21 stud rebuild (rod bearings)

[rottenron36]

Just a Heads up! Anyone thinking of rebuilding a 21 stud flathead, beware! Most parts are still available. Rod bearings are a different story and very hard to find. That is if you can find the size you need. And They are very expensive, usually over $200.00 plus shipping. PLEASE check on the parts you need before going to the machine shop. Ford Barn was the only place I could find .020 rod bearings, and that was 3 years ago. Any other input on this subject would be greatly appreciated. Thanks Ron

[Kahuna]

Ron
You are probably correct because, as I recall, the rod bearings are a flanged type.
I had read somewhere, that some of the Great Race entries used a later 4" crank, then were able to use the later. more available bearings and rods

[flatheadmurre]

Not as easy to stick a 8BA crank in an early 21 stud as in a 59ab....
$200 will not even get close to the cost of machining to drop a later crank into it.
Main bearings won´t fit, rod clearance issues, crank snout size....

[barnfind08]

I have any size you need in flanged rod bearings. Fred

[Lawrie]

Branford,would you have any 91a-6211-010
Thanks Lawrie

[barnfind08]

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Lawrence are you talking to me? I have 81A-6211C which is .010 Thanks Fred

[russcc]

For those of you that do not know. Fred Wiilner, (Barnfind08), has most of the bearings for the early V8s, NOS, not imports.

[Juergen]

Originally Posted by flatheadmurre

Not as easy to stick a 8BA crank in an early 21 stud as in a 59ab....
$200 will not even get close to the cost of machining to drop a later crank into it.
Main bearings won´t fit, rod clearance issues, crank snout size....

It did not cost me $200 to get a Mercury 4 inch crank into a 37 block. The middle main bearing cap and saddle had to be ground back 1/16 inch on each side as the later blocks were 1/8 narrower. This can be done with a 4 1/2 inch grinder as you are not messing with the thrust bearing and the 37 bearings are not as wide as the caps. Also the rear of the front main saddle and cap had to be ground back 1/16 inch. The machine work consisted of grinding the crank from 2.499 to 2.399 which allowed me to use standard main bearings (available from Van Pelt). The 8BA rods fit without mods (perhaps because I bored the engine to 3 3/16). I used a 40 Ford crank snout with the fan mount cut off. It also allowed me to use the rope seals instead of the rear slinger using the 48 die cast pieces which dropped right in.

[Juergen]

Now the Merc crank was expensive. But an 8BA crank and rods go pretty cheap (because so many blocks are cracked)..\

[Ol' Ron]

Rear seal???? I normally have to buy an adapter from Red's headers to modify the rear cap. But ya learn sumpin every day, til they through dirt on ya.

[Lawrie]

Juergen,would the 8ba rods fit in if the bore was 3-1/16,that fitting the 8ba crank in seems almost TOO easy,
Lawrie

[GOSFAST]

Originally Posted by Lawrie

Juergen,would the 8ba rods fit in if the bore was 3-1/16,that fitting the 8ba crank in seems almost TOO easy,
Lawrie

Hi Lawrie, takes a 3.180" (nominal) hole size to get an 8BA rod to pass through w/o the cap. Won't go at 3.060".

Thanks, Gary in N.Y.

P.S. The cap section of the 8BA rods measure 3.400" (nominal) across.

[voblackwood]

I have several sets of all sizes including V8-60 engines. Also NOS piston sets and NOS ring sets in all sizes. Very fair prices!!
Thanks Vernon

[Ol' Ron]

Lawrie, I think you can put the pistons on the rod when you put them up from the bottom. Then push the the pistons down on the crank. But you still have to reduce the size of the mains. Not sure if this works, but been told it will??

[Lawrie]

Well ,maybe thats an exercise I could do to see what is involved,but at the present I,m doing maint on my home,replacing the beams on my verandah,a LOT of work.
Lawrie

[Talkwrench]

You still replacing those beams Lawrie ; o P ..

[Lawrie]

Yes Rob, got 3 done yesterday ,all up about 60 to do.
Lawrie

[Talkwrench]

60 !! sweet Lord...