I'm in the process of assembling the bottom end of my flathead engine. (C59A - Canadian) I have a set of French connecting rods and a set of ARP rod nuts. The 8BA rods that I was going to use originaly have "lock washers" (they sit under the rod nuts with two "bend over tabs") that are folded up over the sides of the nut after they are installed. The ARP rod nuts have a larger base (that comes in contact with the cap) and as a result the "lock tabs" just barely fold over the base to come in contact with the sides of the nuts. Can these "lock washers" be eliminated?
Do you have enogh room to install 'PAL' nuts? Those are the stamped sheet metal lock nuts that go on after the rod nuts are installed. 3/8 - NF if I remember right. Seen em in more than a few stock engines and they must work ok. Never saw a rod nut backed off in a 'PAL' nut equipped engine. The Rocket guys would know - I think they were used on the early 303" V8's.
Thanks Jay. [ QUOTE ] Do you have enogh room to install 'PAL' nuts? Those are the stamped sheet metal lock nuts that go on after the rod nuts are installed. 3/8 - NF if I remember right. [/ QUOTE ] Now that I think about it, several sets of rods (flathead) that I have disassembled had the "PAL" nuts. Your right the thread is 3/8th's NF. There isn't much thread left after the ARP nuts are in place, but I think I can "squeeze" them on. [ QUOTE ] Seen em in more than a few stock engines and they must work ok. Never saw a rod nut backed off in a 'PAL' nut equipped engine. The Rocket guys would know - I think they were used on the early 303" V8's. [/ QUOTE ] Next question: what would/should they be tourqued to?? (after the rod nuds are tourqued)
[ QUOTE ] Dave,I have never had a problem with a little red locktite. [/ QUOTE ] Thanks Flatdog; guess the 'ole brain hasn't "kicked into gear yet!" (only on second cup of coffee!!) Forgot about that one!
Just a small tip but one I've used when using locktite. Put it on the threads one or two threads from the end of the bolt. Use a tooth pick to wipe it on the threads, so you don't apply too much and it runs all over. You don't want a lot of excess that can spread around where it's not wanted (makes a mess and could get to places where it wouldn't be welcome). That way when you thread on the nut the nut will pick up the locktite and distribute it on the threads "only" as it is torqued into place.
[ QUOTE ] Now that I think about it, several sets of rods (flathead) that I have disassembled had the "PAL" nuts. Your right the thread is 3/8th's NF. There isn't much thread left after the ARP nuts are in place, but I think I can "squeeze" them on. Quote: -------------------------------------------------------------------------------- Seen em in more than a few stock engines and they must work ok. Never saw a rod nut backed off in a 'PAL' nut equipped engine. The Rocket guys would know - I think they were used on the early 303" V8's. -------------------------------------------------------------------------------- Next question: what would/should they be tourqued to?? (after the rod nuds are tourqued) [/ QUOTE ] Far as I know the end with the thread on it goes up against the rod nut. The other way round would probable allow the PAL nut to open up and not lock. I don't have my manual to look up - if any - torque fittings are listed for the PAL nuts, but snugging them up with a short 9/16" box end ought to do it. You'll know you've gone too far if you peel the thread out of the PAL nut....
Also, I wouldn't use the foldy things under special nuts--they are likely too soft in comparison to the nuts, and so may wallow out and leave you with substantially loosened rods.
I don't know about you'se guys but I don't want any little tin parts on my rod bolts/nuts. Just an off chance they could fatigue after 40-70 years and get in a spot where they could really do damage. I always use a little dab of red loctite too but just a smidgen. There have been studies where it's said the red loctite, if over-used, can get between the rod and it's cap, causing a lack of heat transfer between the two parts. Supposedly, this difference of temperatures can cause the two parts to work against each other and cause uneven torque problems.... Be stingy with the loctite and you'll be ok.
The Jalopy Journal
