Here's one for you - stripped valve cover bolt
Posted: Tue Feb 02, 2010 8:30 pm
Here is one for the very learned colleagues on the site.
My 11 year old and I were adjusting the valves on his '04 CRF80.
I let him put the valve cover on with the two bolts while I put the left crankcase cover back on.
I thought I had started both of the bolts for him, but apparently I didn't and he started one of the bolts at a little bit of an angle and wrenched it down too much before he asked if he was doing it correctly.
So we took the cover back off, and although the bolt threads looked fine, the threads in the head looked a little tweaked. I worked the bolt in by hand easily and then back out and did get a little bit of aluminum thread off of it. It wasn't much, so we cleaned that up and tried to put the cover back on.
While putting it on, I could feel the bolt start to strip as after tightening it began to get easier to turn. I immediately stopped tightening it before it stripped completely. **DRATS** I thought we had gotten lucky, but I guess not.
So the cover is on reasonably tight for now, but I don't know if it might vibrate loose as he rides it in the spring. Certainly, the cover won't come off again without addressing the situation.
What to do now? Can the bolt hole be tapped out or will I have to replace the head?
Should I wait until spring and see if it holds or just bite the bullet now while it's cold? I'll probably take it to someone to do the work as I think it might be more than I'm willing to attempt.
Whadda think?? Anybody...
My 11 year old and I were adjusting the valves on his '04 CRF80.
I let him put the valve cover on with the two bolts while I put the left crankcase cover back on.
I thought I had started both of the bolts for him, but apparently I didn't and he started one of the bolts at a little bit of an angle and wrenched it down too much before he asked if he was doing it correctly.
So we took the cover back off, and although the bolt threads looked fine, the threads in the head looked a little tweaked. I worked the bolt in by hand easily and then back out and did get a little bit of aluminum thread off of it. It wasn't much, so we cleaned that up and tried to put the cover back on.
While putting it on, I could feel the bolt start to strip as after tightening it began to get easier to turn. I immediately stopped tightening it before it stripped completely. **DRATS** I thought we had gotten lucky, but I guess not.
So the cover is on reasonably tight for now, but I don't know if it might vibrate loose as he rides it in the spring. Certainly, the cover won't come off again without addressing the situation.
What to do now? Can the bolt hole be tapped out or will I have to replace the head?
Should I wait until spring and see if it holds or just bite the bullet now while it's cold? I'll probably take it to someone to do the work as I think it might be more than I'm willing to attempt.
Whadda think?? Anybody...