I keep breaking bolts :(

[Mike Trout]

Im slowly working on my 69 1.1 GT and well, I broke one of the exhaust manifold bolts that goes into the downpipe, went to drill it out, drilled crooked but I dont know anyone that does heilcoil work, so I got a manifold from wanabeopelowner and the downpipe is still conected how should i carefully go about extracting these? I soaked the last ones in PB Blaster and WD40, im going to use maybe a lil heat, also my hood hinge bolt broke off in the hood, thats was nice, bolts keep breaking how can i prevent this from happening more often
My poor GT is already in bad enough shape
Mike,

[GTJIM]

When you find out how to stop breaking bolts just let us all know - I have been breaking them for 40 years

There are several steps, of increasing levels of violence, to try on stubborn threads. Sprays, heat and hitting to name a few.

Tapping the bolt head with a hammer can break-up the rust around the threads and make the bolt a bit longer to release the tension under the head.

Doing the bolt up a wee bit before undoing it works sometimes.

Soaking in Coca Cola disolves some rust (phosphoric acid in the Coke does this)

PB Blaster and/or WD40 are always good standbys - and I have even used Nitirc Acid!

When al else fails drilling them out is OK - but has to be straight!

BTW: Most Honda Motorcycle shops do metric helicols or thread inserts

HTH

[jeff denton]

I know. It is frustrating. Professional mechanics always agree when I say there is just something about that metric thread that seems to be more prone to siezure. I don't know why.
The only way to prevent this could only happen when the fastener was installed long ago. I am a huge believer in anti sieze, we've discussed this before. You don't know why until you've taken apart something that was put together MY WAY previously... or you'd rather have the problems...
So, back to penetrating oils, etc. Plan ahead. Use such oils on the threads of bolts that are held in by a nut. Days in advance. Hit em with a shot several times in these days, be patient, let it do it's job. It doesn't do much good to spray them and wrench them right away. Wait.
When a bolt is into a part that you can't see the threads in, a bit of heat helps. Imagine where the bolts threads are in that casting, warm that area up a bit, imagine the female threads in the casting getting warm and expanding away from the male threads in the bolt.
Sometimes this whole thing becomes a nightmare. We could discuss where to go from the basic first step just described, but that tends to be a case by case situation. Drilling bolts out is one way but only after you have pre- planned how to fix the damage you might cause...

[73OpelMan]

I can not quite give you information on how to get threads out of the holes but I can tell you I have been there too. Haha!

I have broken so many bolts on my GT it's not even funny. Worst time was getting my Front bumper off for polishing. I broke EVERY bolt holding it on but one. Since then I have been replacing every single bolt I have taken off and I suggest doing that. It helps in the long run ecspecialy when you are "slowly restoring" the car, if you are doing that! Also another reason is everything is easier to re-install if needed!

Hope somthing helped!
Spencer

[okiejohn]

just a note from personal experiance even if it doesnt look like it will burn have a extinguisher handy for those oops it lit off chances when using a propane torch for heat

[maglinjosvinn]

i've been spraying the bolts on the rear end of my GT for a week, and it'll be 3 maybe 4 weeks more before i start pullin it apart. i pray to whatever god is available i don't start breakin bolts.

[soybean]

If and when you get the bolts out, it's just a matter of time, go to Sears and get their small metric Tap and Die set. It covers almost all of the bolts on the Gt. Before putting anything back together, run the tap through it. Any bolt, run it through the Die. Use "Antiseize" on the bolts where applicable. As Spencer said replace the ones that can be replaced with newer ones. Good luck, it's fun. Gotta love these cars. Jarrell

[GTJIM]

By the time your GT is done you will be the local 'Thread Restoration Guru' -
I just made a day's wages removing twenty studs from a set Gale Banks Turbo ali exhaust manifolds from a 454 Chevy motor in a Jet Boat - the owner is thrilled that $18,000 of irreplacable parts are no longer scrap.

[Dmcbrass]

Remember that if you do use antiseize, you need to lower your torque settings. Antiseize is such an excellent thread lubricant that you can easily over stretch a bolt before you ever reach the published torque numbers. In industry we use three different torque numbers. (dry, lubricated, and antiseize)

[Paul Martin]

Good point Dmcbrass, with regards to antiseize. Mike, all good suggestions about how to avoid breaking bolts. I will add patience to the list. As Maglin is doing, spray them down with PB blaster if you can get to them, tapping with a hammer, and be patient, it can take awhile for the oil to penetrate.

Opps, Jeff already covered the bit about patience and persistance. Sometimes if you work the bolt with gentle pressure in, and then try backing it out, see if you can feel the tension in the threads, this instead of going with the brute force turning it out. Eventually that bolt will have to come out, heat was mentioned, have used that myself with some success, especially for exhaust bolts.

If your patient and use loads of lube, sometimes you can get stubborn bolts out, if not, well then it will escalate into more effort, and either the bolt will come out or it will break off, so it sometimes has to be, sadly enough, then drill it out and retap the hole. Sharp drills and a steady hand are a must. If you can, use a sharp punch to make a starting point for the drill, use a small drill at first and work up the sizes up to approximate the original bolt size in the hole.

I am new to these forums, hope I get it right, I have had an Opel GT for the last many (30) years, and am about to do a reconstruction for my next incarnation, my last one lived fine for many years, but rust finally got it, easier to move to a new unibody with much less rust. This time I am not fooling around, I am using POR-15 and serious additions of any of the areas our GTs usually fail.

Paul

[Gary]

Just remember the old rule of thumb when tightening bolts: Tighten it to half a turn before it breaks

[hrcollinsjr]

Originally Posted by Mike Trout I got a manifold from wanabeopelowner and the downpipe is still conected how should i carefully go about extracting these? Mike,

I didn't read any of the previous posts so if someone else has already given this advice please forgive me.


If I don't care about the downpipe I cut the bolt heads off with a torch. This will leave enough sticking out to grip with Vise Grips. Soak with penetrating oil. Use the torch at a later date to heat the manifold and while it is HOT use the Vise Grips to break the bolts loose. Try going back and forth with the bolt. Sometimes moving it clockwise will break it loose.

Good Luck!

Harold