ok guys, let me start off by saying I’m an idiot . With all the issues I’ve had this year with work and family life, I’m finally finishing the build of my 300. Installed the 6th piston tonight after getting the replacement rod bearing that was missing in the kit . Torqued the rod down and decided to double check everything . All rods good, checked the mains and found them to be loose, or so I thought. Somehow I managed to look at the wrong spec a half dozen times and tried to torque to 130. When the passenger side bolt on the #1 main didn’t torque immediately, I felt there may be an issue with my torque wrench . I had a buddy bring his by , and as I started to tighten without achieving torque, I went back a 7th time and realized I had messed up. I stretched the one bolt pretty good , but the others I started to try look ok.

Is there any issue with using a hardware store grade 8 as a replacement? I feel like it shouldn’t be an issue , but figured I would ask.

Got the head installed and realized I am missing my rockers, fulcrums , and lock nuts . Thinking back, I don’t recall getting them back from the machine shop. 😩 hope they still have them when I call Monday .

 

As a general rule these days I wouldn't trust imported from golly knows where hardware to be grade 8, why take the chance? It might be OK, but might not. Only talking a few bucks.

 

You can bet the hardware store bolts are from china. They maybe fine but.... I would go to a good parts supplier or ask the machine shop.

 

I don't know if grade 8 hardware store bolts are a good idea. You could go with studs.... but would mean you want to align hone the mains....

Google around for replacement main bolts online for the 300.

 

Im going to contact my machine shop tomorrow for my missing rockers and see if he can locate bolts. I do also have the option to go to my local copperstate nut and bolt. I wonder if their quality is any better.

 

My machine shop had main bolts and the rockers tucked away for me. Got the lower end buttoned up. Top end is almost done . Upon install of the push rods , I found 3 of them to be damaged . Once I get the replacements in hand, it will be ready to go .