My exhaust studs are stripped. Only 2 are fine, 4 are stripped. It looked like they have been helicoiled previously. The helicoil come out wth 2 of the studs. My question is can I helicoil it again with the same thread or do I need to go for bigger helicoil like 7/16?
Strip exhaust studs in head
- Thread starter zurud
- Start date
zurud;1218429 said:
To answer your question about helicoiling it again with the same thread, the answer is YES! Just get your self the correct Helicoil set and re install a new coil. That is one of the beauties of Helicoils.
You might need to use the tap provided to clean up the threads a little but other then that just install a new helicoil.
jugodegolf;1218445 said:
*curses*
Now I've gotta see what I tapped the hole to, god I can't remember...
yup when i installed oem studs, i chased and neverseized it all, and torqued them down to about 15lbs, half what toyota recomends.
if i were to change it up, i'd go with aaron's kit though.
if i were to change it up, i'd go with aaron's kit though.
mdr40z;1218571 said:
Indicitive that the head is annealed/soft......
Keenserts are thicker than Helicoils and have locking pins that prevent them unscrewing and once installed will be stronger than the parent metal.
IJ.;1218618 said:
Really wish I would have seen a thread like this prior to installing oversized imperial helicoils (one of which may have stripped)
I think timecerts(sp) are the best choice for these issues....helicoils are nice and all but not the best.
Muzy;1218480 said:
One of the two previous owners had a helicoil put in...it came out with the bolt and decided to unravel as well. :3d_frown:
It'll get fixed/replaced in the future.
SideWinderGX;1218763 said:
Then it wasn't a helicoil!! Helicoils can't unravel cause they are hardened tool steel they will snap before then uncoil! Sounds like it was the aluminum threads themselves came out with the studs....
And when doing helicoils please for the love of god take the head to a machine shop and have them drill and tap the holes on a mill instead of doing it with a hand drill! People wonder why after helicoiling the studs still pull out and this is why!
you can use a socket extension with a small level to keep the drill strait. No way your going to talk me into removing the head to helicoil... now if its already off...
When the stock size helicoils pulled out on a few holes i unraveled the helicoil from the other 5 holes. None of them broke, they where quite pliable once you got the first lip up...
if the head is off, do what IJ says. Im not sure you could drill the lip for the insert while the head is on the car. Should be the end all solution...
When the stock size helicoils pulled out on a few holes i unraveled the helicoil from the other 5 holes. None of them broke, they where quite pliable once you got the first lip up...
if the head is off, do what IJ says. Im not sure you could drill the lip for the insert while the head is on the car. Should be the end all solution...
Oops yeah they are not tool steel...my bad...I was thinking of the coils I have here at work!
Either way a standard helicoil shouldn't unravel easily!!! They are strong as hell! I don't know what brand coils y'all are useing but the helicoil kit here becide me I need pliars to deform them...
Either way a standard helicoil shouldn't unravel easily!!! They are strong as hell! I don't know what brand coils y'all are useing but the helicoil kit here becide me I need pliars to deform them...
The heicoil that come out are easy to break. I guess after being in the head so long. I really like to stay with metric. I saw a pretty big metric exhaust stud like m12 x 1.75. SAE confuse me a lot. Can you fix annealed head. I have a head at the machine that is warped for a year now. Machine shop oven broke so that is why they can't flatten my head. If they going to put the head in the oven to flatten won't that anneal it? Is NA head the same as turbo head? There are some NA in the junkyard. Maybe NA head is better for rebuilt since they are not abused like turbo engine.
zurud;1219083 said:
yes n/a heads are the same accept the cams which can be swaped between the two....yes the oven will anneal the head but if they cool the head down properly then it will actually regain its strength....usually its cheaper to find another head...
grimreaper;1218842 said:
Keenserts install the same way regular Helicoils do so no reason why it can't be done on the car.
IJ.;1219120 said:
you right i mixed up a time-sert with a keensert. The time-sert ive seen installed had this special drill bit end that mad a lip on the hole.