I recently purchased a 1997 Ford Class A with a 460 engine. The exhaust manifold issues have been well documented and so I decided to put Banks headers and exhaust on it. All my manifold bolts seemed intact and so I started. The first one came out fairly easy but the infamous rear passenger bolt broke off. Only the head of the bolt broke so it is now flush with the manifold. Reading the horror stories of seized bolts and extraction nightmares and an upcoming trip in 3 weeks, I am thinking of just replacing my exhaust system but not the manifold at this point (which should lower the manifold temps). Since the bolt is flush and accessible I am wondering if it is possible to just weld a washer and nut on there and take it on my 3,000 mile trip. I have not had any leaks and the manifold looks good. I have attached a photo and would like to get some input on whether this is doable. Another option I thought of was to just weld the hole shut since I will be replacing the manifold with headers after I get back from my trip anyway.Any thoughts would be greatly appreciated! Thanks!

IF you are a good welder you can weld a nut to the stut sticking out. Put some penetrating oil and let it set for a couple of days. You should be able to unscrew it right out.

There used to be mobile bolt extraction services. They would come to you to take out the bolt.From the photo it looks like ther may be room to get an angled drill in there to drill into the bolt so an extraction bit can be used.I've removed broken bolts in the past by using Marvel Mystery Oil (get at most auto parts stores). Heat up the engine and then squirt the oil around the bolt let it sit while the engine cools down. Then drill into the bolt insert the extractor and crefully remove the bolt. If it won't budge try more oil and let it sit over night. It once took me 3 days to get a bolt out using this method. Another option is to drill the bolt using larger and larger bits until there's just a shell left. Then use a metal pick to break out the bolt from the threads.A 3rd option is to drill into the bolt and tap it to use a smaller grade 8 bolt and washer to replace the larger bolt.

Sooner or later the broken bolt will have to be removed. I would center punch it and just use progressively larger drill bits until I got it to the point where I could tap the hole with the correct threads. Might as well fix it right now instead of going to a bunch of trouble with welding, etc to make a bandaid.

Drive it to a reputable shop and allow them to use the proper tool for a broken bolt removal. There is a stud removal tool that will grip the stud from the outside and prevent having to drill it.Soak it often and long with Blaster penetrating oil.The Banks intake and exhaust kit is a great upgrade for the 460 engine.

being a confirmed do it your selfer, driving it to a shop for the minor task of freeing a rusty bolt is simply not an option.If you want to make that trip coming up, the best bet for now will be to put the other bolts back in and leave it. If it didn't leak before it probably won't leak now.When the time comes, you need to get that manifold out of the way so you have room to work that bolt.And then you just get to it. Use all the usual. soak in PB blaster, repeatedly. weld a nut on the end and try to work it off.Using an impact wrench, low torque, low air pressure, to rattle it in and out may help break it loose.And of course heat. Nice thing is, usually in a motorhome, there is lots of room. Take off the tire on that side, you can sit under there and work it for weeks.

Exhaust manifold bolt ... advice needed! | Good Sam Community

indyzmike
Explorer
Jul 07, 2014
"Reply to update" That might work if the shank of the bolt is the right diameter and is soft enough steel to thread. If it is hard or too small, it won't work. If the bolt is soft but too small in diameter, you can find a smaller size, SAE or metric, that will result in full threads. I would still try heat to get the stud out. A propane torch is not hot enough. If you do heat the stud, don't try to turn it when it is real hot. The heat weakens the steel and you will break it off. Heat it hot, and let it cool for a while. Then you can put some force on it.
Yankee_Clipper
Explorer
Jul 07, 2014
I found that an easy-out grabbed the stud and backed it out with a 3/8-drive socket. BTW - you cannot re-use the head bolts, and they are expensive as sin. Good luck! Be careful of your back-out torque, as the head is famous for cracking.
My experience changing the head is still archived here, I think.
johnmark
Explorer
Jul 07, 2014
Update: The 8 bolts on the driver's side all came out clean. After almost 2 weeks of spraying 2-3 times a day (ATF/Acetone and PB Blaster) and hammering on the bolt that is stuck, it still won't come out. I am wondering if I should just leave it in and thread the stud and use it to secure the header with a washer and nut? Anyone ever done this? I think the Banks header flange is only 5/8" and I got plenty of stud left to get a washer and nut on it. Any thoughts would be appreciated. Thanks!
RayChez
Explorer
Jul 02, 2014
hooligan wrote:
With enough bolt to grab, (welded nut or vicegrips) apply firm pressure and repeatedly hit the bolt straight on the end with a hammer. The shock helps break the threads loose. You may have to work back and forth before it comes out. (^^^^ Raychez)
FWIW I chased all the threads with a tap before putting new bolts/studs in...

That is the way to extract broken studs or cap screws. Good info and like you posted it does not hurt to run a tap down and clean out any foreign objects on the threads.
hooligan
Explorer
Jul 02, 2014
With enough bolt to grab, (welded nut or vicegrips) apply firm pressure and repeatedly hit the bolt straight on the end with a hammer. The shock helps break the threads loose. You may have to work back and forth before it comes out. (^^^^ Raychez)
FWIW I chased all the threads with a tap before putting new bolts/studs in...
RayChez
Explorer
Jul 02, 2014
Do not apply too much heat on the head to where it will melt anything. Why don't you try using the penetrating oil first and try to work it lose. If that does not work I would weld a nut to the stud and with a wrench work it back and forth. I am sure it will come out, but this thing of applying direct heat to the head, you got to know what you are doing. Too much heat can be damaging.
Geocritter
Explorer
Jul 02, 2014
Also if you heat the stud you'll expand it, you want to expand the head around the stud. The head is a huge heat sink so you'll want to use an oxyacetylene torch to generate enough heat. Don't worry about flaming the residual ATF and PB blaster, what little is left that hasn't evaporated will promptly burn off. Still it's always good to have a fire extinguisher handy in case you catch something else on fire.

BTW if you don't have an oxyacetylene torch, Bernzomatic makes a relatively inexpensive hobbyist's torch that uses oxygen/Mapp gas that'll give you enough heat.

Steve
cwit
Explorer
Jul 02, 2014
You should heat the head not the stud. If you heat the stud it may become to soft to turn out.
Fleetwood99
Explorer
Jul 02, 2014
Great topic and thanks for your time to update the quest.

DJ
johnmark
Explorer
Jul 02, 2014
Quick update: Thankfully the remaining seven bolts on the passenger side all came out clean. Used ATF/Acetone mix and also PB blaster. Couldn't find the AeroKroil locally. Thanks for all the tips!

I am thinking about heating the stud that broke off with a torch and then try to get it out with a pair of vise grip. Should I be concerned using the torch with so much ATF and PB blaster used? All I am trying to do is heat the stud. Wondering how flammable that stuff is?

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Exhaust manifold bolt ... advice needed!

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