Water temperature....problem

[Problem Child]

Driving back from Scotland yesterday the water temp gauge took almost 3 hours to reach almost normal, most of the time sitting just above cold. Admittedly it was -2c outside but this seemed to take forever. During this time the climate control wouldn't warm up either. Otherwise the car drove OK and no warning lights. Any ideas what the problem is? Car did eventually warm up when I got up to motorway speeds and CC worked then too

[goldnsx]

Thermostat, easy to change.

[Problem Child]

Thermostat, easy to change.Thanks for that...anyone got a part number?

[Kaz-kzukNA1]

Hi, Geoff.
The thermostat is 19301-P8E-A10.

I would also check the Fan Control Unit (FCU).
Just start the engine from cold and look at the radiator fan. If it starts spinning immediately while the engine is cold or randomly within 15min in this cold weather, your FCU is faulty and overcooling your engine.

Very little chance but as a pre-caution, please check the coolant level when the engine is cold.
The temperature sender unit is at the top surface of the water passage.

From your signature, it looks like we are talking about your 98 NSX-T.
If your thermostat is stuck open and if you haven’t replaced all of the coolant hoses, hose cramps, header tank, tank cap, (please check for any seepage at the radiator), etc over the last 15 years, you may want to consider replacing them at the same time as you will need to drain the coolant and bleed the air any way.

Climate control relies on the coolant temperature, the water valve position, etc to control the cabin temperature.
Therefore, if the coolant was not hot enough, water valve not controlled properly or too much air trapped in the heater core, you won’t get hot enough air through the air vent.
A/C compressor won’t engage if the evaporator temperature was below 4degC.

Kaz

[Problem Child]

Hi, Geoff.
The thermostat is 19301-P8E-A10.

I would also check the Fan Control Unit (FCU).
Just start the engine from cold and look at the radiator fan. If it starts spinning immediately while the engine is cold or randomly within 15min in this cold weather, your FCU is faulty and overcooling your engine.

Very little chance but as a pre-caution, please check the coolant level when the engine is cold.
The temperature sender unit is at the top surface of the water passage.

From your signature, it looks like we are talking about your 98 NSX-T.
If your thermostat is stuck open and if you haven’t replaced all of the coolant hoses, hose cramps, header tank, tank cap, (please check for any seepage at the radiator), etc over the last 15 years, you may want to consider replacing them at the same time as you will need to drain the coolant and bleed the air any way.

Climate control relies on the coolant temperature, the water valve position, etc to control the cabin temperature.
Therefore, if the coolant was not hot enough, water valve not controlled properly or too much air trapped in the heater core, you won’t get hot enough air through the air vent.
A/C compressor won’t engage if the evaporator temperature was below 4degC.

Kaz

Yes, its my 1998 NSXt, 3.2 manual
Thanks for the information, detailed as usual, Kaz.

Could you list all of the parts (and parts numbers) I should be looking to replace?

[flyingsniffer]

Geoff,

SoS offer a full set for $410. http://www.scienceofspeed.com/products/engine_performance_products/NSX/Honda/coolant_hose_kit/RHD/

They were on back order a month or two ago, I assume they order in from Japan.

[NSXGB]

Have a look in the blog, I'm fairly sure there is a list of all the hoses & part numbers.



Yes, its my 1998 NSXt, 3.2 manual
Thanks for the information, detailed as usual, Kaz.

Could you list all of the parts (and parts numbers) I should be looking to replace?

[Kaz-kzukNA1]

For RHD NA2 without modification, I will be using the following parts during my cooling system OH.

(Geoff, please note that this already includes the thermostat close to the bottom of the list.
Also, please double check that it is the thermostat issue and not something else.
At the moment, if you start the engine from cold and let it running without touching the TH pedal but inside the ventilated garage, it will take about 20 - 30min before the radiator fan starts operating for the first time. If the thermostat is stuck open, it will take ages to warm up the engine.
You don't want to run the engine under over cooling condition.
Unlike over heating, you could keep running the engine for hours under over cooling which is not good for the engine.)

*** Radiator ***
(Koyo Rad, V2032)
(bolts for cooling fan shroud)
(spare rubber seal from Mazda/Toyota)

*** Coolant Hose, RHD, NA2, MT ***
19103-PR7-A00 x 1
19104-PR7-A00 x 1
19107-PR7-A00 x 1
19501-PR7-000 x 1
19502-PR7-010 x 1
19506-PR7-A01 x 1
19507-PR7-A01 x 1
19518-PR7-A00 x 1
19519-PR7-A00 x 1
79721-SL0-010 x 1
79722-SL0-A00 x 1
79725-SL0-A00 x 1
79726-SL0-000 x 1
79727-SL0-A00 x 1
79728-SL0-A00 x 1
19422-PR7-A01 x 1
19423-PR7-A00 x 1
19424-PR7-A00 x 1
19522-PR7-J02 x 1
----------------------
19524-PR7-A01 x 1
19526-PR7-A00 x 1

*** Figure of ‘8’, rad drain/bleeder o-ring, aluminium gasket ***
91318-PY3-000 x 1
19012-PD2-004 x 2
90471-580-000 x 2

*** Cap, header tank, thermostat ***
19045-PR7-J24 x 1
19101-PR7-A02 x 1
19301-P8E-A10 x 1

*** coolant hose cramp ***
Some can be re-used if you know the original condition.
If not, replace them.
Not worth the risk.

19511-PR7-A01 x 12　　big one
19512-PC6-003 x 2　　　low tension, header tank
19513-PE0-003 x 12　　high tension
90661-SL0-A01 x 6　　　pre-set type
95002-4125004 x 8　　 small one
95002-70000 x 1　　　　 overflow tube

*** Honda Type-2 coolant ***
08CLA-G01-8L0 x 3

You will need about 16.2 - 16.5L minimum. NA2 is more like 16.2L minimum.
Although each container comes in 5L size, it actually holds about 5.45L so
you need extra one for bleeding process especially if you don't use special tool
for filling up the coolant.


*** lots of silicone/rubber grease + time ***


Again, please note that above list is only for RHD NA2 without modification.
The parts number, the number of each hose, number of hose cramp, etc are different for other spec such as the year model, RHD/LHD, MT/AT, aftermarket parts, etc.

If you have the aftermarket parts, removed the engine bay cover, etc, some of the parts in the above list won’t be suitable for the purpose without the extra parts/protection/process.

Kaz