Rover 25 1.4 2004 hot engine and radiator fan problem

Hi. Do you own an infrared thermometer? This is a great tool to have for this type of failure. Keep in mind that one of your new parts may be defective. Just because its new, doesn't mean its ok. Before you started replacing parts. How was the antifreeze? Was there any rust? Coolant should be flushed every 3-5 yrs. if not, passage ways can become restricted or clogged. Now a flush isn't good enough and the engine needs to be chemically descaled. How is the cabin heat (is the heater core working well)? If your engine runs cooler at night and the ambient temperature does affect your engine. I would start by looking at the A/C condenser. Is there something preventing air flow? You can feel and squeeze hoses. You are feeling for thin wall thickness. Hoses can fail internally, collapse and cause a restrictions. With an infrared thermometer you can point at different areas of the engine block, heads, and related cooling system components. While the engine is running, monitor coolant temperatures, thermostat and fan clutch functions and circulation through the engine, heater core and radiator. Your car has a fan clutch and an electric fan. The fan clutch is for the engine cooling system. The electric fan is for the A/C. If the electric fan is coming on as designed and it isn't helping to cool the radiator. You are probably going to find that you have a circulation problem. The fan clutch is not going to operate if the radiator doesn't get hot enough. Please write back with any questions. Good Luck.

P1299 - Cylinder Head Over Temperature Protection Active Description: Indicates an engine overheat condition was detected by the cylinder head temperature (CHT) sensor. An FMEM strategy called fail-safe cooling was activated to cool the engine. Possible Causes:

• Engine cooling system concerns
• Low engine coolant level
• Base engine concerns

Diagnostic Aids: Refer to Section 1, Powertrain Control Software , for more information on the fail-safe cooling strategy and cylinder head temperature sensor. Application Key On Engine Off Key On Engine Running Continuous Memory All GO to Pinpoint Test DL .

is the engine getting up to a good operating temperature , may have a problem with the thermostat not opening or even the water pump not working , if engine not hot enough fan won't cut in

if engine over heating coolant over flow jug will boil over you will see steam.sound like you have either faulty engine coolant temperature sensor or could have faulty fans relay or fuse or pcm problem if coolant fans dont turn on.have garage with code scanner that can do a snap shot on coolant temperature sensor check see how hot coolant temperature is see if coolant temperature over 220 degrees engine getting too hot.could have faulty water or blowed head gasket check engine oil on oil dip stick look milkly you have blowed head gasket. i use infra red laser thermometor check see how hot engine is over 107 celsius engine is overheating.

the water pump is working
the problem indicates blocked radiator cores preventing full flow at high rpm
have it flow tested by an accredited radiator shop or just fit a new radiator

Hello,
Here's something that's a very common cause of overheating, and it's easy to check.

How to test the thermostat in most vehicles;
Make sure the heater is off, start the engine and let it run for 6 to 8 minutes, ( this will allow the
engine to reach, " normal operating temperature "), from the inside of the vehicle turn the heater
temperature on high and turn the fan speed on high.
1. Listen very closely for a click sound from the engine, ( most thermostats make a click when
they open )
2. Watch your temperature guage, it should begin to lower as the coolant starts to circulate.
3. Usually within a few minutes the radiator fan will kick.


What the thermostat does;
It seperates your coolant into two parts. The first part is in your engine, the second part is in your
radiator and the coolant reservior. When the coolant in the engine reaches the temperature rating
on the thermostat the thermostat opens to allow the two parts of coolant to change places. Now
the cooled coolant in the radiator and reservior flows into the engine while the heated coolant flows
from the engine into the radiator and reservior to be air cooled by the radiator fan.

I really hope this helps you.
Donnie

Hello,
Most often that is caused by a bad thermostat.

How to test the thermostat in most vehicles;

Make sure the heater is off, start the engine and let it run for 6 to 8 minutes, ( this will allow the
engine to reach, " normal operating temperature "), from the inside of the vehicle turn the heater
temperature on high and turn the fan speed on high.
1. Listen very closely for a click sound from the engine, ( most thermostats make a click when
they open )
2. Watch your temperature guage, it should begin to lower as the coolant starts to circulate.
3. Usually within a few minutes the radiator fan will kick.

What the thermostat does;

It seperates your coolant into two parts. The first part is in your engine, the second part is in your
radiator and the coolant reservior. When the coolant in the engine reaches the temperature rating
on the thermostat the thermostat opens to allow the two parts of coolant to change places. Now
the cooled coolant in the radiator and reservior flows into the engine while the heated coolant flows
from the engine into the radiator and reservior to be air cooled by the radiator fan.

I hope this helps you.

Please check that the electric cooling fan operates when the engine gets up to temperature. Quite a common fault.

OK you have done the engine side of things. If you have an electric radiator cooling fan make sure it comes on when radiator is hot, if not the fan motor is caned or the thermostat switch is faulty. Sometimes the fan motor is supplied by a fused/relayed circuit in which case these items will also need to be checked. Check that not only does the top hose from the engine to radiator get hot but that the bottom one does too. If not this would indicate a blockage perhaps in the radiator core due to sludge. If full of sludge give both ends a flush out with a high pressure hose. Like wise do the same with the bottom hose back to the pump. If the water is circulating and the radiator fan is working then the normal cooling system is working as it should. f the engine is running hot one last thing is to find the EGR valve and check that it is opening as it should. If not the combustion temperatures go very high. One indicator of a hot engine is blue/glazed spark plugs so take one out and check it for signs of hot running. If hot then look to clean the EGR valve and associated exhaust gas feeder pipe with frayed cable, cloth and and carb cleaner spray.

Pressure test the system, it sounds like head gaskets that is backing into the water jackets and not the oil ports, which is the best of the two. Have heads checked for cracks of warping.