I'd like to cleanup the headbolt threads in my block. The block is pretty old (87) and a couple of the head bolts were pretty crusty coming out.

The size is M11 x 1.25.

This is not a hard size to find for a standard length tap. Unfortunately, a standard length tap is way too short.

To those who have done this...where did you get an extension tap of that size?

The threads are not stripped. I just want to have a nice clean bite for my new ARP studs.

Thanks,
Sonny

 

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Sonny

 

I bought a tap when I built my block and ran into the same problem, tap was too short. I tried to use it and it kept getting caught up and I was unable to control it going into the threads on my B18C1. So I just sprayed brake cleaner in the threads and air hosed it out, ran my Arps in and out of them and made sure it was smooth.....no problems. You would almost have to have an extension welded on to the tap.......not sure what else to tell ya.

 

I take an old 1/4 drive socket and jam it over the end of the tap. Use only one long extension. Kind of frightening threading the tap in and losing sight and control.