Puzzled on which bearings to buy

D

DWester

Member
A while back, we established that I have a 46-48 (59) flathead. Now I'm looking for the bearings for it and have found confusing listings. Some say they have bearings for 39-48, while others have 48-53.

Can you guys clear this up for me? That is if I happened to have a 48.
 
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If the connecting rods are the original 46-48 style the bearings wiil be of the "full floating" style with 2 halves serving 2 rods on a journal. This is the 39-48 bearing for 2.138 journal diameter.

If the rods and crank have been changed to the 48-53 style with insert bearings 2 halves will serve only one rod.
 
OK. The crank must have been updated, because the bearings were NOT free floating and were individual on each rod and notched.



Thanks, I appreciate the help.
 
And, just to help with 'confusion', not ALL 59-series engines came with floating bearings. There are a few 59-series engines that came originally, from day-one, with 8BA rods, cranks, bearings, and valves. It's possible that you might have one of those, or, as JWL says, it may have been changed to 8BA-style.
My 47 came to me with one of these engines, 59-series block, with 8BA-style innards. It's still standard bore, and I'm assuming that the innards are what came with it. Another oddity is that it does NOT have valve seat inserts - something that many folks on this forum say 'can-not-be', as 59-series blocks are 'supposed to have valve seat inserts'.
Speculation, here and elsewhere, is that my engine was likely a 'replacement' engine, sold over the parts counter, 1949 or newer. Thus, the 8BA innards, and no valve seat rings. Just opinion, no facts.
(BTW, if you are buying bearings, I think you will find that the mains are '59' (go with the block). and the rods are 8BA (go with the rods & crank.)
 
8BA was intro'd in 48 for the trucks. So 8BA style (separate bearings, two per rod) run from 48-53.

59A continued to 48 in the cars so the fully floating bearings run up to 48.

If you have separate shells you should have 8BA rods, and hopefully an 8BA crank too. The 8BA has two oil holes per journal (one for each rod) the 59A only has one. I have read that people have ran 8BA rods on a 59A crank, but it's probably not the best way to go.

The mains for the 59A have a wider tang on the rear main. 8BA mains will not fit the rear main. Centre and front are common.

Mart.
 
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I'm pretty sure that 59 engines were built for a few years after production use to feed the parts sales, and I suspect that the ones with locked rod bearings and no seat inserts were built during 8BA days. I also think that the 59's with lots of extra foundry numbers on the bell are post-production engines. No proof.
I own a '48 Ford, and I have a tip for parts purchasing: If you are not picking the parts yourself, tell them that you have a '47 Ford. I learned loooong ago that parts guys frequently messed things up when they got to that '48 overlap in the parts books and chose from the truck listing...
If I had a '48 truck, I would for sure tell the guy it was a '49!

(PS...choose all bearings based on crank you have!)
 
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Gotta disagree on the PS there, Bruce. Rod bearings, yes, but mains have to match the block, which in this case is assumed to be a 59A.

Mart.
 
And a question,why was the width of the rear main housing changed on the 8ba engines?
Lawrie
 
This is the block I'm working with. So I would need mains for this 59A block and rod bearings for an 8BA, 49-53? The crank that was in it does have two oil holes per journal.
 

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DWester said:
This is the block I'm working with. So I would need mains for this 59A block and rod bearings for an 8BA, 49-53? The crank that was in it does have two oil holes per journal.
Click to expand...

I'd say so, yes, I'd check the rear main journal for a wide tang just as a "sanity check" before ordering. Do you think the engine came from the factory with that crank?

Mart.
 
I have no idea Mart. I found it under a hood out in a field. It appears that it's been worked over. It also has the newer distributor setup too. The cylinders are in great shape, no ridge at all, measuring 3 3/16th. The pistons are standard with STD on them. It's hard to figure this thing out. You'd think if they went through it with a newer crank, dizzy, etc, that it would've been bored once at least??? Or, was it made this way new????? It does have 8rt on the heads and intake, so we are talking truck if they're original.
 
bobH said:
And, just to help with 'confusion', not ALL 59-series engines came with floating bearings. There are a few 59-series engines that came originally, from day-one, with 8BA rods, cranks, bearings, and valves. It's possible that you might have one of those, or, as JWL says, it may have been changed to 8BA-style.
My 47 came to me with one of these engines, 59-series block, with 8BA-style innards. It's still standard bore, and I'm assuming that the innards are what came with it. Another oddity is that it does NOT have valve seat inserts - something that many folks on this forum say 'can-not-be', as 59-series blocks are 'supposed to have valve seat inserts'.
Speculation, here and elsewhere, is that my engine was likely a 'replacement' engine, sold over the parts counter, 1949 or newer. Thus, the 8BA innards, and no valve seat rings. Just opinion, no facts.
(BTW, if you are buying bearings, I think you will find that the mains are '59' (go with the block). and the rods are 8BA (go with the rods & crank.)
Click to expand...


Ford Canada built a lot of 221 and 239 military engines with insert bearings and cranks with two holes per journal, and according to the Ford Canada Chassis catalog, in '46, the only engine still using floating bearings was the 99A used in the bus. There were no Ford six cylinder engines until '56, but The C51A and C59A were both available in most postwar models, the C59A only in the biggest trucks and Mercury and Monarch.
As these engines were going through the rebuilding process after '49, they would have replaced the earlier rods and thick insert bearings with 8BA parts.
 
8RT heads should not be on that block. the 8BA/8RT design has an extra water passage at the front that turns through 90 degrees and connects into the top of the water pumps. It sounds like someone really used a lot of mix and match parts when they slung this one together. That said, having the later crank and rods is a plus in my book.

The German Ford and French blocks have a hybrid block with 8BA style deck faces and front end but retaining 59 style half bell on the rear. But with that big 59 on the half bell on your block, you have to assume that is indeed a 59 style block. If you think it may be some sort of oddball 59/8ba type crossover, and you want to order main bearings it would be safer to measure the length of the bearing surface (front to rear) of the rear main. That is the difference between 8BA and 59 blocks, and why you need to get the right bearings.

FWIW French blocks use 59A type mains.

I would visually check a few things to make sure it is a true 59A block.
Wide tang in rear main
No water ports between deck and water pump tops.
Oil feeds for bushed water pumps.

Mart.
 
I've stripped a couple of engine in my lifetime with 8BA rods single bearings with a 59 crank, one oil hole. I was surprised the bearings looked good but I wouldn't rebuild it that way. btw, 39-42 had 2in. rod journals. 46 to 53 had 2.139 journals. Walt
 
39-42 239 ci flatheads had 2.139 rod journals--pre-war 99 block--post-war 59 -same

BTW Happy belated Birthday Walt!
You are a great engine builder!
When was your last 1939-1942 Merc engine build?
Gene Tulsa
 
Barlea Are you in Canada?

re Canada 221 military engines: Did they make 2 oil-hole rod journal cranks
with tabbed individual rod bearings with 2" journals ?--to fit thru bore.

Did the c51a have 2" rod journals?
I have a USA 221ci 59 (41A parts eng I guess) with 2" floating rod bearings

Good thread! Interesting.
Gene Tulsa
 
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Mart said:
I would visually check a few things to make sure it is a true 59A block.
Wide tang in rear main
No water ports between deck and water pump tops.
Oil feeds for bushed water pumps.

Mart.
Click to expand...

The tang is 1/2" wide and the rear main measures 2". What does the 8ba measure out of curiosity?
 
G32 said:
Barlea Are you in Canada?

re Canada 221 military engines: Did they make 2 oil-hole rod journal cranks
with tabbed individual rod bearings with 2" journals ?--to fit thru bore.

Did the c51a have 2" rod journals?
I have a USA 221ci 59 (041 parts eng I guess) with 2" floating rod bearings

Good thread! Interesting.
Gene Tulsa
Click to expand...

Yes, we are in the bush in west central Alberta. The '46 book shows the 221 crank, rods and bearings (locked in design) as C41A, and the 239 as C49A, suggesting 1944 design. ..B.
 
These pre 8BA Canadian cranks with the 2" Rod journals. On the Rod journal on the crank, with the two oil holes, are these holes on opposing sides of the journal, or same side like 8BA? The locked in bearings, are they thick shells with a thrust surface (lip) on the edge? Just out of interest, as a lot of the English pilot engines have these opposed holes and lip. They also have an odd mix of dimensions. The lipped bearing means long rod journals on the crank, like the earlier engines, same main journal diameter as early (2.4") but the front snout of the crank is the same length as the late cranks. I have a Pilot engine in my '42 pickup, with 8BA cam, timing gears, ignition and dual 3/8" belt pulley. On a 21 stud engine. Did the Canadian 21 studs have this odd crank?
Martin.
 
Another bit of info, the rods used in these Pilot engines, oftentimes they be 21A or 91A rods with a cut out for the tang on the bearings. The id of these rods is same as normal 21-91A rods, and have the same (on the ones I played with) surface finish as the floating bearing rods. I've seen this rods (with the tang cutout) fitted unmodified with floating bearings, seems it worked fine.
Martin.
 
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