-
Hey Guest!
British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!**Upgrade Now**
(PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Hey - did you know if you click on the title of a thread it will take you to the first unread post since you last visited that thread?
but were afraid to ask: 
STOP!! Never post your email address in open forums. Bots can "harvest" your email! If you must share your email use a Private Message or use the 
smilie in place of the real @
Pretty Please - add it to our Events forum(s) and add to the calendar! >> 
Stripped headbolt
- Thread starter HarryL
- Start date
Share this page
D
DougF
Guest
Guest
Offline
Been there.
I pulled the head back off and was able to drill out the hole with a borrowed mag drill and then retapped the hole. I used a Helicoil but would have preferred to use a keysert. I couldn't find the proper size on short notice.
I would strongly recommend using a keysert.
I pulled the head back off and was able to drill out the hole with a borrowed mag drill and then retapped the hole. I used a Helicoil but would have preferred to use a keysert. I couldn't find the proper size on short notice.
I would strongly recommend using a keysert.
D
DougF
Guest
Guest
Offline
Are you referring to a stud holding the head?
D
DougF
Guest
Guest
Offline
Extra long drill bits measuring 9" & 12" are available, as are pipe extensions for taps. I don't know if McMaster Carr carries them, but I would check there first.
Not knowing how much metal can be removed in this area, I would use a Heli Coil which require less removal than keyserts.
Not knowing how much metal can be removed in this area, I would use a Heli Coil which require less removal than keyserts.
D
DougF
Guest
Guest
Offline
Yes, that shouldn't be a problem. There is a straight wire end to the inside of the Heli Coil that should allow you to run it to the bottom with a spade screw driver as long as it isn't boken off.
You can check, there may be a 6" length drill.
Good luck!
You can check, there may be a 6" length drill.
Good luck!
Offline
Here's my question, scary as it sounds:
Is the best and safest course of action to remove the engine and transmission from the vehicle, remove the head from the block, and take the block to a machine shop?
I can't imagine messing up the drilling, ruining the block or negatively impacting head torque, but I'm a worrier.
Is the best and safest course of action to remove the engine and transmission from the vehicle, remove the head from the block, and take the block to a machine shop?
I can't imagine messing up the drilling, ruining the block or negatively impacting head torque, but I'm a worrier.
D
DougF
Guest
Guest
Offline
The mag drill is key to getting things right. Once everything is set up, the magnetic base is locked it into place and it won't move.
If I were to take it to a shop, I'd probably trailer the car and let them do the work with the engine in place.
If I were to take it to a shop, I'd probably trailer the car and let them do the work with the engine in place.
Got_All_4
Luke Skywalker
Offline
I'm with KVH. That's the safest and best way. However many machine shops would install a Time Sert. A Time Sert is a full insert that is pressed fitted inside the hole you drilled and tap. In fact TS uses the same drill and tap sizes that a Heli-coil uses but you can torque to original specs.
The problems with Heli-Coil and Time serts or any inserts is that you are going to have to be perfectly square. If not, you'll never get the studs screwed in and you'll have bigger troubles. So something as critical as your head, leave it to the professionals.
The problems with Heli-Coil and Time serts or any inserts is that you are going to have to be perfectly square. If not, you'll never get the studs screwed in and you'll have bigger troubles. So something as critical as your head, leave it to the professionals.
I try the easy way out( first) myself.In this same fix once it was found that you can thread the stud further up the shaft with the correct die. Then after cleaning the threads in the block,running a tap as far down as possible,the stud found enough new threads to work.You can also buy some sleeve sealer which is a locktite product to glue in a steel sleeve to a block.It will help too.If then this should fail too , I would let a machine shop set keysert....
MD(mad dog)
MD(mad dog)
Ok guys,
Talked to my machine shop and we're
concerned about getting the helicoil down into the
block(about 5 1/2") and resting perfectly.
Talking about using a short head stud and fitting a
keysert. I'm wondering what effect this would have
on the head/block. This is strictly a road car so
performance is not that much improved over stock.
Thoughts on this action anyone ?
Harry
Talked to my machine shop and we're
concerned about getting the helicoil down into the
block(about 5 1/2") and resting perfectly.
Talking about using a short head stud and fitting a
keysert. I'm wondering what effect this would have
on the head/block. This is strictly a road car so
performance is not that much improved over stock.
Thoughts on this action anyone ?
Harry
TR4nut
Yoda
Offline
I'm not a mechanical engineer type, but I think you could torque the head with that fix - but my guess is what you would loose is that the block itself below the fix would not be in compression like it was with that deeper stud. I have no idea though if that is a fatal issue or not.
