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broken exhaust manifold bolts - swapping heads

lancerus

SM 2016
Full Member
Joined
Jun 18, 2016
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Another 2002 2500 question - on the passenger side - I have 4 broken bolts on the exhaust manifold.  On the driver's side, 1 so far.  The local shop I work with mentioned this is common ... something about hot/cold stress on the bolts.

I'm not leaking exhaust ... "yet".  But the prices quoted to drill out/fix are extremely high.  High enough that I'm considering just swapping to Raylar performance kit (new aluminum heads/camshaft).  Does anyone have any experience with them on their 2500 ?    Assuming I go the Raylar route - I'd probably shed additional weight with a set of headers, and replace the entire exhaust system (looks like only Magnaflow is available now).

Bottom line is I'm not sure which way to go with this yet, but do recognize i have a looming problem ...

Thoughts / advise from those who have been there before ?  Thanks !
 
I say go for the raylar setup.  I want to do same on the 2 8.1 I have. It's possible to get broken bolts out yourself,just time consuming.
 
Raylar have great packages but putting on the heads only will probably make the engine run worst.




I see they are back making Superchargers for trucks again.

 
I changed all my studs and gaskets last year. Wasn't that bad. Are they broke flush with the Cylinder head or flush with the manifold? Either way, with the manifolds out, plenty of room with the fender wells removed. 
 
No need to drill out broken studs.. Find another shop... They can weld nuts onto the broken studs and the studs will back right out. Since the heads are cast iron (Assuming your heads are) you can't get the weld hot enough to stick to the cast iron and will only stick to the stud. You weld to the inside of the nut so it will bond to the stud.. Has the secondary effect of heating up the bolt so it will slide right out once it cools off. This method works as long as the stud is sheared off at the head or slightly sticking up. If you are below the threads it may not work since you can start getting into the threads on the heads.

This is a trick I heard on another forum. You want to wait until the bolts cool to a much cooler temp or you can end up messing up the threads.

 
redheadedrod said:
No need to drill out broken studs.. Find another shop... They can weld nuts onto the broken studs and the studs will back right out. Since the heads are cast iron (Assuming your heads are) you can't get the weld hot enough to stick to the cast iron and will only stick to the stud. You weld to the inside of the nut so it will bond to the stud.. Has the secondary effect of heating up the bolt so it will slide right out once it cools off. This method works as long as the stud is sheared off at the head or slightly sticking up. If you are below the threads it may not work since you can start getting into the threads on the heads.

This is a trick I heard on another forum. You want to wait until the bolts cool to a much cooler temp or you can end up messing up the threads.

Good info except our trucks' heads are aluminum.
 
The heads are Aluminum? I have been told time and time again that they are cast iron. Go figure.

I know you have done some performance stuff on yours so I trust what you say.

Not sure then if that trick works with Aluminum heads or if there is a way to still do it. Aluminum dissipates heat really well so maybe it will work? Otherwise I guess I would be buying some performance heads too..

Rodney
 
This thread is talking about 2500 Av's... Which have iron heads..
 
For different reasons, broken bolts stuck in iron or aluminum heads can be removed after welding a nut to the shank.

It's possible to affect both with the manifolds left on; however, if the shank is broken off @ or below the milled surface on head, would be a little easier with the manifold removed.

Either way, we use the washer method.

Carefully center washer over shank, as a guide.

Build shank up, until it melds with washer.

Weld nut to washer, then let everything cool.

Remove broken bolt.

Not a problem on aluminum heads.  Like someone said, heat is dissipated quickly.



 

 
Man you are brave using a welder near aluminum head, this thread is in the 2500 area that have cast iron heads.

Perhaps you should continue this in the another area of the site

http://www.chevyavalanchefanclub.com/cafcna/index.php/board,148.0.html
 
MS03 2500 said:
Man you are brave using a welder near aluminum head, this thread is in the 2500 area that have cast iron heads.

Perhaps you should continue this in the another area of the site

http://www.chevyavalanchefanclub.com/cafcna/index.php/board,148.0.html

Aluminum & iron mentioned in this thread.  Offering a small bit of clarity to anyone chooses to listen, or not.  Once in a blue moon, I respond.  Not a moderator.
 
I get it. (y)

But a welder which uses electricity on a computer controlled truck may not be good, unless you remove every ground strap on the motor.

Us older folks love to share knowledge
 
Randy said:
This thread is talking about 2500 Av's... Which have iron heads..

Ah - I just saw the topic title and didn't know what section of the forum it was in.  :beating:
 
It is a common problem, at least for my AV. I lost count of how many I needed to replace. Almost all were located at the rear, both sides.
 
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