Question about NOS connecting rods

R

rrosm99

Junior Member
Bought a set of NOS 29A-6200 connecting rods for my dad who is rebulding a 39 ford tudor deluxe. They were sealed and wrapped in grease/ wax paper (which is a pain to clean up). He was wondering if anyone knows about the white paint marking on the one side of the upper con rods. Each one has it in roughly the same spot. What does it mean? Face this side to the front??
Any ideas??
 
Word of warning. Whenever obtaining "NOS" or rebuilt Ford rods that use full-floating bearings, be sure to check the dimensions of the piston pin bushings and the diameter of the crank journal end. What may look NOS may have been rebuilt instead and have non-original configurations. Many pistons were reused (rebuilt) by fitting oversize piston pins and required honing the pistons and rod bushings to fit. Also the conn rod crank ends could have been resized to a larger diameter to only accept special oversize bearings that would also have to be of a size to fit any crank grinding changes. (these bearings can be difficult/expensive to obtain now).
 
Hi all; Also remember that surplus V8 military parts are in the supply chain since ww2. Newc
 
Check for roundness on big ends and balance. Apparently your Dads 39 Ford has a later engine to be using 29A rods ..
 
Ken is right. Either the engine is from a Merc or truck or a later model Ford to need 29A rods which are for the larger rod journal diameter.

Ford used color codes to identify components which met a certain size or weight or other configuration requirement. All being white in color would seem to indicate a set matched to a certain specification. However, as others have mentioned, give them a good examination.
 
As a couple guys mentioned, if he is restoring the correct engine for his car, then it came from the factory at 221 cubic inches (Ford) and used a smaller diameter journal on the rods. If the crankshaft has the 1.998 rod journals, then you'll be needing the '91a' or '21a' full-floater rods and bearings. If you don't already have these items, you'll spend more money on the rods and bearings than you would just finding a later crankshaft, rods and modern type rod bearings. (49-53).

Truth be told, unless somebody really knows how to setup the full-floater bearings, you'd be better off with a later 49-53 Ford crankshaft and a set of later 8BA - 49-53 rods. This later setup uses more "normal" insert bearings (which are cheap and readily available). You can buy a new set of these rods for about $225 and even new crankshafts from San Francisco Flatheads.

http://www.sfflatheads.com/home/

There are plenty of used cranks/rods available for 49-53 Fords - or you can 'step up' to a Merc crankshaft for a bit more money (and cubic inches).

If you want the details on any of this, just PM me.
 
Bored&Stroked said:
As a couple guys mentioned, if he is restoring the correct engine for his car, then it came from the factory at 221 cubic inches (Ford) and used a smaller diameter journal on the rods. If the crankshaft has the 1.998 rod journals, then you'll be needing the '91a' or '21a' full-floater rods and bearings. If you don't already have these items, you'll spend more money on the rods and bearings than you would just finding a later crankshaft, rods and modern type rod bearings. (49-53).

Truth be told, unless somebody really knows how to setup the full-floater bearings, you'd be better off with a later 49-53 Ford crankshaft and a set of later 8BA - 49-53 rods. This later setup uses more "normal" insert bearings (which are cheap and readily available). You can buy a new set of these rods for about $225 and even new crankshafts from San Francisco Flatheads.

http://www.sfflatheads.com/home/

There are plenty of used cranks/rods available for 49-53 Fords - or you can 'step up' to a Merc crankshaft for a bit more money (and cubic inches).

If you want the details on any of this, just PM me.
Click to expand...

The larger journal crank will require a 3 3/16 vs the stock 3 1/16 bore size.
 
Ken/Alabama said:
The larger journal crank will require a 3 3/16 vs the stock 3 1/16 bore size.
Click to expand...

Ken is right in reference to the rod being able to fit through the bore from the deck side. Typically you'd bore the block to 3 3/16, or if it has the "tin-can" knock-in sleeves, then you'd take them out, then bore the block. You already have that issue in the the 29A rods are also designed for the bigger-bore block.
 
Was out at my dad's today and the rods are actually a 21A-6200 set. I got it wrong when I wrote my first question. They came out of a sealed box as a set of eight, each boxed as pairs in four individual boxes inside the sealed case. He was guessing them as military surplus but does it matter?
 
rrosm99 said:
Was out at my dad's today and the rods are actually a 21A-6200 set. I got it wrong when I wrote my first question. They came out of a sealed box as a set of eight, each boxed as pairs in four individual boxes inside the sealed case. He was guessing them as military surplus but does it matter?
Click to expand...
Interesting that your 21A rods have "White" paint on them . I have several NOS sets of 21A rods & they all have "Yellow" paint . I always figured it was from a factory "QC" process.
Goodluck with your build !
Cheers
Tony
 
You must log in or register to reply here.
Back
Top