hello i have a sierra cosworth saff

i just fitted a rs500 intercooler so i hand to take out the radiator,
put it all in and filled up with coolant and water.
now the temp gauage is reading abit below when it used to when i am driving it,the needle sits just below the N on normal, but as soon as you stop moving and get in to town with slow moving traffic and traffic lights the needle drops right down to the bottom of the white square of the temp gauage,
the i went though town and back out on to roads at 60mph the gauge just came up alittle??

i pulled over and checked all the pipes and they were warm and could see the water returning to the header tank???

can out the next day and felt the pipes when they were cold and they defo had water in as could feel it in them. the header tank was on max ??

help me please

cheers gareth

 

Looks like a defective thermostat - stuck open.
When you start a cold engine the hose on top of the radiator should stay cold quite long.
If it slowly warming up right after the engine started the thermostat is stuck open.

 

Use a WAHLER stat if you can get one, much better.
tabetha

 

i changed the thermostat and bleed the water system, gauge worked correct when i left home and as soon as i can in to stopped traffic the gauge started to go back down slowly then the car started to steam under the bonnet!!!

i pulled over straight away and turned off and water and steam was coming out off the water tank! the cap was tight when i left so not sure how it was coming out?

i let i cool down and put some warm water in to fill it back up and got home!! help me please

 

I would say this is almost certainly because the fans are not working, guaranteed if fans have not been rewired, do they come on?

If overheating you need to be careful as this will cause severe damage to engine.

Martin