This is my first post to usmb but i just purchased a 1983 subaru gl for 140 dollars. the guy i bought it from broke a bolt that screws into the head. Im looking for a new head. or and tips on how i should drill a broken bolt out of a aluminum head. I would really like to drive this gl someday.

That's a nice find! Good luck with the project.

Where in the head? Got a photo? I've been able to drill out broken studs/bolts etc., by using a left cutting drill bit. Cuts/drills counterclockwise, left twist. Standard drills are right cutting. You can get left cutting bits at machine shops or good auto parts stores. Usually you have to get a couple of sizes, start small and work your way up, and you have to do it carefully, as straight as you possibly can. Sometimes the thing your are drilling will heat up, catch on the bit, and back itself out. Good to soak with some penetrating oil.

 

I also have good used heads...good luck.

Depending on the Area / Bolt, this ideas might be Helpful:

 

~► http://www.ultimatesubaru.org/forum/topic/70589-idea-to-re-thread-in-aluminium/

 

Kind Regards.

Thank you! such a quick response. yea the guy was going to scrap it! </3

but i saved it. its still at the guys house till monday. i was going to get it today but my dads memorial got in the way. im currently getting more details about the bolt. ive seen it. its about 3 inches long and about 2 inches arnt threaded. and the last inch is. thats were its broke into the head. the top of the bolt is facing the up skywards. if thats any help i will be able to post pics and the whole nine yards when the subs in my driveway. and how much is a good used head usmb regular?

Intake manifold BOLT snapped when replacing

very common, i've done a few.

 

1.  if there's any bolt shank left - weld a nut to the top of it.  let it cool down then tigthen/loosen it gradually many many times.  keep working it to break the corrossion.  the heat cycling from welding/cooling is helpful as is the back and forth slow progression.

 

2.  if that doesn't work/can't do it - drill the bolt out.  get decent quality drill bits, keep them cool so they last longer.  have some oil/spray for them.

*you may need to flatten the surface with a file/grinder to get a smooth area to start drilling on

*start with a really small drill bit first - go light on pressure as those bits snap easily.

 

3.  small drill bit and increase the size.

 

4.  even if you go nuts and hog it all up - you can always repair the threads later, either tap it one size up standard sized or helicoil it.  they're easily repairable - beats getting another head. those intake manifolds are relatively benign - just need a bolt going through that hole and tightening into the head.  not super critical parts/loads/conditions/moving.

that is a beautiful wagon!

THANK YOU! 

often find it is not the threaded part seized that cause bolt to break - more the unthreaded shank corroded in the manifold shaft, head breaks off and left with decent shaft to grab. There are a few different stud removing tools worth trying. Google stud removing tools and if you see one looks like a big chrome cylindrical lump, a knurled wheel mounted within and a 1/2" socket drive - that's what you will want.You may save the thread

When you do get to putting this back together, use some anti-sieze compound on the threads. I use anti-sieze everywhere, exhaust, intake, heat related, water(thermostat housing) etc...

if there is anything sticking out smack it with a hammer a few times should losen it and come right out with vice grips

well im looking at it now because its in my drive way. But It looks like i need to take of intake to get to it?

I do not want to take off the intake to get it off if i dont have too. i dont see anyother way though