cooling of the welding process helps free the bolt.

 

[wayne]

Use a punch and hammer on bolt to jar rust loose first then heat around bolt not the bolt itself if possible. Use a hand tool and loosen the bolt a little then tighten back up a little, keep doing that until it is freed up to come out. If you drill use little bit first make sure it is centered then keep stepping up sizes should get bolt thin enough to easy out or peel out. Be careful with oversizing hole that you don't get into water passageor something else. Cat has jig that bolts on 3406's so you can drill straight cummins might too, good luck

 

[brad_c]

That's the stuff i was thinking of. Brother is a truck shop foreman and introduced me to that stuff a couple of years ago - simply amazing! It makes working on an exhaust somewhat bareable. He said they haven't seen it not work. Only drawback is it is expensive - like $10 per rod. Might be more to the common man.

 

[iowaruss]

A trick that works good for me is to drill a hole in middle of bolt[pinch smaller than threads]Hold a oversize nut over the broken stud.With welder fill the hole with weld and as you get to the end of bolt weld the nut on.let cool completely[naturally].this trick has always worked good,you need small welding rod[wire welder works better].when the bolt cools it shrinks good luck,we have all been there

 

[Delray]

A mechanic freind of mine once told me to heat the bolt itself, let it cool, heat again, let it cool then use an impact wrench because they will rarely break a bolt. I've had alot of good success with this method. Good luck!

 

[kw]

In keeping with the "what worked" theme I thought I would post again now that we have the cummins fixed (well almost). First of all Cummins does not make a jig for drilling out the broken bolts, they said just drill them out and use helicoil, Cat is a little more user friendly here evidently. We started using a three pronged approach--heat, air hammer beating on the heads and impact wrench on lower setting. Using this we only broke 2 more bolts for a total of 4 out of 12. What a joke, If I couldn't come up with something better than this I would quit making engines. It amazes me that with the technology of today that everone just accepts this as what happens. (I base this acceptance on conversations with cummins and local agco dealer who both said this is just the way it is when working on exhaust manifolds.) Sorry to vent, but a couple hour job turned into a major repair. I think the tips here definitely kept us from breaking more bolts, as there were several really stubborn ones. I wish we could have gotten ahold of some of that rod 2 of the guys suggested, but not locally available as well as no correct tap to try hyperII's idea (really would have liked to keep original holes). We gave in to time constraints and drilled them out and put helicoils in as local dealer stocked just the right ones (imagine that). First time trying helicoils hope they work. Thanks to everybody for the tips. Kirk