81a6049-a===81a6050a
 

A couple of questions please. I have a set of heads with these no. 81A6049A and 81A6050A--Can someone tell me what engine these came off and what year? NEXT question. The customer wants to use these heads on this Canadan C59A engine that I'm building. We've all figured out that this engine is an early Merc 39-41 or early milartary engine. It's originaly a 3-3/16 bore block but will hold a pencil and block plugs in the pan rail. NOW, can I use these heads without enlarging valve pockets or will I have to enlarge them. I'm going to CC the heads. Does anyone know what these heads should cc? Thanks Walt PS- witch is right and left head? Thanks again? Walt

Re: 81a6049-a===81a6050a
 

https://www.fordbarn.com/forum/showthread.php?t=23725

Jack E/NJ

Re: 81a6049-a===81a6050a
 

From the green book: 6049 = RH side, 6050 = LH side, both for '38 - '42 90 and 100 HP Pass, comm and 122" trucks.

Hope this helps some.

Meric.

Re: 81a6049-a===81a6050a
 

Walt, I believe that your heads will have to be flycut to mate with any 59 series engine, due to the wider spaced valves. With the pencil ledge though, it would be a strange one to also have the large 59 cast into the bell. We all assume that these changes took place simultaniously but I guess anything is possible!

The original 81A had that number on the face, off to the side. The 81A heads changed from the 1938 version, adding a cast "A" to the face, and moving the 81A to the top next to the manifold beginning in 1939. Other differences are that the 1938 version has only the driver side (6050) drilled & tapped for the temp sender. (No hot water heater in '38).

During the '39 production, the 6049 was discontinued for a while due to both heads being machined identically with the water heater hole. This hole had a plug installed if no heater was installed.

I'm not sure if you'll wind up with the same cc.

If any of my info is incorrect, (working from my senile memory here) I'm sure to hear about it!

Re: 81a6049-a===81a6050a
 

The Ford Service Bulletins list the cc at 79-81 for your heads. If the block is 39-41 the valve pockets will be ok assuming a near stock cam lift.

Re: 81a6049-a===81a6050a
 

Thanks everyone for the info. Reply Ford38V8, this is a strange engine, there is no 59 on the bell housing, there is just the letter 5 about 4=5in. to the right of center on the bell. On the left head gasket surface just in front of the head is ( C59A )in raised letters. The front will hold a pencil. It's 3-3/16 bore. It has the 8BA style crank with 2 oil holes with 8BA rods but has the the full floating rod bearings. I understand the Canadan millatary use this crank setup with special thickness floating bearings. SO, I guess it's a 39-41 Merc or a millatary engine. Walt

Re: 81a6049-a===81a6050a
 

Re: 81a6049-a===81a6050a
 

All of the Canadian 39-41 Mercury tha I have seen, used the same block as the US version.

I had a C59 block years ago that had the core plugs in the pan area. The C59 was cast on the bell housing. The block had many cracks and was unusable so it was discarded.

You should flycut the heads. If you are reluctant to do this, check out the spacing by claying a set of 59A heads to determine if it is necessary. Trying to clay the 81A heads may bend a valve.

Re: 81a6049-a===81a6050a
 

Seems strange that a c59 block would have those features. Here 59 would stand for 1945 production. Maybe the C59 was a later replacement block for the earlier engine. I think you will have to clay the heads to be sure. Put the heads on loose and see if the valve raises the head.

Re: 81a6049-a===81a6050a
 

I was always under the assumption that the core plugs were only used in the early 24 stud engine blocks. 1938, 1939, and maybe 1940 to include the 81A, 99A, and 99T-6010 cylinder assy. I'm not sure about the 19A blocks in 41 whether they were the first with no core sand cleanout plugs. The 21A & 29A types starting in 42 and the 29A types continuing through wartime and had no core sand clean out holes in the pan rails.

I know the Canadian 95 HP blocks had the raised 99 on the right side of the block where the USA blocks had the 99 stamped in the top right intake deck on some. This was only on the 99 type 239 cid blocks though.

USA replacements were the 41A-6010 for the old 221 cid and many of them had the 59 on the bell. It would be interesting to know if the Windsor, Ontario blocks continued the core sand clean out holes in the pan rail longer than Ford Rouge plant did.

Kerby

Re: 81a6049-a===81a6050a
 

Quote:

Originally Posted by rotorwrench (Post 271331) I was always under the assumption that the core plugs were only used in the early 24 stud engine blocks. 1938, 1939, and maybe 1940 to include the 81A, 99A, and 99T-6010 cylinder assy. I'm not sure about the 19A blocks in 41 whether they were the first with no core sand cleanout plugs. The 21A & 29A types starting in 42 and the 29A types continuing through wartime and had no core sand clean out holes in the pan rails. I know the Canadian 95 HP blocks had the raised 99 on the right side of the block where the USA blocks had the 99 stamped in the top right intake deck on some. This was only on the 99 type 239 cid blocks though.

Kerby, What you advise is pretty much what I have found through my research. The core plugs were discontinued (US at least) around August of 1940. This coincided with the introduction of the "raised intake planes".

Re: 81a6049-a===81a6050a
 

I know they used those 81A heads on the early 239 cid engines until heads were finally produced for the 239s. I think many were the ones with the big A in the middle in early 1939. The old 38/41 parts book show the 99T heads were used on 09A and 19A plus 95 HP trucks. The old heads would work on those early 239 engines with no valve mods. I don't know about the Canadian stuff well enough to say on them. The valve angles were changed to clear the bigger bores better but I'm not sure exactly when that was started. 59A types in 1945 were changed but I don't know about wartime or Canadian. Not enough information yet on those.

Kerby

Re: 81a6049-a===81a6050a
 

Where are the part numbers on these heads? If the part numbers are on the back of the head facing the intake and there is an A on the top surface the heads are 39-42. If the part numbers are on the top surface the heads are 1938 (I would love to purchase a NOS set of these).

Re: 81a6049-a===81a6050a
 

The no. in the middle of the head facing you, cast in. Walt