Broken bolt

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Slant Six Bumblebee

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I broke the bolt that holds down my choke thermostat, I was thinking to take my exhaust manifold to a shop and have them extract the bolt. When i go to take off the exhaust manifold will other bolts break and would i be better just taking the whole car to the shop?
 
Use Hand Tools, Start with a small tightening of the bolts (less than qtr turn) and
then go back and forth as you come out. Like running a tap.
It's the rust between the manifold and the bolt that you have to break loose...
 
Welcome! sorry you have to start with a broken bolt story...IF any of the bolt is above a flat area where you can grab it with Vice-Grips, heat it up with a propane torch and melt a crayon around the bolt. It may lubricate it enough to back out. Do you have a welder or know someone who does? weld a bolt to the broken one and back it out...may help to use the torch/crayon combo again. Good luck!
 
Is the bolt broke in the hole or is some sticking above it????
 
Use Hand Tools, Start with a small tightening of the bolt (less than qtr turn) and
then go back and forth as you come out. Like running a tap.
It's the rust between the manifold and the bolt that you have to break loose...


It will also help to heat the area around the bolt with a propane torch to let the heat help loosen the bolt...
 
I broke the bolt that holds down my choke thermostat, I was thinking to take my exhaust manifold to a shop and have them extract the bolt. When i go to take off the exhaust manifold will other bolts break and would i be better just taking the whole car to the shop?
If it is just the choke thermostat and the other bolt threads are good, I would just use the single bolt to hold the choke thermostat housing in place until there was a need to remove the complete intake / exhaust manifold assembly and do the repair then.
 
If it is just the choke thermostat and the other bolt threads are good, I would just use the single bolt to hold the choke thermostat housing in place until there was a need to remove the complete intake / exhaust manifold assembly and do the repair then.
the other bolt is striped as far as i can tell :(
 
If you end up removing the manifolds, the FIRST thing to do is SOAK all the fasteners down GOOD with a premium penetrating oil and that's NOT WD40. Use something like PBlaster or Seafoam Deep Creep. Soak them DOWN. I mean DROWN them. Then come back and do it again. Then let it sit a long while before you attempt to take it apart. I did that to mine and got every single one of them out without breaking a thing.
 
Only bolts in an exhaut manifold are the choke wells. All others are nuts on studs. Take Rob's advice and drown them. If they dont loosen with a steady pull, try and tighten a bit to break bond. If there is nothing left to grab, you can drill it out and pick out the shell but you need to center punch it first so the bit wont follow the angled or convex break plane. If you got lefty drill bits, those are the best as they have a chance to unscrew while cutting them. Sometimes when the head snaps off, there is no longer tension on the broken part and it will unscrew rather easily once something can turn it, Even a thin welding rod tacked ti it. The end studs on Mopar V8 heads are famous for busting as the holes are not blind to coolant.
 
Light intermediate tapping on the broken bolt while it is soaking will help the oil down the threads. Where are you located?
 
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Kroil, PB Blaster, or Seafoam, like Rob said. Let it soak. The tighten trick works well too, as said in post#2.
 
There is an inductive heater devise that I have seen.

I also have seen an impact and water.

Youtube for illustrations
 
You probably wont have problems with the other bolts removing the intake. The choke thermostat bolt is exposed to a lot of heat so they get rusty. They are also a stainless bolt so the dis-similar metals can cause problems too.
For penetrating oil, Kroil is hands down the best. PB blaster works ok, just cant stand the smell of it. Smells like a skunks ***.
 
Find someone with a engraving tool. Like you use to put your name on tools. Put it on the center of the broken bolt. The vibrations from the tool will sometimes loosen the stuck bolt. I have good luck with this method.
 
That don't mean they work better.


No, but who's gonna spend the $$$$ on an acetylene set up just to loosen a bolt if they already have a propane torch...

Propane will get the job done and is much cheaper... Many people already have a propane torch...

Support Hank Hill....
 
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