[DaimLan] C Spec Rear End

DaimLan
1

Speaking of late production modifications to the SP250:

I recently told by John Carey of Ipswich, Mass that a late production
modification to C spec SP250’s was the installation of a slightly modified
rear end. The pinion bearings were positioned 3/4 inch wider apart in the
housing to give a longer bearing radius to the spider gears, etc.

This was done to address weakness in the early rear end that was not sturdy
enough for the drive train. One can identify the later rear ends by looking
at the top of the rear end housing. The early rear ends had a fill plug on
the very top of the rear end in addition to the one in the middle of the
housing and the drain plug on the bottom. The late model rear ends had only
two plugs.

Can anyone confirm this? My C spec does only have two plugs, top and
middle. Anyone out there willing to crawl under the car to see if they have
a top plug?

Payton Fireman
Morgantown, West Virginia

2

Through my own experience restoring these cars for almost thirty years, it
seems that the later upgraded rear axle was fitted to most of the B spec and
all C spec cars.

In the spare parts book it is classified as “second condition axle”. The
basic differences are as follows:

EARLY AXLES
Early cases had 3 filler/drain plugs e.g. one on the top, one on the bottom
and one in the back cover. This was specified as “condition one axle” in the
parts book.

This axle also had a different pinion shaft and bearings along with smaller
crown wheel support bearings.

The spider carrier is also different having smaller diameters for the
support bearings

LATER AXLES
Later cases had two filler/drain plugs e.g. one underneath and one in the
back cover (being the filler plug).

This axle had a much stronger pinion shaft and bigger bearings along with
larger crown wheel support bearings and stronger spider gear carrier
assembly.

If you have access to an original parts catalogue and check the part number
for the first and second condition axles, you will note that the different
part numbers confirm my findings as stated above.

Another small detail (for info only) I found on the two types of axles is
that the two axle tubes that are pressed into the centre casing are “stake
welded”, to retain them. The early axles had two “stakes” and the later
ones four “stakes” to retain each tube. (Thus making them more BEEFY???)
The reason for these extra welds was to eliminate fractured welds, causing
the tubes to rotate in the centre casing, usually caused by over zealous use
of power and clutch in trying to emulate a Le Mans start! I have come
across this problem occasionally and is spotted by a huge amount of
vibration just as you are releasing the clutch and moving off from a
standstill.

Hope this is helpful to you.

David Beales.
Joint DB18 Registrar (DLOC)
(Also an ardent SP250 owner)----- Original Message -----
From: Payton Fireman onepayton@att.net
To: Daimlan @ jaglovers.org daimlan@jag-lovers.org
Sent: Monday, April 24, 2000 12:25 AM
Subject: [DaimLan] C Spec Rear End

Speaking of late production modifications to the SP250:

I recently told by John Carey of Ipswich, Mass that a late production
modification to C spec SP250’s was the installation of a slightly
modified
rear end. The pinion bearings were positioned 3/4 inch wider apart in the
housing to give a longer bearing radius to the spider gears, etc.

This was done to address weakness in the early rear end that was not
sturdy
enough for the drive train. One can identify the later rear ends by
looking
at the top of the rear end housing. The early rear ends had a fill plug
on
the very top of the rear end in addition to the one in the middle of the
housing and the drain plug on the bottom. The late model rear ends had
only
two plugs.

Can anyone confirm this? My C spec does only have two plugs, top and
middle. Anyone out there willing to crawl under the car to see if they
have
a top plug?

Payton Fireman
Morgantown, West Virginia

3

Hi Listers,

Some months ago, I was in communication with the owner of a low mileage SP
250 in Newfoundland!
He claimed it was one of the last three built and that it had power
steering and power brakes from new.
He stopped corresponding when he realised that I wasn’t a buyer and that I
was only interested in the historical accuracey and significance of his
claims, which I doubted,
Has any lister any knowledge of the existance or production of these three
cars?

Thanks,

Keith
Keith & Diane Humphreys
81-a Ngataringa Rd.,
Devonport,
North shore City, 1309,
New Zealand

5H’s Design Studio Ltd.,

Kiwi Classics

Website: www.devonport.co.nz/classic.htm

4

David and interested “Listers”,
Did you all know that the SP250 shared its
axle with a milk float? I don’t know any other details and suspect that a
milk float would have had a longer axle, but was aware (in the 1970s) that
people were obtaining milk float axles, when they had trouble with their
SP250 axles.
If I remember correctly, the SP250 axle is a Salisbury axle unit and
it would be almost inconceivable that Messrs Salisbury and Co. did not use
the same differential casing and crownwheel/pinion assembly in some of their
other axle units as well. Do any other “Listers” know any more accurate
information?

Regards,
Adrian.
---------------- ************ ----------------
Adrian H. Hanwell.
AHANWEL1@FORD.COM.
Tel 01268 402344.
---------------- ************ ---------------------Original Message-----
From: David Beales [mailto:Daimler@bealeseng.fsnet.co.uk]
Sent: 24 April 2000 02:48
To: daimlan@jag-lovers.org
Subject: Re: [DaimLan] C Spec Rear End

Through my own experience restoring these cars for almost thirty years, it
seems that the later upgraded rear axle was fitted to most of the B spec and
all C spec cars.
In the spare parts book it is classified as “second condition axle”. The
basic differences are as follows:
EARLY AXLES
Early cases had 3 filler/drain plugs e.g. one on the top, one on the bottom
and one in the back cover. This was specified as “condition one axle” in the
parts book.
This axle also had a different pinion shaft and bearings along with smaller
crown wheel support bearings.
The spider carrier is also different having smaller diameters for the
support bearings
LATER AXLES
Later cases had two filler/drain plugs e.g. one underneath and one in the
back cover (being the filler plug).
This axle had a much stronger pinion shaft and bigger bearings along with
larger crown wheel support bearings and stronger spider gear carrier
assembly.
If you have access to an original parts catalogue and check the part number
for the first and second condition axles, you will note that the different
part numbers confirm my findings as stated above.
Another small detail (for info only) I found on the two types of axles is
that the two axle tubes that are pressed into the centre casing are “stake
welded”, to retain them. The early axles had two “stakes” and the later
ones four “stakes” to retain each tube. (Thus making them more BEEFY???)
The reason for these extra welds was to eliminate fractured welds, causing
the tubes to rotate in the centre casing, usually caused by over zealous use
of power and clutch in trying to emulate a Le Mans start! I have come
across this problem occasionally and is spotted by a huge amount of
vibration just as you are releasing the clutch and moving off from a
standstill. Hope this is helpful to you. David Beales.
Joint DB18 Registrar (DLOC) (Also an ardent SP250 owner)

----- Original Message -----
From: Payton Fireman onepayton@att.net
Sent: Monday, April 24, 2000 12:25 AM
Subject: [DaimLan] C Spec Rear End

Speaking of late production modifications to the SP250:
I recently told by John Carey of Ipswich, Mass that a late production
modification to C spec SP250’s was the installation of a slightly
modified rear end.
The pinion bearings were positioned 3/4 inch wider apart in the
housing to give a longer bearing radius to the spider gears, etc.
This was done to address weakness in the early rear end that was not
sturdy enough for the drive train.
One can identify the later rear ends by looking at the top of the rear
end housing. The early rear ends had a filler plug on the very top of
the rear end in addition to the one in the middle of the housing and
the drain plug on the bottom.
The late model rear ends had only two plugs.
Can anyone confirm this? My C spec does only have two plugs, top
and middle. Anyone out there willing to crawl under the car to see if
they have a top plug? Payton Fireman, Morgantown, West Virginia.