: 5/16 course Head Bolts?



Keith Carlson
07-08-11, 01:48 PM
There is a local guy doing Northstar head gasket repair that says he drills out the head bolt holes and re-taps them for a course 5/16 bolt and guaranties the job for 1 year.
Is it possible this would really do the job and hold up? Thanks

Submariner409
07-08-11, 02:02 PM
There is a local guy doing Northstar head gasket repair that says he drills out the head bolt holes and re-taps them for a course (sic) 5/16” bolt and guaranties the job for 1 year. Is it possible this would really do the job and hold up? Thanks

Not possible: the OEM metric thread head bolt is already larger in diameter than a 5/16" SAE bolt. (Original is M11 X 1.5........11mm is almost 1/2" in diameter to start with...........

Stick with a proven head bolt hole repair system: either studs from www.northstarperformance.com (http://www.northstarperformance.com) or the large inserts from www.huhnsolutions.com.

You might ask this mechanic just how he arrived at the proper torque settings for a "5/16 coarse" SAE bolt......................
(http://www.huhnsolutions.com)

Keith Carlson
07-08-11, 04:30 PM
He must have said 9/16?

Speedygman
07-08-11, 06:21 PM
New ideas come along all the time, some work a lot don't be careful with a new idea that cost not much different than studs by Jake. His stud kit is way over 400 completed jobs with no stud failures verses your local guy doing the work?

Keith Carlson
07-08-11, 06:57 PM
Yup, I’ll be getting the studs. I assume the jig that comes with them allows you to drill straight? Is it possible to do the job without pulling the motor?

JoeTahoe
07-08-11, 07:20 PM
Jig does come with kit. You have to drop cradle or pull engine, no room for head installation with studs in block

Submariner409
07-09-11, 09:51 AM
Yup, I’ll be getting the studs. I assume the jig that comes with them allows you to drill straight? Is it possible to do the job without pulling the motor?

Keith, Find Joe Tahoe's extensive writeup, with pictures, of his engine overhaul. It's all still in here..........down a couple of threads - 99 STS project.

sassanach
07-16-11, 03:10 PM
probably 5/8ths or m16