Engine Head Bolts - How Tight and How to Tighten?

Question: How should I tighten the head bolts on my engine? How tight is tight enough? Can I over do it?

Answer: The head bolts should be snugly tightened by hand using the small allen wrench supplied. Work in stages back and forth across the head. Do not unevenly or overtighten the bolts or you will warp the crankcase, or the head or strip or break the bolts.

Better Answer: There is a strong bias amongst modelers to overtighten head bolts and engine bolts in general. As the Operators Manual points out your engine is a precisely made piece of machinery... you are not working on a tractor here... leave your hammer, vice grips and power tools in the drawer. All you need is the allen key provided and a delicate, firm touch.

Install the head gaskets and head on to the engine. Insert the head bolts loosely into their mounting holes and screw then down so that they are loosely retaining the head. Now work in a criss cross pattern and in phases. Do not tighten any one bolt all the way down. Tighten one bolt so that it in contact with the head, now tighten the bolt across from the first on the other side of the head. Now come back and move over to the next loose bolt... go back and forth and around the head like this until all head bolts are just tight enough to touch the top of the head. Now begin again, tighten say 1/2 a turn and then jump across the head and do the say thing... criss cross and move around the head until all bolts are at the same tightness. Now go in 1/4 turn increments back and forth and around the head until you the bolts feel snug but not squeekly tight when using the allen key attached. That's it you are done! Do not overtighten the bolts!