strausbo 2 #1 Posted December 11, 2010 I was wondering what the general feeling is regarding replacing the head bolts when rebuilding a K-series? I just rebuilt a K-241 and used the original head bolts during reassembly? Should I have replaced the head bolts? :ychain: Share this post Link to post Share on other sites
Polaris2007 4 #2 Posted December 12, 2010 In my opinion you do not have to replace the head bolts as long as the threads are nice and smooth and rust free. If the threads are rusty, or look anything other than new, you might not get accurate tensioning of the bolt when you torque it to spec. As for the bolt failing because it was not replaced, Have you ever seen a correctly torqued head bolt on a K-series just break during service because it was old? Me either. I'm sure I've opened a can of worms here... :ychain: Share this post Link to post Share on other sites
KC9KAS 4,741 #3 Posted December 12, 2010 Unless they looked questionable, I would think reuse would be fine. You did properly torque them and use a new head gasket, didn't you? I work for Jasper Engines (remanufacture of drive train componets), and our engines are warrentied for 3 years/100,000 miles, and the head bolts are reused! ( I actually work in the environmental department, but know about other areas of the plant!) Share this post Link to post Share on other sites
TT-(Moderator) 1,127 #4 Posted December 12, 2010 They're plain-old grade 5 bolts, not anything special like those stupid "torque-to-yield" contraptions that some #?*!&% dreamed up. It's not like you're trying to contain astronomical cylinder pressures on these old flatheads, so the biggest reason the bolts need torqued equally is so the aluminum head doesn't warp when it's tightened. As long as the bolts look good and will take the torque, there's no reason they can't be reused. I normally clean them on a wire wheel and apply a little dab of high-temperature anti-seize so they come out for the next guy ~ in another 20 or 30 years. Either way, don't forget to re-torque the head bolts after the engine has been heated up and cools again. Share this post Link to post Share on other sites
linen beige 14 #5 Posted December 13, 2010 I re use most of them. I do, however clean the threads with a die and also the hole threads with a tap before I reassemble. Share this post Link to post Share on other sites
wheelhorse656 20 #6 Posted December 13, 2010 i do the same as linen beige its useually fine i did have one brake on me one time when i retorqued the head back down. Share this post Link to post Share on other sites
strausbo 2 #7 Posted December 14, 2010 I think the main concern on reusing head bolts is the amount of stretch they have already yielded to. Share this post Link to post Share on other sites
