Does anybody has the Small Block Chevy torque Engine Specifications for the motor mounts to engine motor mounts to frame motor mounts to motor mounts One a 283 and 350 engine Thanks your help. The internet gives me numbers from 35 - 60 pounds
usually 3/8" bolts (such as hold the mount or bracke to the block or frame) get 30-35 lb ft 7/16" as used for motor mount bracket to mount, would be more. But, there are several different styles, and we'd need to know what you have to give you the correct answer. I don't think I've ever used a torque wrench on either, I just get them tight.
Print a torque chart off the internet for different sizes, grades, threads, and alloys of cap screws. Put in your tool box lid or post it in garage on a cabinate door.
We had a critical piece of hardware at work that had to be very tight. We made up some sample pieces in the shop... real parts were too valuable to play with, installed the bolt and crept up on the torque until the bolt broke. Did 3 of them actually, one with never seize on it. Finally we broke it in all 3 and determined the average force was close enough to help us. From there, we backed off the torque value by 15% and have been using that since. My general torque formula is: T = Ar x k x Ftu (at a %) x Nominal Thread Diameter. Everything is in inches, answer will be in inch-lbs. Ar: is thread root area k: is coefficient of friction, .20 for dry thread, down to .14-.18 for a lubricated thread Ftu: is Ultimate tensile strength for the bolt material %: I generally use is 65%, 50% I use for more of a safety factor (not breaking a very hard bolt) Nominal Thread Diameter: is what ever the bolt is, 1/4" = .25 I apply a plus or minus 5% to what I get. This is a great source for a torque calculator. I often bounce it off my formula as a check. http://www.futek.com/boltcalc.aspx
as a general rule... if there is not a printed torque value in a service manual I tighten it until I think it is tight enough and then check it again after a few drives and heat cycles (50-100 miles) sometimes I will use the 1 finger wrench pull, 2 finger wrench pull, 3 finger wrench pull, etc, method of torqueing fasteners... hook a finger or two over the handle of the tool and pull until your finger is ready to slip off... the more fingers you use, the more torque applied...lol Chappy
another "rule of thumb" for torque, is to use a ratchet and socket with a drive size roughly the same size as the bolt. So use a 1/4" drive ratchet on 1/4" bolts, 3/8" on 3/8" bolts, and 1/2" drive on 1/2" bolts, and pull kind of hard on the handle of the ratchet to get the bolt tight. (don't do this with long handled ratchets, of course)
Fortunately most engine block threads use coarse bolts. Fine thread is tougher to estimate when you're tight/torqued.
My question why in the 60s did Chevy put the long mount to frame bolt in from factory so you had to pull the fuel pump to get to it out?
What do you guys have against split lockwashers??? Edit I recieved a PM from a HAMB friend that thought I was out of line with my original post, not saying he is right or wrong so just thought an edit was in order.
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