+40 bearings

[f1builder]

i have a 41 block in the shop, had it line bored, 4" merc crank and + 30 merc pistons. the guy at the shop says the crank will clean up at .40 for rods and mains. i haven't been able to find bearings yet. i seem to remember that going with earlier rods, like 21A or 29A, provide a smaller rod journal that might allow me to use .20 or .30 bearings? i know this sounds far fetched but i just got that thought in my head. anybody know if that is doable? or where i can get .40 bearings without selling the farm? i appreciate any help or comments. thanks, george....

[Lawrie]

I just bought a pile of early (33-34 ) bearings,Look on e/bay and ask here.some sell them, but 040 seems small,ask Walt.
Lawrie

[Mike B]

Ya asked for comments...here's mine

If I took a block/engine etc to a machine shop, and told them "turn the crank 20/20, bore the block ,040...and that's all I asked, then I'd be on the hitch to having that parts that fit.

Now if I took a block into the shop and they bored it, then told me "now ya gotta find bearings that fit...or pistons, whatever"...I'd grab my stuff and leave...heck, if they didn't inspect it first and tell you what was needed,,it's on them...

Can't provide the parts for me?...well, I'll take my toys and go home..

Why should you be on the hook for finding parts to make the rebuild successful off their recommendation?

I'm just saying, if a shop (after inspection) says "the bores will clean up to .015 but we don't have parts for that".

Well, inspect the block, crank/etc...tell me what ya can do with it....but again, if you set the criteria, it's on you.

And yes, I fully expect to pay for the time to check the stuff out.

[ford3]

i dont know where you live, but here in calif is a place that will weld up your crank throws and gring them back to standard, cheaper than buying a new crank, .040 under sized crank would make me nervous

[scooder]

Pre 59A Ford rods had 1.998-1.999" rod journal. Which is a bunch smaller than the 1939 up Merc and 1946 up Ford rods that had a 2.138-2.139" journal. So is a possibility. But the bearings are gonna be spendy. I'd be surprised if you can't turn up some old stock. 040" 8BA type bearings over there. Some one like job lot.
Martin.

[scooder]

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Originally Posted by ford3

i dont know where you live, but here in calif is a place that will weld up your crank throws and gring them back to standard, cheaper than buying a new crank, .040 under sized crank would make me nervous

Out of interest, why would a. 040 under crank make you nervous?
Martin.

[BILL WZOREK]

Originally Posted by ford3

i dont know where you live, but here in calif is a place that will weld up your crank throws and gring them back to standard, cheaper than buying a new crank, .040 under sized crank would make me nervous

Ford3:

Do you have contact info for that shop ??

[Walt Dupont--Me.]

George, you a few options, 1-keep looking for .040 8ba bearings, post on the sell swap wanted section, there is a no. of venders that have barns full of NOS stuff. 2- you may find a set of .040 for 59AB rods. 3- you may find a set for the 21A rods, don't be scared to turn the crank .040, people turn those 4in. cranks all the time to 2in. for stroking 1/8in. I had 4-1/8 stroker one time turned .040 under. Drag raced that thing and it held up fine. Walt

[f1builder]

mikeb----the crank came out of a canadian merc, 1950, and i heard the steel was better than US so i wanted to keep it. it miked out to .20 and the shop thought it would clean up at .30. the shop is very good and experienced with flatheads. they said it would clean up nice at .40 but they will run it to .30 first to see how it comes out. bob there said it may have some pitting but might still be ok at .30.

ford3---johnson machine in rapid city sd can weld it up and grind it but they charge 70. a journal + grind which would run up to around $600+ which isn't economical. there used to be a shop in spearfish which could do it much cheaper but they are closed. i wouldn't be nervous about running it .40 as i won't be racing it, it is for my 47 ford, just a daily driver.

scooder---running a crank at .40 i wouldn't be worried myself, i don't intend to race it or push it hard, just a daily driver.

walt----i heard that egge has .40 bearings but they cost a bunch. will call them tuesday to check. i haven't checked the sizing but i thought that 21A rods might change the bearing size to around .20 or so.

thank you all for your input, i wanted to save the block on this build as it came out of my 41 ford years ago and is really a nice block. just doing a mild build, using a 77B cam, + 30 bore, 2x2 w/97's, sharp heads, and some older dress up stuff.

[Walt Dupont--Me.]

The 41 Ford blocks were 3-1/16 bore with steel sleeves, You said it is bored .030, did they bore the sleeves or remove them and bore another .030? OR, is it a 41 merc block that is 3-3/16 from the factory? Walt

[barnfind08]

pm sent.

[f1builder]

walt...i will have to check with the shop, i gave him my set of merc pistons which were .30 over and that is what he bored the block to. i imagine he removed the sleeves and bored it to the piston size. i never really undertood why the 41 blocks were sleeved in the first place??? thanks, george.

[JWL]

Regarding the crankshaft----it will be worn on the bottom side of the journal. Tell the shop to move the stroke out .010 and it then wil clean up at .030. And, it will close up the deck clearance to a more reasonable dimension. I have only done this on about 200 crankshafts so it probably will work in your situation.

[Kube]

Originally Posted by ford3

i dont know where you live, but here in calif is a place that will weld up your crank throws and gring them back to standard, cheaper than buying a new crank, .040 under sized crank would make me nervous

Like you, I would be very apprehensive to use .040" bearings. In fact, I shy away from anything more than .020".
Another poster had asked "why"? Bearings that 'thick" will have a tendency to "crush".
I have yet to find a reputable builder that would dare suggest .040" is okay.

[Karl Wolf]

I would go .040 under and not worry a bit...

Karl

[Ol' Ron]

The shell is oversize and the amt of bearing materiel is the same as standard.

[ford3]

Ron, thats the way is supposed to be done, but alot of bearing manufactures dont want the expense of making new shells, so they just use a standard shell and add more babbit,years ago you could by real thick bearing and have then turned to what ever the crank was ground to, those days are gone tho

[Kube]

Originally Posted by ford3

Ron, thats the way is supposed to be done, but alot of bearing manufactures dont want the expense of making new shells, so they just use a standard shell and add more babbit,years ago you could by real thick bearing and have then turned to what ever the crank was ground to, those days are gone tho

Bingo! That's my worry...

[ford3]

Scotter, in my opinion, , i wont use a crank with a smaller (thinner) throw on the crank because the more chance of the crank flexing at that point, and the flathead with 3 main bearings the crank doesnt need any more flexing, the stiffer the crank the better, i wont use a crank ground over .020 under

[Kube]

Originally Posted by ford3

Ron, thats the way is supposed to be done, but alot of bearing manufactures dont want the expense of making new shells, so they just use a standard shell and add more babbit,years ago you could by real thick bearing and have then turned to what ever the crank was ground to, those days are gone tho

Bingo! That's my worry...