Posted by wayneh [173.245.54.42] on Thursday, February 11, 2016 at 21:36:11 :
In Reply to: To Lub Head Bolts Or Not? posted by Dean [162.158.255.164] on Thursday, February 11, 2016 at 09:18:40 :
Dean: The machine shop I work at (as a 58 year old apprentice) puts a lot of motors together ranging from 80 year old antiques to modern race engines. Technology has changed a lot since they wrote out manuals. Here is what we do.
1) Chase every threaded hole with a new/sharp tap. We put cutting grease (not oil) on the tap for each hole.
2) As I said before, if the head bolt goes into the water jacket we use high temperature permatex thread sealant on the threads. We coat the bottom 1/4" of the bolt and that is it.
3) On bolts that don't go into the block you certainly can put some oil/grease on them. Your threads are like new so it may not matter too much.
4) lots of people use ARP studs on high performance engine. They provide a special grease with the studs that you put both on the threads and where the bolt seats to the head.
On our 230 engines the biggest problem is many of the bolts are corroded and should not be used again. Look carefully at the threads and make sure they are 100% perfect. I tossed out two bad head bolts for every one we used.
The owner of the shop insists on using copper head gasket. We torque them in three stages with a calibrated torque wrench. Start at 40 and I think ours end at 70 or so. (The bolts with the threaded nuts actually have a slightly different torque value)
Did I mention use permatex high temp thread sealant!!!
Good luck.
Wayne
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