HEAD STUD THREAD

snoopy · Post by **snoopy** » Thu Aug 16, 2007 12:57 pm

Hi one of the head studs has pulled through it.s thread in the block. i want to use a helicoil it looks like it's a 7/16 -14 unc would any one know if this is correct before i order one. Thanks

Post by **wesk** » Thu Aug 16, 2007 1:49 pm

Yes, it's in your 1955 ORD 9 parts manual on page 27.

snoopy · Post by **snoopy** » Thu Aug 16, 2007 4:01 pm

thanks Wesk.

Post by **wesk** » Thu Aug 16, 2007 6:19 pm

A word of caution on heli coiling stud in the block. Be sure to seal the helicoil when you thread it into the block with Permatex #1 and then seal the stud when you thread it into the block with Permatex #1. This is very important.

Also watch which torque specs you use. The head bolts with 7/16 - 14 UNC threads get a higher torque value (65 to 75 FtLbs) than the 7/16 - 20 UNF head nuts (60 to 65 FtLbs). Install all external fittings like the lift ring and oil filter brackets then all nuts and hand tighten them. Torque to 30 Ft Lbs starting in the center and working your way out alternately to the ends. Then do the final torque the same way. Your head gasket manufacturer will specify weather or not you need to re-torque after the initial run-up.

snoopy · Post by **snoopy** » Fri Aug 17, 2007 5:10 am

Thanks again

bubagun · Post by **bubagun** » Sat Aug 25, 2007 8:49 am

I recently, had to helicoil six or eight of the threaded stud holes for my head studs, on my M38.(they seemed loose and two had the threads nearly "pulled out") I placed the head,(cleaned up and ready to re-install) back.... onto the top of the block and then used the stud holes in it, as a "guide" (perpendicular to the head/ block surface) as a drilling guide.(the 25/32" drill fit perfectly through the head.)

Normally I would have placed the block, upright, on my Bridgeport Mill for THIS operation but the engine..... just..... had a leaking headgasket...and I could not see pulling it and stripping it down for such a "small and minor" repair.

I am not worried about the small amount of shavings etc from the drilling and the tapping because I placed a small magnet into the well ,under the thermostat,inside the head. IT will trap any "chunks" or small "transients" that happen, to not simply, go to the lowest spot in the water jacket.