akradiabra
Guest
Hello
About two months ago I bought a used Fiat Knaus motorhome (1993) based on a Ducato TD 14 with a 2500cc
diesel engine type 8140.27. The instrument cluster has provision to monitor coolant temperature (a guage) and a
critical coolant temperature warning lamp. The analogue guage reads 50-90-130 deg C and (from a manual)
the critical temperature is deemed to be 106 deg C. The guage has never worked and I thought there must
be an open circuit somewhere or a faulty sensor.
With it getting somewhat warmer it was time to investigate why it wasn't working. I've checked the guage and that
shows full scale deflection when given 0.25V wrt -ve on the centre terminal. The open circuit voltage on this centre terminal is approx 6v which is to be expected with 12v being presented accross the two quadature coils,
The critical temperature warning lamp is not blown. Both the guage and lamp are connected via polarised plugs into the wiring loom. Continuity tests show that they terminate in the engine bay in the wiring loom branch to the radiator fans in a lucar style black blug with an associated black wire which is connected to ground.
In the engine bay there is no sensor and indeed looking at the thermostat housing the most likely place a sensor
would have been fitted has been blanked off. A colleague has a diesel Mercedes sprinter van (05 reg) and that too has
no means of monitoring temperature (a guage has not even been fitted). I now have doubts as to whether a sensor
was ever factory fitted.
However, upon searching this incredibly useful website I came across this 1 pole coolant temperature
sensor;
http://www.micksgarage.co.uk/autopa...lyID=102747&MakeID=35&ModelID=1888&CarID=7788
Item code: T2203949
Car: FIAT DUCATO Panorama (290) 2.5 TD 08/1990 - 03/1994 95bhp 2500cc 8140.27
Number of Poles: 1
Thread Size: M16 x 1.5
Colour Coding: Black
which ticks all the right boxes, but has no provision for the critical temperature warning side of things.
This sensor though;
http://www.micksgarage.co.uk/proddetails.aspx?pid=607431&pk=F929E
Item code: 607431
Coolant Temperature Sensor - FIAT DUCATO Box (230L) 2.8 TDI 4x4 06/1999 - 04/2002 122bhp 2800cc 8140.43
Thread Size: M16 x 1.5
has the same thread size (M16 x 1.5), is fitted to a Fiat Ducato, albeit a later model.
Can I fit this 2 pole sensor, is it (thread insertion depth) the same physical size as the first sensor (item code T2203949),does it give a variable output together with a separate normally open pole for the waring lamp.
The image assocated with it from a Google shopping search seems to suggest that this is the case.
I should like to make use of the temperature guage and warning lamp if only because if there is one indication from
an engine that is of paramount importance it is how hot it is running, especially when climbing proposed Alpine and
Pyrennean mountain passes!
I do hope someone can advise me
About two months ago I bought a used Fiat Knaus motorhome (1993) based on a Ducato TD 14 with a 2500cc
diesel engine type 8140.27. The instrument cluster has provision to monitor coolant temperature (a guage) and a
critical coolant temperature warning lamp. The analogue guage reads 50-90-130 deg C and (from a manual)
the critical temperature is deemed to be 106 deg C. The guage has never worked and I thought there must
be an open circuit somewhere or a faulty sensor.
With it getting somewhat warmer it was time to investigate why it wasn't working. I've checked the guage and that
shows full scale deflection when given 0.25V wrt -ve on the centre terminal. The open circuit voltage on this centre terminal is approx 6v which is to be expected with 12v being presented accross the two quadature coils,
The critical temperature warning lamp is not blown. Both the guage and lamp are connected via polarised plugs into the wiring loom. Continuity tests show that they terminate in the engine bay in the wiring loom branch to the radiator fans in a lucar style black blug with an associated black wire which is connected to ground.
In the engine bay there is no sensor and indeed looking at the thermostat housing the most likely place a sensor
would have been fitted has been blanked off. A colleague has a diesel Mercedes sprinter van (05 reg) and that too has
no means of monitoring temperature (a guage has not even been fitted). I now have doubts as to whether a sensor
was ever factory fitted.
However, upon searching this incredibly useful website I came across this 1 pole coolant temperature
sensor;
http://www.micksgarage.co.uk/autopa...lyID=102747&MakeID=35&ModelID=1888&CarID=7788
Item code: T2203949
Car: FIAT DUCATO Panorama (290) 2.5 TD 08/1990 - 03/1994 95bhp 2500cc 8140.27
Number of Poles: 1
Thread Size: M16 x 1.5
Colour Coding: Black
which ticks all the right boxes, but has no provision for the critical temperature warning side of things.
This sensor though;
http://www.micksgarage.co.uk/proddetails.aspx?pid=607431&pk=F929E
Item code: 607431
Coolant Temperature Sensor - FIAT DUCATO Box (230L) 2.8 TDI 4x4 06/1999 - 04/2002 122bhp 2800cc 8140.43
Thread Size: M16 x 1.5
has the same thread size (M16 x 1.5), is fitted to a Fiat Ducato, albeit a later model.
Can I fit this 2 pole sensor, is it (thread insertion depth) the same physical size as the first sensor (item code T2203949),does it give a variable output together with a separate normally open pole for the waring lamp.
The image assocated with it from a Google shopping search seems to suggest that this is the case.
I should like to make use of the temperature guage and warning lamp if only because if there is one indication from
an engine that is of paramount importance it is how hot it is running, especially when climbing proposed Alpine and
Pyrennean mountain passes!
I do hope someone can advise me
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