Early Mercury block vs 59A

To my more 'racy' FH I has a old NOS 8BA pump, but I has heard both that the new Melling is Ok ( I can't say if China made theesedays ) but all this new parts I'm always sceptical in unknow boxes and they smell China oil..
I guess this new ones are HV as the 8BA ?
On the other side I heard this engines don't really need a HV pump, and to me it make sense ( as no valve train just the crank )
On my old tractors the oilpumps from China is crap so I has reversed the old std gears and grinded the cap and make a new bushing/axle and they is like new.

In my race 426 Hemi I has a old std SAAB V4 oilpump ;- ))
 
Hey Hank,

I don't know anything about flathead oil pumps but thinking the 8BA style would be a good choice from what I read. I used a high volume Melling in my Olds engine a few years ago and felt like it pumped too much oil to the valve train. I lost oil pressure when the galley plug blew out and damaged my engine. I decided that the oe pump was fine so I went back to that. By the way, what kind of tractors do you mess with? I have 3 old Fords myself.

Al Hook
 
I can’t say on the FH but your story make sense on pump.
I had 3 of the 40’s Ferguson tractors with the Continental engines.
I sold the 48 but still has two 1947, one patina and one painted, both overgone totally and std.

Here is the Merc 41 short block 40 over.
Its told be dirty and wear but if to much surface rust to not go clean + 1/8 over std ( I can’t say but a nice pan ) and 300 US.
 

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3W Hank said:
I can’t say on the FH but your story make sense on pump.
I had 3 of the 40’s Ferguson tractors with the Continental engines.
I sold the 48 but still has two 1947, one patina and one painted, both overgone totally and std.

Here is the Merc 41 short block 40 over.
Its told be dirty and wear but if to much surface rust to not go clean + 1/8 over std ( I can’t say but a nice pan ) and 300 US.
Click to expand...
586622


586623
 
I think the idea that the pre-war Mercury blocks were more desirable for hot rodding came from two factors:
1 - cost; if you wanted a 3 3/16 bore flathead block to use for your hotrod build in 1948, then starting with a worn out pre-war Mercury block was a lot cheaper than buying a 59 series engine from an almost new car.
2 - visually the cylinder walls look thick; sonic testing in the last decade or two has shown the 99 block walls not to be any thicker than 59 and 8BA cylinder walls, but that information wasn't available until decades after the flathead dominate era had ended.
 
Hot rodders back in the flathead era, knew that larger bore and stroke were the best way to get horsepower so they bored them as far as they could go which could be as far as a 3-3/8" overbore but that leaves no room for overhauls. In a time when good blocks were as easy to come by as going to the nearest salvage yard, practicality was out the window. In modern times, the increasing rarity of good blocks adds a lot of practicality to the picture. Boring any engine as far as it will go will lower the longevity to extremes. More and more of these old engines require full sleeves to get further use out of such an old design and that's expensive. Until someone produces new blocks, we have to keep that in mind.
 
My other Merc 41 block is sonictested ( in US by seller ) and good at 1/8" over std but it needed 1 sleeve. So one never know how they is inside ofcourse even if thickness shows Ok.
1/8 over is feel Ok as a 1/8 over crank.

I has found 41 block here in Sweden and it was a imports from a USA car and been storage since 1995. So no water has been there for over 30 years, but the case it has 8 sleeves in it ?
I wonder, how can it be as no one could had this ideas on the 80's or 90's ( or before do this )
Very odd. Ideas ?
 

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I've sonic tested pre-war Mercury blocks, WWII industrial block (like the 41-42 Mercury, but with a factory relief), 59x blocks, 59L blocks and 8BA blocks. I've seen no definitive proof that the early blocks had thicker walls or better material. One has to be careful with blocks that have a lot of rust in the water jackets - that can spell trouble for a big overbore.

The block in my 32 Cabriolet was a NOS WWII industrial engine - same as 41-42 Merc (no casting/cleanout soft plugs in the pan-rails).

I just picked up another 41-42 WWII block 2 weeks ago . . . it is STD bore and appears to have been magged. It is the best "looking" block I've seen in 50+ years (except for the NOS one). I will have it cleaned/magged once again, then pressure tested . . . then who knows! LOL
 
3W Hank said:
My other Merc 41 block is sonictested ( in US by seller ) and good at 1/8" over std but it needed 1 sleeve. So one never know how they is inside ofcourse even if thickness shows Ok.
1/8 over is feel Ok as a 1/8 over crank.

I has found 41 block here in Sweden and it was a imports from a USA car and been storage since 1995. So no water has been there for over 30 years, but the case it has 8 sleeves in it ?
I wonder, how can it be as no one could had this ideas on the 80-s or 90's ( or before do this )
Very odd. Ideas ?
Click to expand...
586754
 
3W Hank said:
My other Merc 41 block is sonictested ( in US by seller ) and good at 1/8" over std but it needed 1 sleeve. So one never know how they is inside ofcourse even if thickness shows Ok.
1/8 over is feel Ok as a 1/8 over crank.

I has found 41 block here in Sweden and it was a imports from a USA car and been storage since 1995. So no water has been there for over 30 years, but the case it has 8 sleeves in it ?
I wonder, how can it be as no one could had this ideas on the 80-s or 90's ( or before do this )
Very odd. Ideas ?
Click to expand...

Sleeves have been around for a very long time. Ford sold them with a part number from at least 1937 on.
 
Tim Ayers said:
Wasn't there a time when Ford blocks were tinned (thin) sleeved from the factory?
Click to expand...

Correct Tim. I have owned V8/60 , 3 1/16 bore and 3 3/16 bore engines all with factory thin wall sleeves. I have NOS. Sleeves for all 3 sizes. I also have a bunch of genuine Ford Thick sleeves in their original boxes.
 
I had a older 30's block wih factory thin walls sleeves, but its was totally rusted out from inside.

Yesterday I heard ( from one source ) that the very early Mercury blocks ( 1939/1940 ) was the same as the 41 but had not the rised intake.
-Is that correct ?

I don't think the 41 block was sleeved from factory, but (?)
I will today get the bore of that block.
 
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Bored&Stroked.
Like to sell it ?

Do you know of the Merc 39/40 had no rised intake surface ?

On cylinder thicknesss I guess the only one could tell this is the guy who bored max this blocks on late 40's and early 50's if they just noted the early Merc's had a tad more.
On material, well what rings concerns is just more matter on honing, but I guess back then it was no 1 mm rings and plateu honing, but people has been clever so who knows all trix in the book that is old news.
 
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I do not believe the 39/40 Merc blocks had the raised intake surface. (which really wasn't raised, they just removed material around it).

I'll not sell this block I just acquired - is only the second really good one I've ever owned. ;)

Back in the day, many folks touted the 39-42 Merc blocks (and WWII industrial ones) as the "Cat's ***" for building a big-cube race motor. They were often referred to as "keystone blocks". I think the claims of them being "better, thicker, more nickel" were just another set of the many Flathead myths that were often repeated.

In the 59X series, they changed the valve angle and moved the valves a bit further away from the valve pockets. Some folks think this reduces the chance of cracking in the transfer area . . . but who the Hell knows.

If you have a good block and especially if all the timely porting/relieving work is done . . . I say use it!
 
Sleeved Block: If those are the thin-wall sleeves, then knock them out and bore the block as you would a non-sleeved one. If they are the thick sleeves, then your options are more limited.

Ford didn't like to scrap things . . . they "saved" blocks in a variety of ways.

Things like oversized cam bearings is one example . . .

They also welded up small flaws on some blocks - have seen this quite a few times (especially in small areas of the pan rails).
 
I has one very cool ported 41 block 1/8 over but I need another as I build 2 engines both racy but one more for street.

I still not has the bore diameter of that 8 sleeved 41 block, maybe Ford did it (?) and from pictures the sleeve look thin ( I will soon know, plus it's in Sweden )
I had the same idea and maybe if nothing bad behind I might could just hone it.
But no need speculate now.

I also found 2 1941 blocks bored not ported ( in USA ) but reparied, it might be Ok, but it's hard if welded ( I will see )

On factory repair I seen that on the Ferguson Continential late 40's engines to, brass welded and very nice done and instead of a cast issue and throw it the factory fixed it.
No one here beleived me, as they mean a later repair but it's factory ( as I see it )
 
3W Hank said:
I had a older 30's block wih factory thin walls sleeves, but its was totally rusted out from inside.

Yesterday I heard ( from one source ) that the very early Mercury blocks ( 1939/1940 ) was the same as the 41 but had not the rised intake.
-Is that correct ?

I don't think the 41 block was sleeved from factory, but (?)
I will today get the bore of that block.
Click to expand...

Correct. The 1939 and 1940 Mercury “99” blocks did not have the “raised intake area” that you see in 1941 and 1942 Mercury blocks. I’m extremely fortunate to have acquired a NOS 1941 Mercury block from a Fordbarn member that will be used one day soon.
 
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