beans
Dork
4/12/14 9:20 p.m.
Does anyone know a good way to extract broke exhaust manifold studs out pf an aluminum head? Threw my header on today, saw someone had previously broken one off below flush, and i broken one tightening everything down after a heat cycle. I dont believe the one i broke is below flush, but im fairly certain there isnt enough threads to get anothee nut on it. Could i possibly drill them out with a slightly smaller bit and pick the rest out of the threads? Really would rather not helicoil this crap.
Car pulls hard as hell from 4k to redline now, though.
Drilling the stud out can be done, but the trick is getting your hole started exactly in the middle. You then drill a starter hole exactly straight and then work up gradually with larger bits until you've removed everything but the threads. If the stud is above flush, file the top flat first and it will make it easier to centerpunch it.
Depending on the engine and the car, it will probably be a lot easier to do if you take the head off and put it on the workbench.
EvanB
PowerDork
4/12/14 9:34 p.m.
Left hand bits and screw extractors along with heat and a good penetrating oil.
If it's not flush or below flush, try welding a nut onto it.
beans
Dork
4/12/14 9:43 p.m.
stuart in mn wrote:
Drilling the stud out can be done, but the trick is getting your hole started exactly in the middle. You then drill a starter hole exactly straight and then work up gradually with larger bits until you've removed everything but the threads. If the stud is above flush, file the top flat first and it will make it easier to centerpunch it.
Depending on the engine and the car, it will probably be a lot easier to do if you take the head off and put it on the workbench.
Latter is too much of a pain. I'll try the former method.
t25torx
HalfDork
4/12/14 10:56 p.m.
EvanB wrote:
Left hand bits and screw extractors along with heat and a good penetrating oil.
Minus the heat, this was how I got 4 broken studs out of the aluminum head on my SAAB 9000. Mine all broke below the surface, so I took one of the broken studs, drillid it out centered on my work bench, screwed it into the broken stud hole and used it as a guide to make a centered hole in the stuck stud. Then just worked my way up to the large reverse threaded extractor.
i saw this on tv, so it has to work:
http://www.youtube.com/watch?v=WgmBu0M0rvM
patgizz
PowerDork
4/13/14 7:32 a.m.
i had 2 broken bolts in my 5.3's aluminum head. about 1/8" in the left hand drill bit caught enough to just back them out.
DrBoost
PowerDork
4/13/14 7:50 a.m.
beans wrote:
stuart in mn wrote:
Drilling the stud out can be done, but the trick is getting your hole started exactly in the middle. You then drill a starter hole exactly straight and then work up gradually with larger bits until you've removed everything but the threads. If the stud is above flush, file the top flat first and it will make it easier to centerpunch it.
Depending on the engine and the car, it will probably be a lot easier to do if you take the head off and put it on the workbench.
Latter is too much of a pain. I'll try the former method.
I've heard that from a lot of techs. Then I reminded them of that statement, dozens of hours later when they are getting the broken stud out....on the bench. It's VERY hard to drill a hole dead center, and dead straight in the perfect world. With the head in the car, it's nearly impossible.
DrBoost
PowerDork
4/13/14 7:51 a.m.
t25torx wrote:
EvanB wrote:
Left hand bits and screw extractors along with heat and a good penetrating oil.
Minus the heat, this was how I got 4 broken studs out of the aluminum head on my SAAB 9000. Mine all broke below the surface, so I took one of the broken studs, drillid it out centered on my work bench, screwed it into the broken stud hole and used it as a guide to make a centered hole in the stuck stud. Then just worked my way up to the large reverse threaded extractor.
How is it that some of the simplest ideas are so brilliant? I never thought about that.
confuZion3 wrote:
If it's not flush or below flush, try welding a nut onto it.
This. If you've got a way to do it, it's the fastest, easiest, most effective method I've ever tried.
t25torx wrote:
EvanB wrote:
Left hand bits and screw extractors along with heat and a good penetrating oil.
Minus the heat, this was how I got 4 broken studs out of the aluminum head on my SAAB 9000. Mine all broke below the surface, so I took one of the broken studs, drillid it out centered on my work bench, screwed it into the broken stud hole and used it as a guide to make a centered hole in the stuck stud. Then just worked my way up to the large reverse threaded extractor.
This.
Also this: ProMaxx
None for your application, and expensive to boot. However if you deal with this problem on these engines on a regular basis they can be worth their weight in gold.
Easy-outs!
http://www.harborfreight.com/12-piece-screw-extractor-set-40349.html
Knurled
PowerDork
4/13/14 6:45 p.m.
The ONLY easy outs to use are the straight sided ones. The twist ones are exercises in frustration.
Fortunately, exhaust studs usually break because they were brittle and sheared off in service, not from bottoming out or galled threads during installation. The threads are generally in good shape so removal is nowhere near as big of a pain in the ass as if some goober broke the bolt against tightening torque.
t25torx wrote:
Minus the heat, this was how I got 4 broken studs out of the aluminum head on my SAAB 9000. Mine all broke below the surface, so I took one of the broken studs, drillid it out centered on my work bench, screwed it into the broken stud hole and used it as a guide to make a centered hole in the stuck stud. Then just worked my way up to the large reverse threaded extractor.
You could market that and make a mint from autozone and the like
DrBoost
PowerDork
4/13/14 10:35 p.m.
Cool_Hand_Luke wrote:
Easy-outs!
http://www.harborfreight.com/12-piece-screw-extractor-set-40349.html
I can't imagine the torture I'd be in for if I used HF easy-outs. Even the thought of it makes me shiver.
I don't use easy-outs as a general rule. I find theres almost always a better alternative.
In reply to DrBoost: I've found there's almost always a better option than using harbor freight
Do the straight edge easy-outs work pretty well? I have a couple in the shop but haven't had the joys of using them yet haha