stripped head stud

[lambofgod121980]

Ok so my bike was running great and then shut it down went in for a snack and then when I went to fire it back up it won't start. Found out i have no spark so I got new plug and wire on the way and that's problem #1.

Second issue I had was I could feel puffs of air on my leg as I tried to pedal start it so I went to take the head off thinking I blew the gasket and discovered that I have a stripped out head stud. The stud itself is beautifull so I'm thinking that the case is what's stripped out. How do I fix this w/o getting new case or can this be "fixed".
Thanks

 

[Ibedayank]

http://www.timesert.com/html/mtrcsert.html

 

[Drewd]

I second the time sert. One thing I do on all of my timeserts is I put a little jb weld after I cut the thread and then thread in the timesert insert. It ensures it'll never come out if you are unscrewing a stud.

 

[Ibedayank]

GREEN loctite... never use it on things you want to take apart... made to hold cylinder relinings in place

 

[POPS]

Or just JB weld.
Way easier.

POP's

 

[bigbutterbean]

Whenever I get a new engine, I take the head off and make sure each headstud is turned all the way in. I do this by taking a pair of pliers and seeing if any of the studs will turn righty. maybe your head stud isnt stripped, maybe its just not turned in all the way. remember, when you put the head back on, tighten the head. bolts in an x pattern, tightening each a little at a time and repeating the x pattern until all the bolts are tight. even if you have a torque wrench, its still a good idea to do it that way.

 

[lambofgod121980]

Thanks - if there's one thing I like its options. Gonna be a few days before I can play with it. I am 100 percent sure its stripped, got kind of tight and then super loose and just keeps turning forever never getting tight. -ill probably go with loctite and jb weld first to see if that works as of my access to tools is a little limited and if that doesn't work maybe I can find a shop that can drill it out and re tap it

 

[2door]

Whenever I get a new engine, I take the head off and make sure each headstud is turned all the way in. I do this by taking a pair of pliers and seeing if any of the studs will turn righty. maybe your head stud isnt stripped, maybe its just not turned in all the way. remember, when you put the head back on, tighten the head. bolts in an x pattern, tightening each a little at a time and repeating the x pattern until all the bolts are tight. even if you have a torque wrench, its still a good idea to do it that way.

This is a good idea but instead of pliers I like to double nut the studs and use a torque wrench to make sure the studs are tight in the case. Here's where you might find an inconsistancy in stud length also which can cause problems if you use the chrome acorn nuts that came on the engine. Yes, they're pretty but many of us replace them with shouldered hex nuts. That way stud length doesn't affect how well the nut will tighten against the cylinder head.
A torque wrench is a tool that everyone should own. They aren't that expensive and can actually save you money and frustration if you happen to be heavy handed when it comes to tightening fasteners. Which many seem to be with these little engines.

Tom

 

[lambofgod121980]

This is a good idea but instead of pliers I like to double nut the studs and use a torque wrench to make sure the studs are tight in the case. Here's where you might find an inconsistancy in stud length also which can cause problems if you use the chrome acorn nuts that came on the engine. Yes, they're pretty but many of us replace them with shouldered hex nuts. That way stud length doesn't affect how well the nut will tighten against the cylinder head.
A torque wrench is a tool that everyone should own. They aren't that expensive and can actually save you money and frustration if you happen to be heavy handed when it comes to tightening fasteners. Which many seem to be with these little engines.

Tom

- this is what happened - when I got motor I used red loctite on head and studs, and I am useing the shouldered hex nuts. I use the acorns too but ontop of the nuts after they are tight and loctited. When I was taking it apart the nut on the top was siezed and the stud broke loose. I got the nut off while stud was out and used two of the nuts from the head locked together on the stud to tighten it back into the case and when it bottomed out I stoped and broke the 2 nuts loose and off they came. While putting the head back on I tightened in x pattern till seemed tight went to see if problem was fixed and still felt puff of air so I tightened it down a bit more and that's when it completely broke loose and will now never get tight.
I pulled the stud back out and its not damaged on the threads whatso ever -conclusion - I stripped the case

 

[2door]

Which is exactly why many of us do not recommend the use of Loctite and stress the use of a torque wrench.

Head bolts/studs = 120 to 140 inch pounds. In reality, that isn't much and you can easily overtighten them with the results you have.

If you used red Loctite on the cylinder head nuts, then went back and tried to tighten them the torque you applied was to the sud, not the nut. The nut couldn't turn because of the thread locking compound but the stud did and stripped the case threads.
There is no need for thread locking products on any engine fastener. Doing so is a myth that I wish we could dispel here.

Tom

 

[bigbutterbean]

This is a good idea but instead of pliers I like to double nut the studs and use a torque wrench to make sure the studs are tight in the case. Here's where you might find an inconsistancy in stud length also which can cause problems if you use the chrome acorn nuts that came on the engine. Yes, they're pretty but many of us replace them with shouldered hex nuts. That way stud length doesn't affect how well the nut will tighten against the cylinder head.
A torque wrench is a tool that everyone should own. They aren't that expensive and can actually save you money and frustration if you happen to be heavy handed when it comes to tightening fasteners. Which many seem to be with these little engines.

Tom

I do own a torque wrench, but I guess I learned to be careful and developed a feel for how to tighten the head bolts. The few times I did use a torque wrench, it was really tight trying to get between the engine and the frame. As for acorn nuts, I use a pair of dikes or lineman's pliers to cut the "acorn" part off and that has worked fine for me. I checked my head bolts every week or two during break-in, but after that I didn't really need to very much anymore. probably checked the head bolts on my current engine maybe 3 or 4 times in the last year. still, if you do have room in your frame, it is better to use a torque wrench.

 

[lambofgod121980]

Which is exactly why many of us do not recommend the use of Loctite and stress the use of a torque wrench.

Head bolts/studs = 120 to 140 inch pounds. In reality, that isn't much and you can easily overtighten them with the results you have.

If you used red Loctite on the cylinder head nuts, then went back and tried to tighten them the torque you applied was to the sud, not the nut. The nut couldn't turn because of the thread locking compound but the stud did and stripped the case threads.
There is no need for thread locking products on any engine fastener. Doing so is a myth that I wish we could dispel here.

Tom

Yeah because I totally got the idea for the loctite from this forum in my quest to make my 2 stroke as bullet proof as possible... Live and learn
I got my fingers crossed that jb weld will hold. If not nothing really lost still have to drill and retap and heli coil.

 

[lambofgod121980]

Any tips on the jb weld method to maybe improve my odds?
Crosses my fingers

 

[lambofgod121980]

Thought of something else- when I removed the head gasket it had carbon build up from cylinder to outside edge. Its in same spot when you flip it over. Was I correct about the headgasket? I have a couple and am changing it out just as precaution. And could this mean I have warped the head? Yikes

Bonus - I got the bike to spark with old parts. I cut bout half inch off both ends of plug wire and rethreaded it back on to cdi and boot. Cleaned the plug ( was black btw) and regapped the old stock crap plug kit comes with and hand peddaled the bike till it started sparkin it a$$ off. I still have new champion plug and wire comming by mail and will swap them out.

Now all I'm only worried about jb welding stud again. Have off set intake on the way aswell b/c I bought new rt carb from duane bout two weeks ago, and it has just been sitting on the bar waiting. I hope I get it fixed soon so I can try out the new carb when the intake gets here.....

 

[lambofgod121980]

Ok so jb weld prolly isn't gonna do it and imma need to rethread the hole.
Noticing kits can be pricy and a new bottom end isn't really that expensive. Can anyone recommend a time sert or heli coil kit that will do what I need and not cost an arm n a leg thanks

Got new intake today and got it and carb mounted - looks killer now just head issue....

 

[2door]

You can check the gasket sealing surface of the cylinder head. Use a known flat surface, glass works best, and a sheet of sandpaper. 280 grit will be okay to start.
Lay the paper on the glass, sand side up and lay the cylinder head down on it and begin running it over the sandpaper in a circular motion ( wax on, wax off) After just a few circles inspect the gasket surface of the head and you'll easily see any high or low spots.
Keep working until you have a uniform flat surface.
I've done this with dry paper and using wet paper. I work up to about 400 grit paper.
The trick is to rotate the head in your hand so you don't sand an angle into it. It must be flat and flush.
If the cylinder is off the case you can do the same to the gasket surface where the cylinder head and gasket goes to assure you have both surfaces lapped and ready for a new gasket and reassembly.
Good luck

PS: Most folks here know what I think about JB Weld so I won't repeat my opinions, but, the best place I've ever found for it is in my trash can.

Tom

 

[lambofgod121980]

Thanks tom - you are full of great advice and I haven't had much sucess with the jb weld method on any project - was hoping it might save me the trip to a shop but like always I shouldn't have taken short cuts and just done it right the first time
You rawk man \m/ >.< \m/

 

[lambofgod121980]

Well I finally killed engine #2 hahahahahaha I've broken just about everything except internals and in my quest to jb weld the head stud, I have managed to jbweld the jug to the case. Then I broke off the intake studs trying to close a gap on one side. Learning curve for these things sure is steep. Oh well - looks like ill be ordering new engine on payday
Brings total cash I have in the bike to bout 600 bucks - and its not even a super nice bike hahahahahaha. I am loving every second tho, and will continue to spend cuz its super fun and I enjoy working on (and riding too) my bike. But for now my bike is DOA
I'm sure ill be seeking more advice in the future and am glad this forum exists. You guys are great \m/ >.< \m/
-death metal mike from splendora TX