Head bolts on Kohler K321

[cadman60]

I just started working on a garden tractor with a Kohler K321 engine that has a blown head gasket. I plan on putting in new Gr. 8 bolts, cleaning carbon off head and top of piston and truing the head if it is warped, and cleaning the tapped holes in the block. My question is do I put the head bolts in dry or put some type of lubricant on the threads? I've done some searching and found a spectrum of things to do, from installing head bolts dry, putting oil on the bolt threads, put a small dab of never-seez at the end of threads, spray wd-40 on the threads, to putting oil on the threads and then rub the bolt on a paper towel to remove most of the oil but leave the oil in the bottom of the "V"s on the bolt. What is the correct procedure on this? I know if you put any kind of lubricant on the threads it will effect the torque. I don't want to mess up or damage the engine. Thanks in advance for any help/info you can provide.

[RoyM]

I never found a need to lubricate the bolts in cast iron blocks. Just make sure the threads are clean and no debris in blind holes.

[bgsengine]

I used to rebuild these 1 to 2 a day, 5 days a week during the summer back in the late 1980's, early 1990's ... as long as bolts are clean threads, which they will be if new, and threads in block are clean, you can do what I did, when I began the rebuild, I had a pan of clean 30 weight oil in which I had the ball bearings and all the bolts soaking.... (at summertime room temperature which typically was in the 80's fahrenheit) and when I reached the point of assembling the piece that was gonna use the bolts, Id take all the bolts out and let them "drip dry" on a rag while I prepped the components, then wipe them down with a rag before use... Basically they would just have a thin film of oil (enough left by wiping off with rag, nothing dripping or running) and typically just went to the mid-range of the torque spec (if there was a range) But then most head gaskets for Kohler Cast iron were metal clads, and they didn't really have problems with "squish-out" like graphite gaskets later on did... but when they started going to graphite gaskets, I stopped soaking in oil and just run them in dry (or as dry as the parts washer left them - which was basically mineral spirits) So, if you have modernized graphite head gaskets, I'd say just run them in dry, no oil.

[cadman60]

Thanks guys for the replies. l do have a Kohler OEM head gasket that I'm going to use. Has a nice, thick metal fire ring around the cylinder opening.