Need Info-Late Crank into Early Block?

[GOSFAST]

Had a customer order a stroker kit with the mains for the 59A block.

Evidently there's an issue fitting into a very early block, 1940, and the shop, I'm assuming here, wasn't aware of this until he was way into the build??

What exactly is involved in getting this resolved if it's even possible!

To Ol' Ron, I passed along your number, hope you don't mind??

Thanks, Gary in N.Y.

P.S. Beyond the more conventional Flatheads (59A/8BA) I have less experience than many up here. Am trying to help the customer who happens to be over on the west coast!

[Seth Swoboda]

I just removed a late crank from a 1940 221ci block. I am in the process of a stock engine build for a 1940 Tudor. The rods were 8ba. The overall crankshaft length is the same as the 1940 (26.03") except the rod and main bearing journals are larger on the later crank. The problem is the big end of the 8ba rods will not go through the 3 & 1/16 bore. What procedure did the prior engine builder use to install the rod and piston assembly? No clue but it had to be a pain in the ass. I can tell you in order to remove that assembly I had to first remove the crankshaft then the rod assembly. I'm going back to 100% stock 1940 parts so I don't have any further information for you. Can it be done? Yes, apparently so.

[Brian]

That crank should fit any block from 39 onward...if the block in question is an early 38 24 stud, it will have the smaller [2.399" dia] mains, so no go ....unless you fit bigger caps and linebore to suit the 2.499 crank.

[Seth Swoboda]

Originally Posted by Brian

That crank should fit any block from 39 onward...if the block in question is an early 38 24 stud, it will have the smaller [2.399" dia] mains, so no go ....unless you fit bigger caps and linebore to suit the 2.499 crank.

My block is a 1940-1941 so the main bearing caps in my block would be compatible for the 1946-1951 crankshaft that the previous person installed? As I understand it. The rod journals are larger on the '46-'51 cranks therefore they installed the 8ba rods onto the 221ci pistons. It's quite a mix match of parts.

[flatheadmurre]

When you start to stroke them the bigend of the rods hit the bottom edge of the cylinders...trying to stick aftermarket beefier rods probably ends up with the same problem.

[Ol' Ron]

Sponsored Links (Register now to hide all advertisements)

Yes Gary, I spoke to him today. His problem was the rear seal. His block had the stinger seal system, which made me doubt the year of the block, but I don't work on many of the early blocks. However, Reds Headers has the conversion Kit to modify the rear main cap. I always thought the singer system was only used on the 2.4 crank, not the 2.5.
He might have the wrong block???

[GOSFAST]

Originally Posted by Ol' Ron

Yes Gary, I spoke to him today. His problem was the rear seal. His block had the stinger seal system, which made me doubt the year of the block, but I don't work on many of the early blocks. However, Reds Headers has the conversion Kit to modify the rear main cap. I always thought the singer system was only used on the 2.4 crank, not the 2.5.
He might have the wrong block???

Hi Ron, thanks for helping so quickly, I wanted to wait and check with you about giving out your phone number but he sounded as though he was in "panic-mode"??

He was a perfect gentleman to deal with, not a single issue.

Thanks, Gary in N.Y.

P.S. I have some reservations about the shop doing his build, they told him there were 3 broken rings in the package I sent him. I found it odd they just informed him about this when they've had the kit for some time now. I told him it sounded more like they had maybe broken some rings during the ass'y?? Guess we'll never know for sure though!

[Ol' Ron]

can't remember some of this stuff, getting old, but I wonder if he had a small main block. WE used 99A engines in the stock car with early cranks and rope seals. I have one of these cranks and it's been freshly re ground. I'll look at it tomorrow.
I don't mind helping out, gota keep these flatties runnin.

[Brian]

The die cast positive seal holders to replace the slinger style die cast pieces are; upper 91A 6335, lower 19B 6336. These are Ford part numbers. Ford supplied engines with both types rear seal/slinger arrangements up to and including 1942.

[Ol' Ron]

Does that includ the rear cap? I didn't know it had a replaceable seal holder. Learn sumpin every day. Gaary, you'd better call him.

[Dave/Green Bay]

Here are some pictures of Reds rear conversion. Was on a 35 LB so might not apply. Dave/Green Bay

https://www.fordbarn.com/forum/showthread.php?t=21404

[GOSFAST]

Originally Posted by flatheadmurre

When you start to stroke them the bigend of the rods hit the bottom edge of the cylinders...trying to stick aftermarket beefier rods probably ends up with the same problem.

With the rods we supply for the strokers there's no grinding to the bores, they fit right in with a 4.250" "arm". They MUST be checked, but so far all the ones we've built here were a "go" with no grinding. The aftermarket rods (H-beams) are also much stronger than the OEM's.

Originally Posted by Ol' Ron

Does that includ the rear cap? I didn't know it had a replaceable seal holder. Learn sumpin every day. Gaary, you'd better call him.

Hi Ron, I just spoke with him this morning, so far it seems it will all work out in the end (hopefully for his sake)??

Thanks, Gary in N.Y.

P.S. I just want to thank all who responded here one more time, appears to have paid off? If any further issues arise with this particular build I'll come back here! I still have some reservations about the shop he's using, but I can't help all that much with the distance between us.