Cooling Fab Running When At Low Speed

[Guest mcramsay]

So first run out in the marlin today, it sounds amazing and really picks up well, had a lot more grip than I was expecting, one thing I've noticed is that at speeds 40 mph and below the fannis having to cool the car, I've set it to switch on around 98 and cut out at 94, on my stack water gauge which I think reads a little higher than the ecu temp sender ( I need to plug in my laptop for exact figures) the fan is cooling as it should and temp never goes over 100.

So I don't think I have any nasty head gasket issues etc,

But obviously the inflow of air at this speed should be more than enough to cool the rad. Looking at my set up it's not ideal, I have the alloy polo rad with 60mm core, with a kenlowe twin speed fan on front which pretty much covers all the radiator surface area, also my front grille mesh is quite fine. Do I up the fan temps slightly and see if this allows things to stabilise out ? I may try a test with removing the grille mesh and see if that helps at all.

 

Just thinking about it I thought I did hear the drive belt running the alternator & water pump screech a few times this could also not be helping

[Guest Tim Norman]

You will find that the mesh is obscuring a lot of area. you could do the maths and work it out but the simpler method is to put a much more open grille. I worked it out on the hood once when I put a fine mesh on. The actual area obstructed was close to 20%!

[speedtripledan]

Grill mesh caused me issues once. But opposite to you my car overheated over 50mph the mesh stalled the air flow took it out and fine.

[Grim]

What is the thermostat opening temperature? Your fan needs to come on at a temperature in excess of this. Many modern cars have stat opening temps of 98

[Guest mcramsay]

Got a few things to look at, had a quick peek at the belt and it has def been slipping so will put a bit more tension into it, need to actually see the real operating temp for the fan cut in and out aswell as I suspect this is also slightly low.

[Guest mcramsay]

Well had a look in the workshop manual, different from what I was expecting, thermostat is set at 80, which makes sense the car Heats up quite quickly to 80 and then the rise slows down, manual states fan cut in should be 92. For me that means the fan is going to be running constantly...,