hot or not

[pieman1]

Hi I might have a problem or might just be me being paranoid took my t25 out last week (1.9 water cooled diesel) and it seemed to be running hot or hotter
than it used to. got to about 50-55 and shot up to halve way on the gauge if I slow down it starts to drop in tempter it never used to go off the white mark
on the gauge. no red lights. do I just leave it or flush out the full system and put new coolant in ...or can you lot think of any thing that might help.
needs to be right because I am going on me hols in April

[ermie571]

shouldn't sit on the white guage....should be at or around the led for petrol engines wouldn't have thought diesel would be any different

Em
x

[Red Westie]

Typically the needle should rest just a little over half way on the gauge once up to temperature and stay pretty much in the same position whilst moving. If for whatever reason you end up getting stuck in traffic the gauge may creep up to approximately 2/3rds (this may take 2-3 minutes in stationary traffic with the engine idling) at this point the thermo switch in the radiator senses higher than normal temperature and switches the electric radiator fan on for 30secs plus.. to bring the needle down to the normal (central) position again.
Yours doesn't sound right at all. infact running on the lower white line indicates the engine is running too cool, chances are the thermostat needs replacing so it correctly opens (typically between 82-86 degrees C) for speedy warm and regulates (opens and closes) to control overall coolant temperature (coolant in the engine AND the seperate body of coolant in the front to rear pipes and radiator) On a cold day the thermostat may open and close many times until the total body of coolant rises above the thermostats set opening temperature.
Thermostats are pretty cheap at under a tenner so replace it as a matter of cause.
Martin

[pieman1]

yep thanks martin will swap the thermostat anyway do you think when it was staying on the white the thermostat might of been stuck?? just a blind idea cos we used to drop the them in a cup of hot water when trying to see if they where working on
old mk1 escorts... that was about a million years ago

[Red Westie]

The proper thermostat tester looks like a sauce pan with lid and thermometer. The lid has several round holes to suit different sized thermostats. It is filled with water and slowly heated whilst the business side of the waxstat (spring side) hangs it's backside in the water. The purpose of the test is to visually SEE the point at which the stat opens then quickly look at the temperature reading on the thermometer. The temperature that it opens at should be within a couple of degrees of the stamped opening temperature (always etched somewhere on the stat)
Nowadays, these tests are very rarely done mainly because the time taken to carry out the test would cost more than the replacement it'self.

PS: Simply dumping a stat into boiling water only checks if it opens what it doesn't do is check the all important temperature at which it opens.

Nothing to do with the question I know lol.....
Martin

[pieman1]

thanks for your time mate will just get a new one.