Boiling Temp of Disco 300Tdi

Hi Group

Does anyone know off hand the boiling temp of a Disco 300tdi circa '96. I
have fitted a hewitt industries engine protection system but I find the
engine temp warning coming in a little early.

I know toyota consider a cooling test to be a fail if they get within 10degC
of the boiling point of the cooling system so I would like to get a new
sender that would kick in at about the same level ie 10deg cel below system
boiling point.

regards
Stephen

Well, assuming your cooling system is pressurised to 14.7 psi, (1 bar) the
boiling point will be 100 degrees. For every 1 psi over what you have now,
will raise the boiling point by 1 celcius.

Alistair


"Fanie" <[email protected]> wrote in message
news:[email protected]...
> Hi Group
>
> Does anyone know off hand the boiling temp of a Disco 300tdi circa '96. I
> have fitted a hewitt industries engine protection system but I find the
> engine temp warning coming in a little early.
>
> I know toyota consider a cooling test to be a fail if they get within
> 10degC of the boiling point of the cooling system so I would like to get a
> new sender that would kick in at about the same level ie 10deg cel below
> system boiling point.
>
> regards
> Stephen
>

Ali wrote:
>
>
> "Fanie" <[email protected]> wrote in message
> news:[email protected]...
>
>>Hi Group
>>
>>Does anyone know off hand the boiling temp of a Disco 300tdi circa '96. I
>>have fitted a hewitt industries engine protection system but I find the
>>engine temp warning coming in a little early.
>>
>>I know toyota consider a cooling test to be a fail if they get within
>>10degC of the boiling point of the cooling system so I would like to get a
>>new sender that would kick in at about the same level ie 10deg cel below
>>system boiling point.
>>
>>regards
>>Stephen
>>
>
> Well, assuming your cooling system is pressurised to 14.7 psi, (1 bar) the
> boiling point will be 100 degrees. For every 1 psi over what you have now,
> will raise the boiling point by 1 celcius.
>
> Alistair >

A little expansion of Alistair's explanation may help.

At a 'normal' atmospheric pressure of 14.7 psi, (1 bar), water will boil
in the open at 100 deg C (If you live at 5000 ft the boiling point will
be somewhat lower.)

Engines run with pressurised cooling systems - typically either 7, 13 or
15 psi higher than this 14.7 psi. Using Alistair's 1 degree for each 1
psi above normal atmospheric pressure, water in a 13 psi system will
boil at about 113 deg C

Most cooling systems, however, are not filled with pure water but an
antifreeze/water mixture. This itself has an elevated boiling point
compared to pure water. A 50/50 ethylene glycol/water mixture boils at
around 106 deg C at normal pressure and at around 125 deg C with a 13
psi overpressure.

This 125 deg C figure is probably what Stephen was looking for and comes
with all the usual disclaimers as to its accuracy. Check the numbers
yourself! The 300TDi, I think, normally runs with a 15 psi pressure cap
so there is already a margin of safety in the numbers that I have quoted.

(There are many antifreeze manufacturers' sites on the internet which
carry this sort of information. This is typical:
http://www.eetcorp.com/antifreeze/antifreeze-faq.htm
Try a search including boiling point, antifreeze and pressure)

Dougal wrote:

> Ali wrote:
>
>>
>>
>> "Fanie" <[email protected]> wrote in message
>> news:[email protected]...
>>
>>> Hi Group
>>>
>>> Does anyone know off hand the boiling temp of a Disco 300tdi circa
>>> '96. I have fitted a hewitt industries engine protection system but I
>>> find the engine temp warning coming in a little early.
>>>
>>> I know toyota consider a cooling test to be a fail if they get within
>>> 10degC of the boiling point of the cooling system so I would like to
>>> get a new sender that would kick in at about the same level ie 10deg
>>> cel below system boiling point.
>>>
>>> regards
>>> Stephen
>>>
>>
>> Well, assuming your cooling system is pressurised to 14.7 psi, (1 bar)
>> the boiling point will be 100 degrees. For every 1 psi over what you
>> have now, will raise the boiling point by 1 celcius.
>>
>> Alistair >
>
>
> A little expansion of Alistair's explanation may help.
>
> At a 'normal' atmospheric pressure of 14.7 psi, (1 bar), water will boil
> in the open at 100 deg C (If you live at 5000 ft the boiling point will
> be somewhat lower.)
>
> Engines run with pressurised cooling systems - typically either 7, 13 or
> 15 psi higher than this 14.7 psi. Using Alistair's 1 degree for each 1
> psi above normal atmospheric pressure, water in a 13 psi system will
> boil at about 113 deg C
>
> Most cooling systems, however, are not filled with pure water but an
> antifreeze/water mixture. This itself has an elevated boiling point
> compared to pure water. A 50/50 ethylene glycol/water mixture boils at
> around 106 deg C at normal pressure and at around 125 deg C with a 13
> psi overpressure.
>
> This 125 deg C figure is probably what Stephen was looking for and comes
> with all the usual disclaimers as to its accuracy. Check the numbers
> yourself! The 300TDi, I think, normally runs with a 15 psi pressure cap
> so there is already a margin of safety in the numbers that I have quoted.
>
> (There are many antifreeze manufacturers' sites on the internet which
> carry this sort of information. This is typical:
> http://www.eetcorp.com/antifreeze/antifreeze-faq.htm
> Try a search including boiling point, antifreeze and pressure)

I should probably add that the safest course of action is to assume a
water only system fill. An alarm setting that assumes an antifreeze
presence will not have gone off when a water only system has already boiled.

In message <[email protected]>, Fanie
<[email protected]> writes
>Hi Group
>
>Does anyone know off hand the boiling temp of a Disco 300tdi circa '96. I
>have fitted a hewitt industries engine protection system but I find the
>engine temp warning coming in a little early.
>
>I know toyota consider a cooling test to be a fail if they get within 10degC
>of the boiling point of the cooling system so I would like to get a new
>sender that would kick in at about the same level ie 10deg cel below system
>boiling point.



Many respected TDI engine remanufacturers put heat sensitive stickers on
their engines. They will not honour under warranty anything that is
taken over 95 degrees.
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