Inliners International Forums General Discussion Engines chevy 235/261 timing cover bolts?

So I had this engine rebuilt a while ago, and I ordered the stainless steel bolt kit for the motor from tom langdon, and it has all the bolts for the timing cover minus the two at the very bottom once its installed-its the two that go into the heavy tab piece of metal that's welded onto the cover. Well the new kit doesn't have it, and I don't know where my old ones are, so my question is how long are these bolts supposed to be, and are they just bolts that only go in just a bit and thread to the backing right behind the cover? Thanks in advance?

The stock 1/4th inch bolts come from the inside and thread into the timing cover. The standard mod is to drill the threaded holes in the timing cover out to 5/16ths and thread the block for a 5/16ths bolt so you can pull the timing cover without removing the oil pan.

Tim

Here is an illustrated guide to replacing the lower two cap screws with cap screws that thread into the front main bearing cap, as Tim suggested. I believe that the two lower stock cap screws are 5/16-18, and the new ones will be 3/8-16.

Yup, what Hoyt said.

Tim

geez bad news lol I have one of those chrome plated timing covers that they sell online and I grabbed some 5/16 18 bolts and they seemed kinda tight going in but I just figured it was chrome in the threads, I was tightening them in and they got tighter and tighter and finally the brand new stainless bolt I bought snapped in half and part of the bolt is stuck in the cover lol and now i dont know if the threads are trashed too much to use, or I have to seal those bolts with some other configuration, any ideas why this craziness happened?

You now have the opportunity to convert to the external cap screws, after the broken 5/16 thread is drilled out. We've probably all learned the hard way that if a bolt is hard to turn in it's time to back it out and find out why. I know that I have had the same sinking feeling. Was anti-seize compound on the threads? It probably would not have prevented this problem, but I use it with stainless steel screws unless they are going into cast iron.

Is this the 261 that you've been building for the past few years?

yeah Hoyt it sure is lol, I had it put in the shop a few years ago and just left in the bag in the garage ever since, last summer I was just too burned out from the college year (hard knocks for a cellular/molecular bio and microbio double major lol. This summer i decided it was time to get things done. Last winter I had a good buddy of mine port and polish an 848 head for 180 bucks lol and he did a good job, had it decked 50 thousandths, put new exhaust valves and hardened seats put in, unshrouded the exhaust valve to the inner combustion chamber area. Had new springs and keepers put in (oh side note people should have their springs load tested before they install them, my never before installed 'brand new' springs were all over place load wise and couldnt use them, had to get new ones). Next I am rebuilding my truck to get ready for the new motor-lots on my plate but the motor is coming along and looks great!