Broken manifold bolts and sealing the manifold..

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Wrenching on my 2003 Durango 4.7L, and I'm replacing exhaust manifold gaskets.

The driver's side manifold came off easy with ZERO bolts breaking off. I was able to replace the gasket on that side easily. The passenger side is a different story. It's being a royal pain in the butt. I've been able to extract all but TWO bolts that have broken off flush with the engine. They're just not coming out. Not even some heat from a oxy-acy torch could get them to cooperate. My only option to removing them is to drill the entire bolt out, and I'd rather not do that.

The broken bolts are on the same port, one above the other, kinda. One is at 1 o'clock and the other is at 7 o'clock. The third port from the front of the engine.

I've been thinking about doing something I absolutely do not like to do, and that's to cut a pretty sharp corner here. People are going to sneer at my idea, because it's not a very good one, but in the words of Mr. Heemeyer, sometimes reasonable men must do unreasonable things. Or something like that.

Of course I have new gaskets and new hardware..

What if I grab some really high temp sealant and apply some to both sides of the gasket when reinstalling the manifold, and just leaving the broken bolts where they are, as it appears they're pretty happy with not moving...

Sure, all of the other studs and bolts would be in place to clamp down the manifold, except for in the one area where the two broken ones are.

Thoughts from the shadetree and pro-wrenchers, please?
 
Start out with a small drill bit and work your way up , maybe , using left handed drill bits .

If it has not come out with the drill bits + penetrating oil , consider an appropriately sized ezy-out .
 
Originally Posted by joshuawesl
Wrenching on my 2003 Durango 4.7L, and I'm replacing exhaust manifold gaskets.

The driver's side manifold came off easy with ZERO bolts breaking off. I was able to replace the gasket on that side easily. The passenger side is a different story. It's being a royal pain in the butt. I've been able to extract all but TWO bolts that have broken off flush with the engine. They're just not coming out. Not even some heat from a oxy-acy torch could get them to cooperate. My only option to removing them is to drill the entire bolt out, and I'd rather not do that.

The broken bolts are on the same port, one above the other, kinda. One is at 1 o'clock and the other is at 7 o'clock. The third port from the front of the engine.

I've been thinking about doing something I absolutely do not like to do, and that's to cut a pretty sharp corner here. People are going to sneer at my idea, because it's not a very good one, but in the words of Mr. Heemeyer, sometimes reasonable men must do unreasonable things. Or something like that.

Of course I have new gaskets and new hardware..

What if I grab some really high temp sealant and apply some to both sides of the gasket when reinstalling the manifold, and just leaving the broken bolts where they are, as it appears they're pretty happy with not moving...

Sure, all of the other studs and bolts would be in place to clamp down the manifold, except for in the one area where the two broken ones are.

Thoughts from the shadetree and pro-wrenchers, please?

It would still leak eventually, the lack of clamp force would allow the gasket to blow out. Any chance of getting one of the maniifold c-clamps on there?
 
Is there room to drill it out to a much larger size and tap threads to the larger size? If there is that is what I would do if I were doing that job.
 
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You were asking about hi temp sealant. Yes, I ran Permatex Ultra Copper and it is crutching me through on my 6.0 Chev with two busted bolts on each manifold at the ends. By the way, it does not contain copper. It only has a copper colour. I did not remove the manifold. I just ran a bead around each flange with the busted bolts.
www.permatex.com


78F79357-9883-49C3-9A0E-0985B5EF38D3.png
 
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Originally Posted by philipp10
Wonder what it would cost at this point to tow it in to a local shop and have those bolts extracted?


This ^. No sense in taking the chance in them leaking by doing it half way when you've invested this much already. At our shop we will try to weld a nut on if the stud is flush or just sticking out, but if recessed we go to drilling. We've got several sets of the Promaxx guides to help with that, which you could also buy too and diy if you want but my guess is a shop will have about the same cost in it as you buying the tool. I'd also suggest at minimum checking the manifold for true with a machinist straight edge or having them mill planed. Nothing worse than doing all the work to have one tick down the road.



https://www.promaxxtool.com/product/27
 
Originally Posted by joshuawesl
Tried that. With and without heat. Broke the EZ out off in the drilled hole.


Rule number 27 (I just made that up) , never try to remove a bolt that broke off due to corrosion with an EZ out, broke off going in yes, no problem. Not a very useful comment I grant you at this point, that horse is out of the barn but keep it in mind.

You need to make a small drilling jig, no need to buy one use your manifold as a template on 3/8 flat stock (aluminum is fine) with a drill press. once you have the holes drilled for the correct size bolts eg M6-8 drill the holes in the jig half way though only with a larger size drill, more on that later.

Get some round stock about 10-12 mm O.D. 10 for M6 or 12mm for M8 bolts and cut it into 1/4" and one 1" lengths (you may find washers you can use for the 1/4" ones. Depending on how many bolts the manifold uses for an example we will use 6, drill 5 of these through the middle with the original bolt hole size and the 1" long with a M3 or M4 hole.
The O.D. of these slugs is the size you will drill in the jig plate halfway through. Carefully grind any protruding bolt or tooling flush with a dremel, bolt the plate with the slugs using the smaller slugs and place the long one over the broken bolt by switching the location of the slugs any of the holes can be drilled through the longer one.

The small hole will act as a guide, in the hole with the broken EZ out in it you want to use a right hand drill bit, it will eventually loosen, once it is out go to left hand bits.
Use you original bolts to determine the depth of the drill bit including the slug and put a few turns of tape or drill stop at that point so it cant go past the slug.

Aluminum drills very easy and is easy to work with, for a longer lasting tool I would make the long slug out of steel but its not necessary for a one off job with a few holes.
Once the hole is drilled you can work up on size at a time without the slug, the bit with chase the hole by itself.

I am no expert but this has worked for me many times.
 
Originally Posted by ctechbob
If you have a welder, you can weld a nut onto the broken portion and back it out that way. SMA has a few videos of that procedure I think of Ford and Dodge both if memory serves.

https://www.youtube.com/watch?v=vDlk7B-PRAA

Should be 11 min in if that is actually the right video.
+1
This is hands-down the best way to get those broken bolts out. The heat and electricity flowing through the broken bolt during the welding brake the metallic bond and it will usually come right out. If you have broken an easy out in the bolt, you don't really have any other choice. Drilling them and trying to use an easy out is always a waste of time on these IMO.
 
Dorman and some other companies make repair clamps for broken GM LS manifold bolts. I can't seem to find the same thing for Dodge, but maybe something could be rigged up if you can't remove the bolts yourself. Amazon listings for the part numbers below will have photos that show how they work.

Snagglefoot, these Dorman numbers could be a permanent fix for your 6.0 Chevy:

917-142 Left Front and Right Rear

917-107 Right Front and Left Rear

917-108 Center ports
 
Originally Posted by Rhymingmechanic
Dorman and some other companies make repair clamps for broken GM LS manifold bolts. I can't seem to find the same thing for Dodge, but maybe something could be rigged up if you can't remove the bolts yourself. Amazon listings for the part numbers below will have photos that show how they work.

Snagglefoot, these Dorman numbers could be a permanent fix for your 6.0 Chevy:

917-142 Left Front and Right Rear

917-107 Right Front and Left Rear

917-108 Center ports



Excellent post! I have these on all 4 corners of my 2005 Silverado 5.3L. They work EXCELLENT and are a permanent fix to broken exhaust manifold bolts if you do not want to remove the broken portion for whatever reason. In my case, several of the bolts broke over time (this is common on some vehicles) causing an annoying 'tick' that gradually got worse. I will warn potential users that the driver side rear repair clamp (closest to the firewall) is a NIGHTMARE to install. I forgot what tricks that I had to pull off to install mine, and I don't want to think about it again!
 
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