I tried to put the heat shield on my 455 powered 69. That required removing the lower front head bolt. Well it came out with the threads smushed (that's a technical term). The block thread seems to be OK. I have the correct bolt with stud for the heat shield. It's a very little bit longer than the old bolt (probably less than 1/16" longer. ) When I installed it the threads got Smushed a bit and it didn't want to go in far enough to seat on the head casting. I'm afraid to push this bolt any more to torque it. I've tried the obvious and put a screw driver into the hole. I've got at least 1/4 " of extra room before the bolt bottoms out. I think a flat washers under the bolt head should do the trick. But I'm not sure I can properly torque it with a washer there. I think I can but I'd like another opinion. Should I recut the "smushed" bolt threads before I install it? Any help is appreciated.
Yep. Run the bolt through a die and even better re-tap the hole to be safe.
2012 Mustang Boss 302 #1918, Competition Orange. FGF replacement 2006 Mustang V6 Pony, Vista Blue. Factory ordered. 2019 BMW X3 (Titled to the wife, but I'm always driving it for her. So I'm claiming it) Old projects, gone but not forgotten: 1967 FB 400, original CA car. After 22 years of work, trashed by the guy who was supposed to paint it. I had to sell it. 1980 Turbo Trans Am 1970 Mustang fastback, 351C 4Bbl, auto 1988 Mustang GT, 5 speed 1983 F-150 4x4, built 302 1994 Chevy K2500 HD 4x4, 454 TBI
Use thread chasers instead of taps and dies. Taps and dies are made for cutting threads. Chasers are for repairing existing threads. I got a set from Sears years ago and use them frequently for cleaning up holes and bolts.
Use thread chasers instead of taps and dies. Taps and dies are made for cutting threads. Chasers are for repairing existing threads. I got a set from Sears years ago and use them frequently for cleaning up holes and bolts.