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Removing broken cylinder head dowel pin

383 Mopar, front dowel pin passenger side, not sure how this happened but. I am working on this for a friend. Pulled the heads to have them ported and the dowel pin is broken off flush in the block. Any ideas on how to get it out?



Thanks
 

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Drill and a easy out, or the best way I have seen it done its to drill it and tap it with something small then use a slide hammer.
 

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Find a nut with the ID just big enough to match up to the dowel.
Mig or stick weld it to the broken piece. Twist out. The heat helps loosen things up. If you want to, you can spray it with some PB Blaster or Liquid Wrench before twisting it out.

Did this on a broken head bolt that broke flush with the deck in a big-block. Yeah, I know isn't the same as a guide dowel but.........
 

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I'd drill it and tap it for like a 8/32 screw then use the screw with a nut on it to pull it out. I'd heat it up too. Slide hammer might work too.
 

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If someone used a standard dowel pin you will need a carbide or M42 drill to get thru it. In the case you will not be able to tap it unless you have a carbide tap. I would go along with welding to it and try and pull it out that way.
 

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If someone used a standard dowel pin you will need a carbide or M42 drill to get thru it. In the case you will not be able to tap it unless you have a carbide tap. I would go along with welding to it and try and pull it out that way.
A good sharp HSS drill bit will drill that dowel no problem... Especially at that diameter. Tapping will not be difficult either just take your time. I have workedin a machine shop for a good many years now and you will be amazed at what you can do with HSS. we go through thousands of dollars a day in carbide tooling (10 cnc mills and lathes manyh more conventional) the reason we use carbide most of the time is so that we dont have to stop to change the drill or endmill as often with carbide. Unless it is a super hard item. These dowels are case hardened meaning they are only hard on the outside for a few thou.
 

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A good sharp HSS drill bit will drill that dowel no problem... Especially at that diameter. Tapping will not be difficult either just take your time. I have workedin a machine shop for a good many years now and you will be amazed at what you can do with HSS. we go through thousands of dollars a day in carbide tooling (10 cnc mills and lathes manyh more conventional) the reason we use carbide most of the time is so that we dont have to stop to change the drill or endmill as often with carbide. Unless it is a super hard item. These dowels are case hardened meaning they are only hard on the outside for a few thou.
I also work in a machine shop and am used to good tooling. problem is many guy shop use drill sets don't have good HSS drills (i.e. M42 or Tin coated). Dowel pins are usually 1060 with a carbed case and breaking thru the case is where the problem will occur.
 

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It is already broken through the case. It is broken off.

Like said above just keep it centered when you drill it.
 
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