Does anyone have information on the Temperature Sensor, Part Number
C42445, page 25$.18 of E-type V12 parts book? The sensor screws
into the left hand thermostat housing. An inquiry to all the
normal parts suppliers has turned up nothing. Also, is the sensor
shown on the service manual wiring diagram (item number?)?–
Dick Wells
St. Cloud, Florida, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
Does anyone have information on the Temperature Sensor, Part Number
C42445, page 25.18 of E-type V12 parts book? The sensor screws
into the left hand thermostat housing. An inquiry to all the
normal parts suppliers has turned up nothing. Also, is the sensor
shown on the service manual wiring diagram (item number?)?–
Dick Wells
St. Cloud, Florida, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from Dick Wells sent Fri 9 Apr 2010:
Dick
Water Temperature Transmitter item 47 in the wiring diagram.
The water temp sender is fitted in the right hand side thermostat
housing. Are you using the normal convention where left/right are
as seen from the cockpit?
My parts manual shows the sender as c34812 on page 32.60.–
The original message included these comments:
Does anyone have information on the Temperature Sensor, Part Number
C42445, page 25.18 of E-type V12 parts book? The sensor screws
into the left hand thermostat housing. An inquiry to all the
normal parts suppliers has turned up nothing. Also, is the sensor
shown on the service manual wiring diagram (item number?)?
–
Pete Grice 71 S3 2+2 1S50440
Church Lawton, Cheshire, United Kingdom
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from Pete Grice sent Fri 9 Apr 2010:
Peter,
Reference is made from the drivers seat - the left thermostat
housing is where the C42445 is located. The OTS parts manual
indicates this was used only on 74 USA/CDN models. C39885 is the
thermostat housing part number, used on engines 7S.14001 and
later. The right thermostat housing has the sensor on top, just
behind the thermostat. On the C39885 housing the tapped hold is on
the outside (left) side of the housing. It is a much larger hole
than the right sensor tap. Any and all help would be most
appreciated. I’ll check the car’s original wiring diagram. I’ve
found earlier diagrams don’t show all (like seat belt interlock
system).–
Dick Wells
St. Cloud, Florida, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from Dick Wells sent Fri 9 Apr 2010:
Dear Dick & Pete,
the c42445 lh sensor is part of the US spec emissions system. If
the other parts of the emissions control vacuum tubing/wiring are
present, then this retards the ignition whilst the engine is
warming up, so it warms up quicker and ‘‘reduces’’ emissions. See
page 99 of the tan Owners Manual. Jaguar calls it the ‘‘thermal over-
ride switch’’.
kind regards
Marek–
dogdog
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
My temperature gauge has always appeared to work normally with the
needle in the exact middle of the guage. In a few isolated
instances, it has climbed above ‘‘normal’’. Now, once the engine is
up to operating temperature, the needle is staying on the right
limit of the white strip, in other words, it appears to be running
cool. Now we all know that ‘‘ain’t’’ happening! My first thought is
the temperature sensor rather than the guage, but I can’t find it.
Obviously, I need guidance. Thanks, David Weir P.S. Mine is a six
cylinder.–
'94 VDP, '91 VDP, '71 FHC
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from Michael Frank sent Sat 11 Aug 2012:
Mine has been behaving the same way since I completed my
restoration a year ago. I just used a multimeter to measure
the resistance of the sender (between the spade tab on the
end of the sender and ground) to verify that the sender is
dead. If it is working properly, the resistance should be
several hundred ohms when cool, dropping to less than a
hundred once the coolant is up to temperature. Mine never
dropped below around 200 ohms, so the gauge never registered
much beyond the ‘‘white’’ region. I got a new one from SNG and
tested it in a saucepan of water on the range. It drops to
around 50 ohms at 100C/212F. I haven’t installed the new one
yet, but should do so in the next week or so…
Good luck,
-David–
davidxk '56 XK-140 OTS, '69 XKE OTS , '98 XK8
Monterey CA, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from davidxk sent Sat 11 Aug 2012:
70C should be about 70 ohms on the sender…–
Ray Livingston - '64 OTS Santa Cruz, CA
Santa Cruz, CA, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from David in Boerne, TX sent Sat 11 Aug 2012:
Found it. Hidden by the plug wires. At least that is my excuse.
Thanks Mike and the rest of you. David Weir–
'94 VDP, '91 VDP, '71 FHC
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
The “Tan” manual is the final version of the S3 E-type V12 Owners Handbook that came with the car. North American edition has an Emissions section.
As a follow-up on my request for information (circa 2010) regarding the temp sensor/switch, C42445, page 25.18 of E-type V12 parts book, answers came in the form of the factory drawing for the part. On the drawing, annotated were the temperature parameters of the switch. It’s an adaptation of a General Motors Emission Control system, adopted to meet Federal Emission Standards of the day!
Thank you for getting back to me Dick, I have that manual also, still in the plastic bag, guess I should open it!
You wouldn’t have the GM equivalent part number by any chance?
Unfortunately, C42445 was a pure Jaguar design. I know of no like GM sensor. None of the Jaguar manuals, to include the Tan Owners manual, offered any details regarding parameters. An acquaintance in the UK was able to obtain the factory drawing for the part, revealing opening and closing temperatures of the switch. Marek gives an excellent analysis of the switch’s operation within this blog. See DogDog2…
A new C42445 is more rare than probably a moon rock! You may be able to test your old one by heating it in water. Connect a VOM to the switch, a thermometer to note water temperature, and note if the switch opens and closes and at what temperature. Sorry I can’t offer more help than that.
The US version of the blue Owner’s Manual booklet is identical, save for the fact that it is tan (“buff”) coloured like a manilla envelope and has an extra chapter at the end listing the emissions equipment fitted for 1974. It also has an updated wiring diagram foldout page which has some of the extra equipment fitted, like the seatbelt warning system wiring. As Dick’s first post implies, the tan coloured booklet is not fully comprehensive, but you can work out how most of the extra US emissions equipment works by cross referencing it against your white 1974 Parts Manual.
Hello again Marek, I have the feeling I may be spinning my wheels working over this sender issue.
I have fitted Weber carburetors to the car, there is a vacuum takeoff at the rear of each Inlet manifold (L+R).
I have not fitted nor do I intend to refit the EX/EM components.
The holes in the cylinder heads are plugged as are the outlets in the Exhaust manifolds.
That said, I am trying to determine how best to take the Vacuum feeds from the Inlet manifolds and run them to the distributor and Brake Servo, I think that’s the only 2 feeds I need? Join them then take the feeds off that line?
Any ideas/thoughts/issues you see?