Stripped Cam Cap Hole

[Guest]

I somehow stripped an exhaust cam cap hole (B side, inner and forward). I usually feel when something's about to strip but not this time. It screwed all the way in but failed to tighten. It backed right out. Maybe just a few threads are doomed.

Is there enough material to do a time sert or helicoil? How about just tap the hole for a 1/4 inch screw for the time being? Right now, I'd like to do something down and dirty just to get the bike rolling again and then come back to it later, like over the winter.

It seems like every time I think this bike's done...something goes wrong, breaks, whatever.

[posplayr]

A helicoil would be least intrusive but also durable.

[Tom R]

Yeah, it happens. I repaired two of mine several thousand miles ago with helicoils... I used lots of grease and rags to catch all the shavings.

[Steve]

Whatever you do, DO NOT use a 1/4" bolt.

As others have already said, a Heli-Coil might be your best bet.

.

[BadMonk]

Hey Steve.

Thanks everyone for the replies. Yeah, I know ... helicoil/timesert is the way to go. Fairly certain I have 6mm coils in my work bench. I was just thinking out loud about a quick temp fix rather than taking the head off and all that jazz. I'm within inches of rolling it down the driveway...that's why I was wondering about something other than the helicoil/timesert.

[BadMonk]

Going to give E-Z Lok threaded inserts a try. McMaster-Carr sold them a while back. Now they're on eBay and Amazon. Stainless steel, red adhesive, generally no special tool required, quick set up.

[bwringer]

If you're talking about the solid inserts, they're really large -- the external threads are M10X1.5, and I have some doubts that there's enough material in the head for that.

I do know that lots of folks have used the coil type inserts (sold as Heli-Coil and under many other names, including E-Z Lok) with good results. These go into a much smaller hole, and kits are available almost anywhere. I'd stick with those.

[BadMonk]

thanks for mentioning that, bwringer. i was looking at the same spec and started wonder if they'd work. you saved me mental fatigue (or more) with your post.

[posplayr]

nobody posted about timeserts

[Steve]

nobody posted about timeserts

Aren't timeserts some of the "solid inserts" that bwringer mentioned?
I have never installed one, but I think there was a timesert around a spark plug I removed quite some time ago.

If you're talking about the solid inserts, they're really large -- the external threads are M10X1.5, ...

.

[BadMonk]

yeah, and no mention of down/dirty 'fixes' either. you guys are no fun... (just kidding, of course)

i know a few 'tricks' like putting some strands of copper wire into the hole (sorta like toothpicks in stripped wood hole) but it looks like nobody is brave enough or dumb enough (like me) to try that.

time serts are good but expensive. and they're a coiled affair like helicoils and others. they may make solid, heavy walled inserts too...don't know about that.

appreciate the help!

[posplayr]

Hey Steve.

Thanks everyone for the replies. Yeah, I know ... helicoil/timesert is the way to go. Fairly certain I have 6mm coils in my work bench. I was just thinking out loud about a quick temp fix rather than taking the head off and all that jazz. I'm within inches of rolling it down the driveway...that's why I was wondering about something other than the helicoil/timesert.

http://www.ebay.com/itm/Helicoil-5546-6-Thread-Repair-Kit-M6-X-1in-55466/232370995899?_trkparms=aid%3D555018%26algo%3DPL.SIM%26ao%3D2%26asc%3D46087%26meid%3D2de8aeaa60bc43b38de6db87ea29557a%26pid%3D100005%26rk%3D4%26rkt%3D6%26sd%3D120839216513&_trksid=p2047675.c100005.m1851

[Steve]

http://www.ebay.com/itm/Helicoil-554....c100005.m1851

That is a decent price for a kit that included a dozen coils.

.

[posplayr]

Aren't timeserts some of the "solid inserts" that bwringer mentioned?
I have never installed one, but I think there was a timesert around a spark plug I removed quite some time ago.





.

As bwinger said they are huge.

[Carter Turk]

rather than taking the head off and all that jazz.

You're not talking about pulling the whole head off are you, just the valve cover right?

I take suran wrap and lay over the cams and top end, poke a hole thru suran on stripped cam cap and squeeze it over the hole.
Measure depth, then drill accordingly with bit supplied with heli-coil, tap with grease on tap, clean off often.
Insert helicoil on special threading rod to desired depth.
If the cap is too close to the frame to drill, a right angle drill might do the trick.
Sometimes the little tang on the end of heli-coil can keep the valve cover bolt from seating on the cover, so breaking it off and extracting can be a little fussy.
Small flat head and tiny needle nose pliers can get it out.

I made the mistake of assuming my cap bolts were 6mm and went to insert the bolt and it was 7mm. Whoops.
I ended up grinding the bolt down and used a die to put 6mm threads on it.
There's not a whole lot of material to work with on the outside of where the cap threads.