Coolant flow direction

The Mad Hat Man said:

Read my fan fitting with piccies fred.

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Diesel Do said:

The aim is to regulate the engine temp as well as possible, to do that you need an accurate temp reading ie as close to the engine outlet as possible. It's the way all manufacturers do it. I tend not to listen to pub mechanics cos they cause lots of problems, if you were to put it in the bottom hose you'd find that most of the time it'd be fine, you'd be happy it's working, BUT one day you put extra demand on the system, the engine would boil the fan wouldn't cut in cos the water going past the switch is cool (relatively) and you screw up your engine!

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The Mad Hat Man said:

The poiint is - yu dont care what the temperature of the top hose, or the bottom hose! The important temperature is that of the coolant in the engine. Unfortunately it is not easy to measure the temperature within the engine, so the most practical answer is usually to measure the temperature of the hottest coolant as it leaves the engine. This is also usually where the thermostat is placed, not surprisingly.
As you dont want the engine coolant overheating, it is best to monitor this as soon as it leaves the engine block, so that extra cooling can be instigated at the earliest possible time.
If yu have an efficient overcooling radiator and measure the return temperature, it is conceivable that the engine coolant has gone above its maximum. Not good .

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Diesel Do said:

The aim is to regulate the engine temp as well as possible, to do that you need an accurate temp reading ie as close to the engine outlet as possible. It's the way all manufacturers do it. I tend not to listen to pub mechanics cos they cause lots of problems, if you were to put it in the bottom hose you'd find that most of the time it'd be fine, you'd be happy it's working, BUT one day you put extra demand on the system, the engine would boil the fan wouldn't cut in cos the water going past the switch is cool (relatively) and you screw up your engine!

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The Mad Hat Man said:

Plagiarism!

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Diesel Do said:

Can you do that with common sense???

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joe27979 said:

hi all, daft question....

which way does the coolant pump in a series? top to bottom of rad or vice versa?

I'm fitting a leccy fan to help with carb icing on cold days and need to work out which hose to tap into:

Temp switch hose adaptor off fleabay;
http://bit.ly/1cHyFd0

Muchos amigas and a very happy new year!

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