Update on head

Kevin - Illinois

Kevin - Illinois

Senior Member
Well, I was able to get all but two studs out. I was not pleased to find I also have two with heli coils in them, at least the studs came out of these.

First things first, any suggestions on how to get the last two studs out without breaking them. I've soaked them in PB Blaster for 3 days.

Second, any suggestions on what to do with the holes that have heli coils? I'm not sure I want to screw back into those...

Block and piston cleaning is going ok, and the head is at the machine shop getting magnifluxed and resurfaced.
 

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If helicoils are installed properly, they are fine. You could try some heat on the studs that are stuck. Heat them red, then let them cool before trying to turn them.
 
i have had luck this way:after heat/cooling, rap the top of the bolt with a hammer a couple of times, then use a pipe wrench as close to the block as possible. try loosen/tighten, loosen/tighten with a lot of luck and a little skill: presto!
 
cannon said:
i have had luck this way:after heat/cooling, rap the top of the bolt with a hammer a couple of times, then use a pipe wrench as close to the block as possible. try loosen/tighten, loosen/tighten with a lot of luck and a little skill: presto!
Click to expand...

I found that "KROIL" works even better than "presto" :)
 
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I'm good with using the heli coils if you think it isn't a problem. I had just heard that they don't hold up with 55 pounds of torque. I really don't much about them.

Quote from cannon...i have had luck this way:after heat/cooling, rap the top of the bolt with a hammer a couple of times, then use a pipe wrench as close to the block as possible. try loosen/tighten, loosen/tighten with a lot of luck and a little skill: presto!

Thanks for the advice on the heat. Sounds like patience is a good thing to have also...
 
If you try using heat, an old mechanics trick is to heat the stud just till it will melt wax, let the wax flow into the threads, let it cool and the stud should turn out realatively easy.
 
I have removed as many as 140 studs in one day and only broke 2. I figure that's pretty good odds. I don't heat the stud but only heat the block as much as possible. I use acetone and ATF or PB Blaster when the block cools enough to not set the fluid on fire. I also use Jim's method of a pipe wrench close to the block and have a fine feel for studs that are weak. That feel is the most important and refined over the last 40 or more years.
 
A mixture of half and half acetone and ATF is probably the best penetrant
known at this time. Wax is good but it requires heat and heat applied indiscriminately is bad.
We cut the broken stud off close to the surface and machine it out in the mill. Takes no more than 5 minutes per stud.
Heliciols properly installed will last forever unless the base metal is absolutely rotten. They will take at least twice the maximum specified torque for the screw.(don't try that though)
On blocks where the base metal is completely rotten or it has been previously tapped oversize, we bore it and put a steel plug in.
On modified engines we plug all the head stud holes.
 
Pete said:
On blocks where the base metal is completely rotten or it has been previously tapped oversize, we bore it and put a steel plug in.
On modified engines we plug all the head stud holes.
Click to expand...

Pete, when you say "bore it and put a steel plug in" are you referring to a thick-wall threaded insert, or something else?

And could you define "modified"--at what level do you plug all the holes?

Thanks.

Joe
 
JoeWay said:
Pete, when you say "bore it and put a steel plug in" are you referring to a thick-wall threaded insert, or something else?

And could you define "modified"--at what level do you plug all the holes?

Thanks.

Joe
Click to expand...

Yes, a thick wall threaded insert..Usually 3/8 pipe thread on the outside.

If I am putting an aluminum head on I plug all holes..
I use aluminum heads on all my modified flathead engines.
They are easier to modify than the iron ones.
For these applications I make studs from 4340 bar stock.
It's all these LITTLE things that save you headaches down the road.
 
Most people don't have pete's equipment to remove a broken stud and it's hard to centerpunch the rough top of the broken-off stud(stud-stub?). If you put the head back with some other studs and reduce the size of the stud hole with a piece of 1/4"pipe or tubing cut even with the surface of the head.then you can drill in with a long 1/4" bit enough to get an easy-out in.The 1/4' bit will take out enough material you might not even need the easy-out.
 
Screw up good this time.

:o:(I thought I was doing such a great job. Center punch the broken stud dead center drilled it out starting with a 1/4" drill and progress until I could see some threads.Ran a flat bottom tap down in thinking I was just chasing the thread. Everything look good until I ran a stud down the hole. the hole came out crooked and stud leans towards the outside of the block. NOW what can I do to fix it ?
 
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