VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 I am about to lose my mind with this engine head..

You may be able to hit that small remaining piece with a center punch(tap it easy on the side,counterclockwise)and it might come out.Good luck !

Mike,

Maybe, but remember when trying to back it out, it is best get as far away from the center of the broken bolt as you can. That is, you want to get on the outer edge. More force for turning that way. Counterclockwise is right. A chisel will allow you to do this where a center punch may not.

Charlie

If you can't get it to turn out with a chisel you may want to make a drill guide. You could make the drill guide fasten to the top of the block using adjoining head bolt holes. By doing this you could assure that you are going to drill into the center of the broken head bolt. I would also recommend using a good left hand drill bit. Use plenty of lube when drilling. More times than not the drill bit will end up loosening and turning the broken bolt out.
Good Luck
Don

Another thing you could do to protect the exposed threads in the block is to slide a thin-walled steel or copper tube down the hole and then start banging away with center punches and chisels.

Cheers, Dean

Charlie,
I did the chisel and hammer today and thankfully it all worked out. Now its time to start over. Does anyone know where I can find a new set of all these head bolts? If one broke I am thinking I might as well get all new grade 8 bolts.

Thanks for all the help guys,
-Davis

Davis,

I am glad to hear that.

On the bolts, I don't see how they would fail having only subjected to 65-70 pounds of torque. They must have been over-torqued at some point. Well, at least one.

I would eye-ball and measure the rest of them to see if any are stretched or not and then test them (see below). If they test good , then I would not fear using them. If you need only one, let us know. Someone may have a spare one from and old engine that is just used for parts. I may have one.

You may test the ability to take the torque by screwing them into the block without the head and gradually go up on the torque range until you reach 75 pounds. Concentrate when you reach above 55 pounds. If you FEEL the end of the torque wrench start to give without the bolt turning, back off and screw it back out.

The head bolts have some elasticity and should give warning of stretching if you are paying careful attention. All that torque good, measure good and pass the eye-ball test, I wouldn't be afraid to use. They should take much more torque than 75 pounds so taking only 65-70 should be a snap. Sorry about the pun!

Good luck with it. And let me know if can't find a NOS set of bolts or a partial set.

Charlie

You can measure the bolts and check with a heavy equipment dealer such as Caterpillar for grade 8 bolts. While some of your bolts may be good installing all new grade 8 bolts will eliminate the trial and error method. If you do want to test and re-use them I would put a nut in a vise and torque them to the proper torque plus at least 10 percent for good measure.

don't waste your time on old bolts . a question , are any bolts shorter than any other ? I want to eliminate the idea of you " bottoming out " a bolt , there bye twisting it off ? someone here knows the answer . frank