Ford 400.

I am getting my heads back from the machine shop tomorrow and would like to get my truck running again after having blown a head gasket. I have all new Felpro gaskets, the block surfaces are all cleaned up and I have everything else I need to get the job done except one thing. I bought a set of ARP cylinder head bolts but I don't want to put it back together without getting the bolt holes in the block cleaned out so the heads will torque down correctly. I am going to try to track down a thread chaser in the morning but I don't know if I'll have any luck. Here are my questions:

1.) The bolts are 1/2 inch but I don't have them here with me now so I can't look at what the thread count is. If someone happens to know what thread these bolts are it might help me to track down a thread chaser first thing in the AM.

2.) if I can't find a thread chaser what's the best way to clean out the bolt holes? I hate to use a tap and brake cleaner but I might have to give that a try unless somebody knows another trick.
Any ideas are appreciated.

Thanks.

 

Don't use a tap in a hole that just needs to be cleaned. You will remove more metal than you want. Use a thread chaser or thread restorer. Wire brushes in a gun cleaning kit may work also.

 

Cut a groove down the side of the one of the old bolts, use a cut off wheel or something that will leave a clean edge like a tap has, run it in and out, blow out the hole with compressed air if you can, usually a bottle brush, brake clean and compressed air will clean the hole enough, unless there was alot of rust in the holes.
Good luck.

 

2x. thread chasers. IIRC $14 a set at Summit.

 

x3 if you end up with any burrs on the threads, that will change the torque value on that bolt by enough to have a possible blown head gasket

 

Thanks for the advice. I was able to track down the thread chaser today so I'm in good shape. Just for reference in case anybody can use the information in the future the cylinder head bolts on the 351M/400 motors are 1/2-13 as is the thread chaser.