Stuck #2 header bolt

[67SniperHockey]

I know this is down the road, but I'd consider switching to 3/8-inch header bolts when you get that header off (if you haven't already). I had similar issues with my 340 with 7/16 header bolts, and a couple of them were very tricky to loosen/tighten with a 7/16th wrench. I put on 3/8th bolts on and that extra 1/16th makes a big difference. There are multiple bolts that used to require an open end wrench that I can now use a boxed end. And even the tight fits -- like your No. 2 bolt -- are much easier to deal with. I also bought a box of 3/4 inch long bolts (along with standard 1 inch long) because the shorter bolts are much easier to work with on the tight, inside holes on cylinders 1, 2, 7 and 8.

https://www.summitracing.com/parts/mil-84542

Got the new 3/8 header bolts (which is what I would always use in my race applications back in the day) installed on the drivers side already

 

[Daves69]

At this point a long shank carbide bit with the die grinder should be able to get in there.

Lol, the "hogger"............

 

[66Satellite47]

I have a carbide with a 3+ inch shaft. Used for head porting. That would give room to work with. Not cheap, but will do the job. You need to be careful with the speed on the long shaft bits.

 

[blue69runner]

You know the word cant or won't is not in our vocab. So keep at it and you will get it. The thing is you would think some one making the headers would give us a little more room. LOL.

 

[flyingfeathers]

Guys I know that front header bolt is PIA all you have to do is once the header is or already off just take one of header bolts and cut it off about 1/2 inch or less from the face. Then take a 7/16 - 3/8 reg wrench and grind the 7/16 end to approx 1/8 or less at the far end of box end like a wedge and that is about the easy way to go.

 

[67SniperHockey]

Finally made some progress. Going to try and thread a nut on there next :/

 

[blue69runner]

We finely took and bent the header in a little so we would not have that problem any more. Use a piece of 3/8 inch flat bar and knocked the heck out of it on that spot. Then you could get a boxed end wrench on it. Don't remember which other one's where like that but did the same to them. Just a thought. It did not make us loose any power from the motor.

 

[67SniperHockey]

Got it. Now clean up surface, but new gasket in and add new header bolts with a dab of anti-seize on them - haha! Thanks everyone.

 

[khryslerkid]

Don't know if anti-seize will seal the bolt good enough to stop coolant from seeping. I like Permatex #2 on the bolt threads.

Nice job on the bolt removal. I was wondering if you had a welder. That's the way to do it

 

[moparwacko]

I've tried all manner of fixes for this over the years. Best I can offer is prudent header selection, sometimes shorter studs, better bolt/shorter nuts, and a little "clearancing" as a last resort.
Header removal is always more "interesting " than installation.
KK is correct, anti-seize may or may not seal in a water jacket.

 

[66Satellite47]

Anti seize won't seal the bolt. A SMALL dab of hi temp silicone will serve both purposes.