Good reason to change headgasket before it blows

[Kernal]

pinhead: what type of rod (alloy) would be used to braze a steel/iron block? IDK

 

[1973Guppie]

The old school way of repairing minor block deck defects without milling is to braze over the defect and then draw file it flat. Fast, cheap and permanent.

will a machine shop do this type of thing for you if needed?

 

[Pin_Head]

pinhead: what type of rod (alloy) would be used to braze a steel/iron block? IDK

It is just bare bronze brazing rod with borax flux. You shine up the block with a wire brush, clean it with hydrochloric acid, heat it with an OA torch until the bronze flows. It melts at about 1500F. Silver solder would also probably work fine and it melts at about 900F.

will a machine shop do this type of thing for you if needed?

I'm sure that they would do anything you are willing to pay for, but if you bring it in to the machine shop, why not just mill the deck? Brazing is just the quick way to repair them in the truck.

The other thing I have seen on a Dodge WC56 flat head 6 was a piece of copper wire that was pounded flat between 2 cylinders where there was flame erosionof the block because of a blown head gasket. I have no idea how long it was there, but it was holding when the head came off.

 

[Kernal]

Good info.