Exhaust head stud is stripped

[Staucher]

So I bought this bike about 2 months ago .. noticed a small leak where the exhaust manifold and expansion chamber meet the head mounting studs.. seems to progressively get worse as I ride as I notice more smoke. so I pulled off my pro circuit pipe and my exhaust manifold and I noticed the top stud is super stripped (the nut just keeps spinning on the stud). I am wondering how I can get this stud out because it seems to just be a stripped stud and it will not just turn out with vice grips.. and are there any recomended studs or sealers I can use ?  Also how am I going to screw in the new stud without damaging the threads ? As you can see I don't have enough room to put 2 nuts on and screw it out as I tried that ! 

[David C]

Try a pipe wrench first, looks like your not going to hurt it even worse.
Next your only option is to weld a nut on the end and unscrew.

[johnnyboy]

Weld a nut on the stud and it will come straight out.

I think there maybe a crack in the casting just above the stub if my eyes are functioning correctly so more work may be called for.

[William1]

The current stud is set too deep, yes, it looks like a crack is starting. New stud should be double nutted, have red loctite applied and screwed in snug (not cranked down, torqued correctly).

A tool like this removes studs best:

https://www.grainger.com/product/36T851&AL!2966!3!166594882706!!!g!71849891719!?gclid=CLHnpIWIkdUCFY1LDQod9pkJHQ&cm_mmc=PPC:+Google+PLA?campaignid=719691813&s_kwcid=AL!2966!3!166594882706!!!!71849891719!&ef_id=WPzEwAAABXqLcfAq:20170717193534:s

Also at amazon:

https://www.amazon.com/Stanley-Proto-Facom-FA-287B-6-Extractor/dp/B002FCJCVE

[Staucher]

Ok thanks guys.. first dirtbike I've really been getting dirty with I really want to know it inside and out and also see what previous owner has done... since the stud is bad I'm going to try a small pipe wrench.. if all else fails it's a good thing I'm a welder lol I'll just weld a nut on ... also didn't even notice that crack wow ! Looks like more inspecting will be done when I get home tomorrow from work. Will stay posted ! Btw thanks for the suggestions 

[Back40Moto]

I highly agree with what has been mentioned already. Using a pipe wrench may cause more damage, but welding a bolt on that stud right quick will be the easiest way out without doing more damage. 

 

 

[Staucher]

Ok well bad news is pipe wrench does not fit where I can even get a decent turn .. also was going to slot it but I can't find my Dremel.. so looks like she's coming into work with me going to weld on a nut ! But that definitely is a crack in the casting ..:( wondering if she's scrap or salvageable ?

[BOAB]

I use a puller that looks like this:

[William1]

18 hours ago, cjjeepercreeper said:

I use a puller that looks like this:

Those work pretty good, the only downside is the rotational force is not centered on the stud. A stuck stud and a crack like the OP has and that tool might make matters worse. They work great for regular, undamaged stud removal. The only issue with the tool I referenced is it has a narrow operating range so to cover most sizes you need a set and that gets pricey.

 

[Staucher]

Well I went old school and welded nuts on two of them and they came right out ! Third one I actually got with vice grips. Now I'm just wondering what to do with this small crack I found in the casting ?? 

[johnnyboy]

If it were my bike I would leave the crack alone, I would run a bottoming tap in that hole to make sure its al clean and tapped to the bottom and make a new stud that will most likely be a 3 - 4 mm longer than what came out to ease the load on that area and I very much doubt if it will ever grow or cause any problems , 

Im sure plenty will say get it welded but I have seen way way worse in my time that have never caused any problems.

[Staucher]

@johnnyboy okay definitely will run a tap through all three holes and Im going to weld it .. might aswel since I'm a welder and I can bring it into my work! Just gotta figure out exactly what metal it is .. research time 

[Staucher]

Okay new studs came in with new nuts .. anybody know torque specs ? 

[wielywilly-g]

I would just use the same torque as the nuts are spec'd.

87 in/lbs on mine.

Edited August 1, 2017 by wielywilly-g

[Bachnok]

Pretty much any aluminum filler should work.  You could probably just go across it with a tig without any filler and call it good.

in my experience most aluminum castings are a high magnesium alloy but really  I don't think it matters all that much.

btw, I know this is too late but welding a nut on is the best approach.  some of the heat from the welding will seep into the case and make the stud come out easier.