454 chevy stripped head bolt hole
 

any you guys have any ideas about fixing one stripped hole in the block of a head bolt? heli coil? size i need? ive got just one that is stripped out right in the middle and its a long one not the short one in the bottom after i get it fix ed im going to studd this one thanks mike in new mexico

They make tools to drill and tap your block straight but if you cant find one you can make one if you have access to a mill. take a piece of steel at least one inch thick and drill a hole in it thats the tap drill size,then drill another one next to it and tap that one.on the other end cut a slot that is wider than the 7/16 bolt.position the slot so it will reach any other head bolt. simply center the fixture up on the bad hole and bolt it down.using the tap drill size hole to square your hand drill,drill the bad hole to tap drill size. loosen the fixture and position the hole you tapped over the bad hole and clamp it down. screw the tap through the fixture and into the block.thats all there is to it.Bill

i have had better luck useing a key insert over heli coils. just my .02 worth

What is a Key Insert?

Ed

I have used Hendrens method and found it to be easy. It's pretty much imperative that the hole be perpendicular to the deck and w/o the block your hand drill will wobble enough to make the hole oversize. Ditto when you tap and then you have threads that are far from perfect. Makes it possible to strip or pull the heli-coil if not done right.

key insert is a thead insert with 4 locking pins that you drive in to lock in place. they don't come out or pull like a heli coil.

Ed,
I think this is what he is talking about. You can get them in carbon or ss. I have used them in my machine shop and they do work very well. They make a tool to set the pins once they are screwed in. I make a threaded installer that screws into the ID and has an OD that stays inside the pins, then use the tool to set the pins.

http://www.jlindustrial.com/JRI-6592...T/product.html


Curtis

that is what i'm talking about. i buy then from macmaster car. that is what they call them is key sert. best fix i have found. can't beet them on rocker bosses, etc..

I too have used these,for many years,they are a great fix for cast iron and aluminum

i guess it depends on where you live..we call them nut serts...works well

brian