[RAIV-Z]

Originally Posted by LMSRACER

Good afternoon Ed,
This is the approved method of repairing the cylinder head bolt holes in the Cadillac Northstar V8 Block and the Oldsmobile Aurora V8 Block. The engine's develop coolant consumption/cylinder head gasket failure issues due to a loss of "Cylinder Head Clamping". The threads in the block pull out and the cylinder head bolts break.

In your situation, be sure that there is adequate material in the cylinder heads for milling the surfaces true, drilling-tapping & threading for these inserts. There may be coolant passages close to the surface. If you sonic check the head surface and find that there is ample material/thickness for this repair, then, even if you were to break into coolant that wouldn't be a problem. Many cylinder heads have rocker studs that penetrate/protrude into the coolant passages. It matters most that there is ample materiall thickness for "Full" thread engagement of the threaded insert.

If you go with this product, explain to the folks at timesert what you intend to do and the available thickness of the material. Let them guide you in the correct procedure.

I've personally performed the repairs on the Northstar V8 Blocks with the approved/expensive timesert kit. It's slick and fairly simple, once the engine is out of the vehicle and disassembled that is.

One more thing to consider is that the timeserts are designed to be "Thin Walled" and therefore the size of the hole that excepts them isn't much larger than the holes that you already have. For that reason, a "Thicker Wall" insert may be of more benefit. Possibly, timesert makes such an animal....

Good Luck,
Larry S.


http://www.precisionautomotivespecialists.com

Good point about the TimeCert "Thin Walled" design, there are a few other types of thread inserts which might work.

http://fulltorque.com/fft.htm
http://www.repairengineering.com/keensert.html