Radiator fan constantly on?

glanzanut

glanzanut

Lifer
first of all you need to check is the car actually overheating? then if not, start tracing the wiring to see if someone has wired the fans to run constantly. using a volt meter you should be able to trace the voltage from the fans back to where the voltage is being sent:freddy:
 
S

southwalesgt

Member +
Has it been wired into a switch on the dashboard? Constant feed from battery to fan? Its usual for this to be done so that the fan comes on with ignition if its suffered from heat issues in the past or the previous owner wanted it cooler all the time.

Could be thermostat related. Have you taken thermostat out and checked its operating properly? Fuses?
 
Craig

Craig

Lifer
Has the AC been removed? If yes, you need to bridge a connection on the old AC plug to stop the fun running constantly.
 
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Dutchstarletdriver

Member +
It has happend after the headgasket failure. fixed it now its not getting hot anymore.
but the fan still goes as a mofo :S
new hg in place they replaced a new connector (green on the thermostat housing)

ps never had an AC.
Converted EP81 xli to EP82 :rockon:
 
JasonGlanza

JasonGlanza

Lifer
its the fan switch i think that they changed, could it be a faulty one and is always on as its a thermostat type switch that opens/close with variant in temperature and swithces on/off the fan!
 
weeJohn

weeJohn

Lifer
Dutchstarletdriver said:
It has happend after the headgasket failure. fixed it now its not getting hot anymore.
but the fan still goes as a mofo :S
new hg in place they replaced a new connector (green on the thermostat housing)

ps never had an AC.
Converted EP81 xli to EP82 :rockon:
Click to expand...

The switch for the fan is at the back of the thermostat housing, pointing towards the bulkhead. If the plug is off the sensor it makes the fan run all the time.

First conversion I did I had a problem like this as the switch was open when cold but the origonal wiring circuit was for a closed when cold switch.

I had to swap over sensors from the old engine, but it depends what way your wiring is.
 
thechomper

thechomper

Member +
i also had a problem were i threaded the bolt on the thermo housing and i then used a shorter bolt ,this made the fan run consent as the shorter bolts were not touching the block and the thermo housing was not getting earthed of the block ,sounds like you have already got the fan switch replaced so that rules that out anyway
 
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weeJohn

weeJohn

Lifer
Dutchstarletdriver said:
Is this one in the fusebox under the hood?
Click to expand...

Usually, pull it out and see if the fan stops, that should be the relay for it then.

The contacts are paired opposite to each other. A multi meter across each pair should show no resistance between 2 and a small resistance (probably under 100 Ohm) between the other 2.

If both sets are reading a resistance of under 100 Ohm then its burnt closed.
 
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craigant

Member +
Have you checked the temp sender the one with the green plug? I had the same problem as this so I just wired mine to a switch on the dash, car idles a lot better aswell as the fan running all the time would make my idle revs bog down and cause my oil light to flicker.
 
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Dutchstarletdriver

Member +
weeJohn said:
Usually, pull it out and see if the fan stops, that should be the relay for it then.

The contacts are paired opposite to each other. A multi meter across each pair should show no resistance between 2 and a small resistance (probably under 100 Ohm) between the other 2.

If both sets are reading a resistance of under 100 Ohm then its burnt closed.
Click to expand...

That little colored one, i replaced then it went back on.
The green temp sender is new.
 
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