Topics

Crankcase numbers


Tim Hamblen
 

I know this has been discussed quite a bit and maybe I just have missed this item. I have a crankcase stamped 5541. THe numbers are larger than the usual and of course there are only 4 digits.That area  has not been ground smooth as you might expect in a rebuild , you can still see a casting seam in that area. There asre no letters before or after the number. I'm just trying to deduce what a build year is for this crankcase.


Mike S
 

I have an early Cobra motor with crankcase # 554.  No letters before or after.
Mike S


Jim Bollman
 

Apparently not all early engines had the CC-46 with the serial number, I have one engine that does have the CC-46 but it also has the R for factory rebuild, The CC-46 is a lighter/smaller stamping, I wonder if that was added when they rebuilt a 46 engine since we have 2 examples without the R or CC-46. Maybe when they started putting CE7 on the 47 engines they decided to number the 46s that were returned.

Tim, 5541 is very late 46 since the last engine made in 1946 was 5586.


Jim...

On Aug 20, 2020, at 3:15 PM, Tim Hamblen via groups.io <flinttim@...> wrote:

I know this has been discussed quite a bit and maybe I just have missed this item. I have a crankcase stamped 5541. THe numbers are larger than the usual and of course there are only 4 digits.That area  has not been ground smooth as you might expect in a rebuild , you can still see a casting seam in that area. There asre no letters before or after the number. I'm just trying to deduce what a build year is for this crankcase.


Tim Hamblen
 

Makes sense Jim. I then have 2 early crankcases, the other is stamped 44**, (can't remember the last 2 digits). Jim as far as you know were there any structural or strength differences between the early cases and late ?


Jim Bollman
 

Lots of changes between early and real late but I will let an engine builder talk about differences in strength. Seals and how the bellhousing mounts are two big changes.


On Aug 20, 2020, at 5:26 PM, Tim Hamblen via groups.io <flinttim@...> wrote:

Makes sense Jim. I then have 2 early crankcases, the other is stamped 44**, (can't remember the last 2 digits). Jim as far as you know were there any structural or strength differences between the early cases and late ?


Butch
 

Although I've never paid any attention to crankcase numbers (I always looked at the conditions and features), there are several differences in webbing thicknesses. The early ones are very much less substantial, than later ones.

As a matter of practice, I no longer build on an early, rope seal crankcase.

Butch

On 8/20/2020 5:34 PM, Jim Bollman wrote:
Lots of changes between early and real late but I will let an engine builder talk about differences in strength. Seals and how the bellhousing mounts are two big changes.


On Aug 20, 2020, at 5:26 PM, Tim Hamblen via groups.io <flinttim@...> wrote:

Makes sense Jim. I then have 2 early crankcases, the other is stamped 44**, (can't remember the last 2 digits). Jim as far as you know were there any structural or strength differences between the early cases and late ?



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BARRY SEEL <CROSLEY19@AOL.COM>
 

I will not use the early crankcases. The oil gallery holes around the main bearing studs are too small, and most of all I hate the front rope seal. They always leak.