Early Mercury block vs 59A
- Thread starter 3W Hank
- Start date
With this talk about these blocks, curious on thoughts about whether or not it's worth repairing the two 99's that I have that are cracked.
Both have the same crack. #3 intake valve through the seat into the cylinder. I'm going to tear down the third short block I have. I'm hoping it will pressure test OK, but we all know how that can go.
I guess the repair would involve pinning the crack and installing a sleeve into the cracked bore. I'm leaning on scrapping them, but would like to hear other opinions on whether I should attempt to save them. One is relieved and the other is not.
Both have the same crack. #3 intake valve through the seat into the cylinder. I'm going to tear down the third short block I have. I'm hoping it will pressure test OK, but we all know how that can go.
I guess the repair would involve pinning the crack and installing a sleeve into the cracked bore. I'm leaning on scrapping them, but would like to hear other opinions on whether I should attempt to save them. One is relieved and the other is not.
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This pittings can be as water from a crack or water from outside coming in, and it's look bad but a engine don't know that.
But all that water has created huge pittings so my guess it must be sleeved.
I has dealing with 1 8BA block 4 of the 59AB blocks all cracked, but they was Ok to be returned and not big money in them, but it's time consuming...
My experiance is cheap block on a pallet is a issue at 99%.
So what to do, bought a complete car ?
But what does that tell if a new or old repair (?)
Anyway, I found my Merc 41 block ported nice at LARS but it was a case.. . was a rapair ( but very nice done and after pressuare check it was a pit in that cylinder ( = sleeve )
It was not really cheap but I'll did like it.
Then imports to Sweden, then hottank, remove stud, install a sleeve.
Now I'm bulding a second engine ( just because I can/like do it as I don't need it )
So I like another Merc block.
The seller of my block has a ported 59 block ( pressuare checked at 500 USD )
But I like a Mercury 39/40 or a 41/42 ( rather a 1939 )
I has several ideas to find them but it's all some kind of case with them.
Why can't a nice be found ? ;- ))
I has the same experiance on older Chry 440 blocks and when I started it was 40 years ago, and they get not younger.
But it's the same on all muscle car V8 on a pallet, just issues.
But the flathead is harder ( and older )
My own racing I has new blocks ( MP ) or as my new 426 Hemi a block J.Line did cast/machine to me ( not cheap )
-But what to do with this old flathead block's ?
Well, they can be reapaired, but its a price ( in my case I has machines ) but is it worth it, but what to do, and will hobby goes on ?
Maybe all this is over in 10 years.
I guess it's up the owner as nothing is steady, and time change.
So far old parts has rised, but further on ? I'm sceptical.
The parts I bought it's pratically impossible to sell, but I has bought it as I like see parts all over me.
Maybe one day I'll just go to the crap yard.
But all that water has created huge pittings so my guess it must be sleeved.
I has dealing with 1 8BA block 4 of the 59AB blocks all cracked, but they was Ok to be returned and not big money in them, but it's time consuming...
My experiance is cheap block on a pallet is a issue at 99%.
So what to do, bought a complete car ?
But what does that tell if a new or old repair (?)
Anyway, I found my Merc 41 block ported nice at LARS but it was a case.. . was a rapair ( but very nice done and after pressuare check it was a pit in that cylinder ( = sleeve )
It was not really cheap but I'll did like it.
Then imports to Sweden, then hottank, remove stud, install a sleeve.
Now I'm bulding a second engine ( just because I can/like do it as I don't need it )
So I like another Merc block.
The seller of my block has a ported 59 block ( pressuare checked at 500 USD )
But I like a Mercury 39/40 or a 41/42 ( rather a 1939 )
I has several ideas to find them but it's all some kind of case with them.
Why can't a nice be found ? ;- ))
I has the same experiance on older Chry 440 blocks and when I started it was 40 years ago, and they get not younger.
But it's the same on all muscle car V8 on a pallet, just issues.
But the flathead is harder ( and older )
My own racing I has new blocks ( MP ) or as my new 426 Hemi a block J.Line did cast/machine to me ( not cheap )
-But what to do with this old flathead block's ?
Well, they can be reapaired, but its a price ( in my case I has machines ) but is it worth it, but what to do, and will hobby goes on ?
Maybe all this is over in 10 years.
I guess it's up the owner as nothing is steady, and time change.
So far old parts has rised, but further on ? I'm sceptical.
The parts I bought it's pratically impossible to sell, but I has bought it as I like see parts all over me.
Maybe one day I'll just go to the crap yard.
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big job
Well-known member
All I can say is in my day of oval track class A division 100% was Ford and 100% were
59ABs. I remember only one 8BA that was at the tail end and went to pole position and the flag came down the 8BAs and smoked him. I was one of four on the pit crew and I can not remember anyone losing an engine.. I say no wonder pre 1948's and back coups & 2drs are rare around here.. If you wonder why the 59As were the king I do not know..............sam good ole #93
59ABs. I remember only one 8BA that was at the tail end and went to pole position and the flag came down the 8BAs and smoked him. I was one of four on the pit crew and I can not remember anyone losing an engine.. I say no wonder pre 1948's and back coups & 2drs are rare around here.. If you wonder why the 59As were the king I do not know..............sam good ole #93
big job
Well-known member
thats an old term we use to say what it means is by a 1/2 lap the 8BA fell back almost 3/4 a lap. another term left him in the dust. good ole days
Today I picked-up the Mercury block that had 8 sleves in it, came from a car imported from USA and has been storage since mid 90's ( in Sweden )
It's std bore but it look like bore to sleeve is 3.125" or 3.1/8" or 3.5/16".
I can't say who did this, Ford or a older repair ( maybe its something behind it..
It's no crack as I can see in oilrail or from port to cylinders.
It's a '99' number ( se picture ) and a 'T' (?)
It's nothing on upper/rear of block.
Se waterpump location, details what year it can be.
I don't think it's a Canadian block.
I can't say if it's a 1939/40 block but it has no waterplugs in oil rail, plus it has the rised intake that tell me a 41/42 block ( not a 39/40 ) but the 99 'T' ?
Was not that number indicxated of the early Mercury ( 39/40 ? )
It's std bore but it look like bore to sleeve is 3.125" or 3.1/8" or 3.5/16".
I can't say who did this, Ford or a older repair ( maybe its something behind it..
It's no crack as I can see in oilrail or from port to cylinders.
It's a '99' number ( se picture ) and a 'T' (?)
It's nothing on upper/rear of block.
Se waterpump location, details what year it can be.
I don't think it's a Canadian block.
I can't say if it's a 1939/40 block but it has no waterplugs in oil rail, plus it has the rised intake that tell me a 41/42 block ( not a 39/40 ) but the 99 'T' ?
Was not that number indicxated of the early Mercury ( 39/40 ? )
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petehoovie
Well-known member
I found this information.
---------------
1939-40 Mercury
1939 saw several changes to V8 engines. The biggest changes were due to the introduction of the Mercury. The
Mercury had an engine based on the Ford V8, but with a noticeable increase in torque and a nice bump in
horsepower. The additional power came as the result of additional displacement, 239 cubic inches instead of
Ford's 221 cubic inches. The additional cubic inches came from a 1/8 inch larger bore, to 3 3/16 inches. Now
we have the reason for 24 studs per head. The lower line of studs on the 21 stud motors is too close to the bore
for safe production of 239 cubic inch motors. With the addition of more power came larger main and rod
bearings, this time 2.500 inch diameter mains and 2.140 inch diameter rods. Another difference started with
1939 motors is a longer crankshaft. Ford and Mercury mounted the engine fan on the end of the crankshaft in
1939, 1940, and 1941. To allow the fan to be held onto the snout of the crankshaft, the snout was made longer.
Starting in 1939 some V8 blocks were relieved between the valves and the bore at the factory. This was done to
reduce compression and detonation problems on large trucks. Both 3 1/16 bore and 3 3/16 bore blocks may be
factory relieved. All blocks still have four freeze plugs in the oil pan rails. Mercury blocks have round center
water holes in the decks that can be used to identify a 239 motor from the smaller Ford motors of the same
years.
The 239 cubic inch Mercury engine was also optional in trucks. The water holes in the deck feature a circular
center instead of the upside-down keystone. Some 239 blocks had 99 stamped into the passenger side intake rail
near the front, but not all. As with the LB, an unscrupulous person could have added this marking to a less
desirable engine also. The determination on one of these blocks should be made using the center water holes in
the deck. Mercury motors will have an upside-down keystone at the bottom and a circular hole in the middle.
These can be seen in the The 239 cubic inch Mercury engine was also optional in trucks. The water holes in the
deck feature a circular center instead of the upside-down keystone. Some 239 blocks had 99 stamped into the
passenger side intake rail near the front, but not all. As with the LB, an unscrupulous person could have added
this marking to a less desirable engine also. The determination on one of these blocks should be made using the
center water holes in the deck. Mercury motors will have an upside-down keystone at the bottom and a circular
hole in the middle.
The series engines got the 99 identification since they started in 1939 and displaced 239 cubic inches.
Features of the 1939-40 Mercury
24 studs retaining the cylinder heads
Water pumps in the block
The water drains are angled
Passes the pencil test
Core plugs in the oil pan rails
Crankcase ventilation
Insert main bearings 2.499” diameter retained by studs
Round center water hole in the deck
Upside down keystone water hole in the lower
---------------
1939-40 Mercury
1939 saw several changes to V8 engines. The biggest changes were due to the introduction of the Mercury. The
Mercury had an engine based on the Ford V8, but with a noticeable increase in torque and a nice bump in
horsepower. The additional power came as the result of additional displacement, 239 cubic inches instead of
Ford's 221 cubic inches. The additional cubic inches came from a 1/8 inch larger bore, to 3 3/16 inches. Now
we have the reason for 24 studs per head. The lower line of studs on the 21 stud motors is too close to the bore
for safe production of 239 cubic inch motors. With the addition of more power came larger main and rod
bearings, this time 2.500 inch diameter mains and 2.140 inch diameter rods. Another difference started with
1939 motors is a longer crankshaft. Ford and Mercury mounted the engine fan on the end of the crankshaft in
1939, 1940, and 1941. To allow the fan to be held onto the snout of the crankshaft, the snout was made longer.
Starting in 1939 some V8 blocks were relieved between the valves and the bore at the factory. This was done to
reduce compression and detonation problems on large trucks. Both 3 1/16 bore and 3 3/16 bore blocks may be
factory relieved. All blocks still have four freeze plugs in the oil pan rails. Mercury blocks have round center
water holes in the decks that can be used to identify a 239 motor from the smaller Ford motors of the same
years.
The 239 cubic inch Mercury engine was also optional in trucks. The water holes in the deck feature a circular
center instead of the upside-down keystone. Some 239 blocks had 99 stamped into the passenger side intake rail
near the front, but not all. As with the LB, an unscrupulous person could have added this marking to a less
desirable engine also. The determination on one of these blocks should be made using the center water holes in
the deck. Mercury motors will have an upside-down keystone at the bottom and a circular hole in the middle.
These can be seen in the The 239 cubic inch Mercury engine was also optional in trucks. The water holes in the
deck feature a circular center instead of the upside-down keystone. Some 239 blocks had 99 stamped into the
passenger side intake rail near the front, but not all. As with the LB, an unscrupulous person could have added
this marking to a less desirable engine also. The determination on one of these blocks should be made using the
center water holes in the deck. Mercury motors will have an upside-down keystone at the bottom and a circular
hole in the middle.
The series engines got the 99 identification since they started in 1939 and displaced 239 cubic inches.
Features of the 1939-40 Mercury
24 studs retaining the cylinder heads
Water pumps in the block
The water drains are angled
Passes the pencil test
Core plugs in the oil pan rails
Crankcase ventilation
Insert main bearings 2.499” diameter retained by studs
Round center water hole in the deck
Upside down keystone water hole in the lower
1941-42 Mercury
Functionally the 1941 and 1942 engines are identical to the 39-40 units, but visually there are significant
changes. The most unique, and easy to see, is the intake area. The intake deck is no longer flat. This is
frequently referred to as a “raised” intake, but it isn’t. The intake surface is the same height, and the surrounding
area is lowered. Also changed is the side of the block around the exhaust ports, the block side now curve up to
meet the ports. Another change is the elimination of the core plugs in the oil pan rails. All these features are
common to both Ford and Mercury engines so final identification is made by the center water hole in the
cylinder deck.
Features of the 1941-42 Mercury
24 studs retaining the cylinder heads
Water pumps in the block
The water drains are angled
Passes the pencil test
No core plugs in the oil pan rails
Smoother block sides without raised looking exhaust ports
Crankcase ventilation
Insert main bearings 2.499” diameter retained by studs
Round center water hole in the deck
Upside down keystone water hole in the lower center of the deck.
Functionally the 1941 and 1942 engines are identical to the 39-40 units, but visually there are significant
changes. The most unique, and easy to see, is the intake area. The intake deck is no longer flat. This is
frequently referred to as a “raised” intake, but it isn’t. The intake surface is the same height, and the surrounding
area is lowered. Also changed is the side of the block around the exhaust ports, the block side now curve up to
meet the ports. Another change is the elimination of the core plugs in the oil pan rails. All these features are
common to both Ford and Mercury engines so final identification is made by the center water hole in the
cylinder deck.
Features of the 1941-42 Mercury
24 studs retaining the cylinder heads
Water pumps in the block
The water drains are angled
Passes the pencil test
No core plugs in the oil pan rails
Smoother block sides without raised looking exhaust ports
Crankcase ventilation
Insert main bearings 2.499” diameter retained by studs
Round center water hole in the deck
Upside down keystone water hole in the lower center of the deck.
rotorwrench
Well-known member
All the truck and industrial engines that I've seen were relieved. Ford was conscious about warranty so they dropped the compression. I never say never when it comes to Ford Motor Co though. They would do whatever a fleet company or a police/fire department requested as far as changes. The 99A and T blocks didn't change till 1941 when Ford was manufacturing for lend lease. The blocks didn't change again till the 59 series went into production in late 1944. The early 59 series included the 41A block as a replacement for 221s. They also had the 59 on the back.
petehoovie
Well-known member
Bored&Stroked
Well-known member
Hey Hank - how thick are the sleeves in that block? Can you knock them out and go with the resulting bore? I guess it sort of depends on what is lurking underneath them!
These things? They look like holes.
