Rod bolts frozen - or so it seems
 

Picked up a set of prepped '63-5 forgings from FB, with the cloverleaf pad and the faint "GM" in the beam. Look very nice - beams are ground and polished, shot peened from the texture, maybe even beaded. I know- they're 'soft' but my build won't spin past 5500.

Good news: bolts look like ARP

Bad news: clamped them in the vise, and the bolts ain't budging.

To anticipate a question, yes righty tighty lefty loosey. Check.

Before I hit them with the impact, any suggestions? There was very minor rust spotting from what I presume may have been garage/shed moisture, but nothing consequential.

Thanks in advance.

DO NOT USE AN IMPACT ON THE FASTENERS.

Put a "cheater" on the end of your Breaker Bar. A "Cheater" being a 3 foot length of heavy wall pipe that just fits over the Breaker Bar Handle.
The "Cheater" needs to cover 1/2 of the Breaker Bar handle length, the other half of the "Cheater" gives you a lot more leverage.

The rods need to be in a vice solidly attached to a bench and a aluminum plate on either side of the big end of the rod.

Tom V.

I have a few of those early rods left from a motor that had them in them and two of them let go at only 5000 rpm on the street!
I had polished them , took a ton of weight off the balancing pad on the big end and the shop that resized them installed ARP bolts also.

I hope you running them in a motor with less then a the 4.21” of a 455 like I ran mine in, other wise I would resell those and get the cheapest new manufactured forged rod and them you’ii be safe from losing a whole short block like I did!

Try a little heat on the nuts first.....
 

We've disassembled a couple of other builder's engines and found RED Loctite had been used on the rod nuts. Luckily there was a little left besides what was between the nut and bolt, so it was visible.

We used a basic propane torch and heated just until we got a little puff of smoke - that indicates that the Loctite has released. Then the nuts could be removed normally and tossed in the nearest recycle bin.

Otherwise - as pointed out DO NOT USE AN IMPACT. A cheater is your friend.

And, as also pointed out, I wouldn't use those rods in any build of mine. It's too easy to buy new, inexpensive forged rods and too expensive to do this all over again.....

Good luck!

Have used blue before but prefer to avoid red.

There is not any 3/8 nut that can not be taken off with a basic 1/2" ratchet with a long handle. Red Locktight or not. Even so, red goes away at only 400 degrees. But there is no reason to heat it.
I used red on SD 455 nuts for years and simply removed them with a ratchet.

AND, cast rods are better. Never use one of those old rods unless a early or late SD rod period.
A cheap 400$ H beam is better than any factory PMD rod ever made. (after you check them for size)

Curious. What is wrong with an impact. too much stress?

If ARP bolts are used and the nuts were installed without lube the threads could be galled

AGREE. I knew a guy in the dealership who built Turbo Hydro Trans for a living.
He had 3 times the comebacks that the other mechanics had and that Zip Gun
bought him nothing at the end of the day.

I was taught to do it slowly, carefully, and ONCE, with the other guy as an example of how not to do the job.

Tom V.

Let’s be realistic here!

If the preloading of the bolt by the tightening of the nut , or just the preload tightening of the bolt( if it’s that type of rod ) is not enough to keep the rod ends clamped up to each other, which keeps the nut from backing off then no amount of Loctite is going to help out!
Also just using Loctite on rod bolt threads means you will get accurate torque readings without over stretching the bolt,

Some torque the fastener (be it a nut and bolt, or just a bolt) to a given value, hopefully the one
recommended by the rod manufacturer, to STRETCH the fastener (BOLT) to a given length increase of the Bolt.

I always verify this bolt stretch with the proper tool made for this checking step.

Some rod manufacturers say use their rod assembly lube so that the installed rod matches the shape of the rod when it was machined by the rod maker.

If you have the correct fastener stretch then the need for loctite is not necessary or you do not have the proper stretch, ........ then you need new fasteners.

Torqueing the fastener does not actually tell you if the fastener has been over-stretched and is ready for failure.
A stretch tool WILL tell you if you need to replace a fastener.

Several rod manufacturers tell you how many times their fasteners can be stretched before they need to be replaced.

Many times I have found that the torque of the fastener needs to be increased due to variability in the torque wrench,
be it beam or a clicking type tool.
How many of you have actually had your clicking torque wrench certified by the manufacturer (like Snap-on) after a few years.
We verified the reading were accurate every 6 months at work. Course we were building engines every day. Something to think about.

Tom V.

The only early forgings I know of were the '58-62 rods.:confused:

Good point Jack!

The OP may have the forged 63 to 66 421 Rods which some say are weaker then the standard production 58 thru 62 Rods!

I had one set of the poor steel 421 connecting rods.
Tested them with a Rockwell C tester and they were very soft material.
HRC (Hardness Rockwell C) vs HRB (Hardness Rockwell B).

More info here:
https://en.wikipedia.org/wiki/Rockwell_scale

Without reading all of the info here is a quick snapshot:

HRB 100 1⁄16 in (1.59 mm) ball Copper alloys, soft steels, aluminum alloys, malleable iron 130 500

HRC 150 spheroconical diamond† Steel, hard cast irons, pearlitic malleable iron, titanium, deep case-hardened steel,
other materials harder than 100 HRB 100 500

We used to call them Pontiac "Rubber Rods"

Tom V.

I gave them to a Lake Michigan guy to use as the "weight end" of a "Seine Net" to catch bait fish.

I traded a full set of 62 389 rods to a guy for a 1971 .030 400 block. Block is a little rough, might need one sleeve do to pitting. I still got the better end of the deal.

Years ago I did a test on a rod from a 390 FE engine I was building for a guy. The rods were resized with ARP studs. I torqued them with ARP lube and made a little mark on the nut and rod with a carbide tipped awl. Then did the same thing with Red Locktight then plain grease. The scratch lines lined up with all 3 lubricants the same.
I only used red locktight on used studs and nuts as a precaution. The SD rods I had were new with new studs but the nuts were used.
Never would use it on a cap screw bolt. Asking for trouble. You can heat that little nut on a stud no big deal. But heating that rod on a cap screw would not be a good idea.