[xk] Evolution and originality: Lucas Low-Note-Horn HF1748

XK
1

Listers,

inspired by Rogers topic dealing with the evolution of the
HF1748 horn, I disassembled two low-note horns 70063.
One was rebuild by someone: 70063D dated 1/55
the other is a NOS-Horn: 70063H dated 1/66.

For Rogers post see:
http://forums.jag-lovers.org/tv.php3?
eNrLL8q0zcxLSa1QS7StyFYrtjU0NjI1MjOwAtHGhsYQ2sgCQpuYQmlLKwDTtg4+

I found some differences:
NOS 70063H (1/66) has

  • 4 small holes on the outer rim
  • a more modern condenser which also have moved in position
  • no thread in the casing to mount the old-style condenser
    that doesn’t exist anymore

rebuild 70063D (1/55) has

  • no holes on the outer rim
  • old style condenser
  • thread in the housing to mount the condenser

Concerning originality I found that the central locking nut
is painted, whereas all other screws, nuts and washers
aren’t painted.
Furthermore the mounting bracket is painted only partially.
For details please see my photo album below.

Whereas the diaphragm of the NOS-Horn is also painted on
the underside in a color which I believe is RAL7048 (pearl
mouse grey), the underside of the rebuild horn (1/55) has
remnants of some black color.

I hope this adds some information to the limited knowledge
we have on this lucas horn.

Thomas
1958 XK150 DHC

http://www.jag-lovers.org/v.htm?1273134689--
tcj
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–

2

Thanks Thomas, and thanks for comments on variations.

My date-data is narrowing down gap, but still quite large in places, so any
more confirmed sightings would be great.

So far I have:-

70063A > C. Does not exist ??? (Lucas did not always start at no suffix,
nor A suffix)
70063D. 8 54 > 1 55
70063E. 6 56 > 8 57
70063F. 4 58 > 1258
70063G. none so far.
70063H. 1 66 (only date so far - maybe a belated run of spare parts
horns?)

70071A > C. Does not exist ??? (as above)
70071D. 8 54 > 2 55
70071E. 6 57 > 9 57
70071F. 4 58 > 6 60
70071G. none so far.

Roger Payne - XK140MC OTS; E-Type 4.2 S.1 OTS; DSV8.
Canberra.-----Original Message-----
From: owner-xk@jag-lovers.org [mailto:owner-xk@jag-lovers.org] On Behalf Of
tcj
Sent: Thursday, 6 May 2010 7:37 PM
To: xk@jag-lovers.org
Subject: [xk] Evolution and originality: Lucas Low-Note-Horn HF1748

Listers,

inspired by Rogers topic dealing with the evolution of the
HF1748 horn, I disassembled two low-note horns 70063.
One was rebuild by someone: 70063D dated 1/55
the other is a NOS-Horn: 70063H dated 1/66.

For Rogers post see:
http://forums.jag-lovers.org/tv.php3?
eNrLL8q0zcxLSa1QS7StyFYrtjU0NjI1MjOwAtHGhsYQ2sgCQpuYQmlLKwDTtg4+

I found some differences:
NOS 70063H (1/66) has

  • 4 small holes on the outer rim
  • a more modern condenser which also have moved in position
  • no thread in the casing to mount the old-style condenser
    that doesn’t exist anymore

rebuild 70063D (1/55) has

  • no holes on the outer rim
  • old style condenser
  • thread in the housing to mount the condenser

Concerning originality I found that the central locking nut
is painted, whereas all other screws, nuts and washers
aren’t painted.
Furthermore the mounting bracket is painted only partially.
For details please see my photo album below.

Whereas the diaphragm of the NOS-Horn is also painted on
the underside in a color which I believe is RAL7048 (pearl
mouse grey), the underside of the rebuild horn (1/55) has
remnants of some black color.

I hope this adds some information to the limited knowledge
we have on this lucas horn.

Thomas
1958 XK150 DHC

http://www.jag-lovers.org/v.htm?1273134689

tcj
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–