heli coil failure

[cirell]

heli coil spinning in cylinder head of xr 400 does any one know if this can be repaired ie ally weld stripped thread hole, re drill and tap? Or any other method?

[YAM28]

Keensert

[wisejangrae]

Originally Posted by cirell

heli coil spinning in cylinder head of xr 400 does any one know if this can be repaired ie ally weld stripped thread hole, re drill and tap? Or any other method?

Yes, all is not lost !!!
There is a final repair, a thread insert (I think that is the name, will check one out when back at work in the morning, and get back to you... if no one else has confirmed)
you need to pick out the heli coil insert... pick, scriber, grab with pointy nose pliers etc and yank out

sus out the thread insert with your local nut & bolt / bearing supply outlet

just need to make sure you have enough purchase / material in the Head to allow insert to fit

cheers
Graeme

[Tomack]

Tho the heat migh be an issue, Red locktight maybe???

[Sand Goanna]

What size?
What does it hold?
How much would you spend to repair it?

[mackley]

I've used these in the past with great success, more substantial than a helicoil due to being a solid insert
http://www.timesert.com/

[Reefdog]

Where do you get in Oz?????

[Fogo72]

Originally Posted by cirell

heli coil spinning in cylinder head of xr 400 does any one know if this can be repaired ie ally weld stripped thread hole, re drill and tap? Or any other method?

Call into your local Caterpillar earthmoving dealer, ie, Hastings Deering,, and buy a CAT thread incert. All helicoils should be loctited in with 277 studlock, but if the thead has been pulled out or stripped the holes cactus, so there is no other way but to go bigger. The only thing, is it a main head bolt?, If so the barrel is got to come off so the incert can be put into the case.
Cheers Fogo..

[cirell]

Thanks for replys, the thread is damaged and its to narrow to fit a bigger size stud . I did Loctite another helicoil insert in but it wasn't the stud lock stuff. Is welding up the hole and re drill possible?

[Fogo72]

Originally Posted by cirell

Thanks for replys, the thread is damaged and its to narrow to fit a bigger size stud . I did Loctite another helicoil insert in but it wasn't the stud lock stuff. Is welding up the hole and re drill possible?

What hole is it? bike cases dont weld up real well, to much magnezium in the alloy to strengthen it.

[Precis]

JB Weld (or similar)? Pack, cure, drill and tap.

[FLICKIT]

Originally Posted by mackley

I've used these in the past with great success, more substantial than a helicoil due to being a solid insert
http://www.timesert.com/

I used a Timesert to fix a valve cover thread on my Dominator, much better than Heli-Coils IMO...

They make ones that fit the same thread that Heli-Coils use so it's fairly easy to replace screwed-up coils... They also make thicker ones which would be handy if the heli-coil thread is totally stuffed..

I got mine from the US on Ebay..

A bit of dribble I wrote about them in another thread:

Originally Posted by FLICKIT

A previous owner did a very rough heli-coil job on my head... The thread for the heli-coil was very rough and a bit over-sized so the helicoil came out on the bolt when I disassembled it... (The heli-coil was glued to the bolt with excess Hondabond also)

I ended up buying some M6 X 1.00 X 12.0mm >> Time-Sert Carbon Steel Inserts
http://www.timesert.com/

Ebay listing
http://www.ebay.com.au/itm/300692096759

They go into the same size thread as the M6 heli-coils... They should be inserted with the proper tools, the internal M6 thread tapers in at the bottom, when you install them and run the proper tool into them they expand at the bottom to lock them in....


Being cheap I didn't buy the insertion tools... I just put it on the end of a 6mm bolt with a lock nut so the bolt was only 1/2 way through it, and threaded it into the head with some Loctite super stud-lock on it, then I removed the bolt I used to install it and ran a 6mm bottoming tap through it which seemed to expand the bottom to lock it into the head fine... (hope that makes sense)

I stripped the engine down for a rebuild a few thousand miles later and the Time-Sert insert stayed in the head, and gave me no issues...

The kit with the proper tools looks like:

http://www.ebay.com.au/itm/300874927186
(bit pricey)