Broke bolt on exhaust manifold

[ares360]

well I have really done it now. I was attempting to change the gasket on the exhaust manifolds and broke off the head of the bolt. Any suggestions on how to fix this without taking it to a shop?

[427]

I would take the manifold lose and take a pair of vise-grips and put it near the head and try and break it loose. That way you should,t break the stud off. I have a similar problem on a 390. The manifolds was cracked so I put headers on it and now sevral years later the gasket is blown and the bolts are going to break when I take it loose. Then I,ll have to take the intake and heads off so they can be taken to machine shop. Also I havent used one but they make a stud remover I,ve seen at auto parts stores. That might work if theres room. Good luck. Brian

[willowbilly3]

It's a very common problem on the top bolts. There have been lots of discussions on different methods of dealing with the problem. Keith probably has a tech article on it somewhere.
I just blow them out with the torch and use 5/16 bolts with nuts on the back.

[fordman]

like was already stated get the manifold off. then use vise grips and pb blaster. and then maybe some heat to the head and try not to heat up the stud that is sticking out. if it breaks off again then drill it out. to get a good hole through there use a center punch to get the drill started straight. if it then fails to drill out correctly you can take it to someone to drill it out. or as already stated put a nut and bolt through it.

[ares360]

like was already stated get the manifold off. then use vise grips and pb blaster. and then maybe some heat to the head and try not to heat up the stud that is sticking out. if it breaks off again then drill it out. to get a good hole through there use a center punch to get the drill started straight. if it then fails to drill out correctly you can take it to someone to drill it out. or as already stated put a nut and bolt through it.

this sounds the easiest. thanks for the input.

[Dragon]

I got an expensive fix. I bought a Milwaukee 90 degree 28V drill for my business and in preparation for a later removal I have centered drilled my top bolts making them easier to get out later, The center drill hole gives the swollen rusted bolt some where to collapse into so they will turn easier.

I have used one of those stud removers and yuck It is a cam that is mounted off center to grab the bolt. The socket drive is in the cam part so all the force is off center. It can slip and make the bolt harder to grab and it can bend the bolt if it is soft from the rusting process. I think the tool was designed for really hard studs like used on diesels.

[fordman]

what do you mean by center drill gives rust a place to go. i dont understand that. what i think you are saying is that you drill out the hole larger and put a smaller bolt in it. but that doesnt make sence.

[Dragon]

When the bolt tries to turn it is locked in place by rust that squeezes the thread gap shut. All that pressure has a place to go if you drill through the bolt. When you turn the bolt it collapses into the hole a little bit to allow a gap to form between the bolt and the hole it is screwed into. This allows you to turn the bolt easier.

The rust removers and breakers are thin enough to pass through between the rust particles and make them a little slicker so they can slide past each other the bolt drill out method has another feature. If the bolt gets stuck you can just stick a large easy out through the hole and get it to turn.

I unfortunately know more about rust and corrosion than I care to remember. Every sailor does especially us Aviation types where we have way too many dissimilar metals in contact with each other.

[stangconv]

What are the best header bolts to prevent this from happening?

[Dragon]

Most any the low profile hardened ones that the header makers use work fine.

http://store.summitracing.com/partdetai ... toview=sku These are great.

[ezernut9mm]

I got an expensive fix. I bought a Milwaukee 90 degree 28V drill for my business and in preparation for a later removal I have centered drilled my top bolts making them easier to get out later, The center drill hole gives the swollen rusted bolt some where to collapse into so they will turn easier.

I have used one of those stud removers and yuck It is a cam that is mounted off center to grab the bolt. The socket drive is in the cam part so all the force is off center. It can slip and make the bolt harder to grab and it can bend the bolt if it is soft from the rusting process. I think the tool was designed for really hard studs like used on diesels.

i bought one of those off center stud removers and was less than impressed too. i was eyeballing 90* drills, but my pocket wasn't quite deep enough. i sure wish i bought one though. i like your idea on center drilling.

[fordman]

When the bolt tries to turn it is locked in place by rust that squeezes the thread gap shut. All that pressure has a place to go if you drill through the bolt. When you turn the bolt it collapses into the hole a little bit to allow a gap to form between the bolt and the hole it is screwed into. This allows you to turn the bolt easier.

The rust removers and breakers are thin enough to pass through between the rust particles and make them a little slicker so they can slide past each other the bolt drill out method has another feature. If the bolt gets stuck you can just stick a large easy out through the hole and get it to turn.

I unfortunately know more about rust and corrosion than I care to remember. Every sailor does especially us Aviation types where we have way too many dissimilar metals in contact with each other.

ok your saying drill the bolt out in a fancy way. usually when you get through the bolt the easy out is next. have you ever bro0ken off an easy out doing this. those arent fun drilling out.

[ares360]

ok, another problem has came up! All 8 of the lower bolt have came off easy. the other 7 on top won't move without breaking. I have been spraying WD-40 on them for 2 days with no avail.

HELP!!!

[fordman]

wd40 is worthless for this kind of work. use pb blaster. or you can use a propane torch to heat the ear of the head around the bolt to help loosen it up while you try and turn it.

[ares360]

I thought about using a torch but didn't want to catch my truck on fire. I used the WD-40 because the other bolts had rust on them.