59A Block ID centre water passages.

[Phil Gillespie]

So I have a 59A Mercury/Ford engine. No markings on top of bell housing except 4 at LHS. The 59A marking is located at LHS front of block.
The centre water passages are: top: triangular, centre: round, lower: trapeziod.
This is contrary to reported for this one showing top: triangle, lower 2; round. Presume as engine is in NZ it would be a Canadian original?
Is this how it was? Inlet manifold is flat not raised. Bore is 3 3/16" fitted with a NOS set of C59A heads.Originally removed a head to check piston to head clearance with intention of head machining to gain the 50 thou piston to head clearance.
Appreciate assistance.
Phil NZ

 

[flatjack9]

Sounds like a 39 - 42 Merc engine. Have you tried the "pencil" test?

 

[G32]

Phil:

The C 59 (1945) block continued the round center water transfer port

feature as per the prewar 99 blocks. US 59s had middle and lower round ports.

Still learning about Flatheads! What fun!

Gene Tulsa

 

[Phil Gillespie]

Sounds like a 39 - 42 Merc engine. Have you tried the "pencil" test?

It does have the 59a at LHS top frony of block. Nil raised inlet port..
Fails pencil test.
Phil NZ.

 

[Phil Gillespie]

Some pics, showing:
Centre CW passage, flat surface at inlet manifold, front of engine at distributor, RHS front above pulley shows the 59a .
bell housing nil except a 4.


The head gaskets in use were the type with the round CW passages.
Would not seem correct for this block. Would this have any noticeable effect on CW temp & flow?
Thanks,
Phil NZ

 

[Phil Gillespie]

Have found these on Ebay: Vintage NOS 1946 Ford Fitzgerald Head Gasket 0472.
This is the configeration I require and is correct for my 1946 Mercury/Ford engine block
Phil NZ

 

[Ol' Ron]

Never saw a block like that. Learn sumpin every day.

 

[Phil Gillespie]

Never saw a block like that. Learn sumpin every day.

Thats the thing, always something new for sure. Would seem likely to be a Canadian casting given most of our engines for the RHD models would have came from there? As noted the NOS heads are marked C59a.
Going for your magic 50 thou piston to head clearance.
Phil NZ

 

[Mart]

Check for grub screw in the horizontal oil passage, or any other restrictive mods to the oil flow. It may have been intended for use with a remote full flow filter.

 

[JSeery]

Mart weren't the military mods in the fitting? Did any of the OEM block actually have a grub installed in the oil passage?

 

[Phil Gillespie]

Check for grub screw in the horizontal oil passage, or any other restrictive mods to the oil flow. It may have been intended for use with a remote full flow filter.

.


You mean the horizontal oil passage at top at valve gallery?
It was reported to have 70lb oil pressure after recent rebuild.
There was an oil return fitting at oil pan. Think at test run there was no oil filter in the system. Engine did not come with any oil filter fitted.
Phil NZ

 

[flatford8]

.


You mean the horizontal oil passage at top at valve gallery?
It was reported to have 70lb oil pressure after recent rebuild.
There was an oil return fitting at oil pan. Think at test run there was no oil filter in the system. Engine did not come with any oil filter fitted.
Phil NZ

It looks like it has 3 oil ports at the back of the block...... Mark
PS.... check the horizontal one for the grub screw Mart mentioned.

 

[Phil Gillespie]

It looks like it has 3 oil ports at the back of the block...... Mark
PS.... check the horizontal one for the grub screw Mart mentioned.

Ok I'm with you now thanks for that.
Phil NZ

 

[Mart]

I saw the third oil drilling so thought it may be worth asking the question. 3 ports might indicate a military heritage.

 

[JSeery]

I saw the third oil drilling so thought it may be worth asking the question. 3 ports might indicate a military heritage.

Needs to be checked for sure! I just thought all of the military conversions used the fitting to block the passage vs the grub used for the 90% filter mod.

 

[Mart]

Yeah they might do, the whole area needs inspecting carefully.

 

[Phil Gillespie]

Yeah they might do, the whole area needs inspecting carefully.

Will check for sure. The open port on the top was for a remote oil pressure sender. The port on the side was for a local oil pressure gauge and other one on top is still fitted with a plug.


Still looking for a set of correct head gaskets for this block. The correct one as found on ebay was only for 1 gasket only. So may have to settle on something close for centre water passages.
Phil NZ

 

[macdonge]

Phil: You may want to hold off on your head gasket search. I seem to recall that, after the coolant passage size & configuration was changed in later style blocks, the factory recommended using the later style gaskets in the earlier block. If memory serves, the redesign was to increase coolant residence time in the head for more even temperature gradients resulting in more efficient combustion and less chance of cracking. Using the later style gasket in the earlier block would supposedly serve to accomplish the same goals. I have an earlier version of your block (see my avatar) - a '39 Canadian Merc "keystone" block, as they were nicknamed. I'll have a look through my 'library' in the garage this afternoon to see if I can find the reference to the above guidance and update you on what I find. Cheers!

 

[macdonge]

Phil: I found a few references worth considering in regards to the selection of head gaskets.
1. The Ford “Repair Manual, Ford & Mercury V8 Engines” (for ‘37 - ‘48 engines) shows photos on (p. 36) of an old and new design gasket. The old design shows the 3 large trapezoidal centre coolant passages. The new design has the same trapezoidal upper passage, a large round middle hole and a small round lower hole.
2. Joe Abbin’s book “Ford & Mercury Flathead V-8 Identification & Rebuilders Guide” indicates (on p. 7-12) that “The gasket coolant passage designs evolved even if the block and head designs did not, since it was easier and cheaper to change the gasket and just as effective in some cases. Therefore it is advisable to use the latest available gasket designs for each generation rather than NOS where there is a difference.”
3. If you want the closest ‘match’ to your blocks passages, Edelbrock’s 7394 (e.g. Speedway part # 3257394) or Mac’s Part # 91A-6501-C/S/M may do the trick.
4. In my opinion however (particularly in light of references 1 & 2 above), the cylinder heads’ coolant passage configuration is probably the primary consideration in choosing a gasket set. For example, I’ve chosen BestGasket 511C’s to suit the round passages on my Offy heads.

Hope this helps.

Glen M.

 

[flatjack9]

Yes, I always use the later gaskets on my builds.