Ok
changed the following
Waterpump,thermostat,ali tower fitted,new top hose & new tank cap.


The top and bottom hose feels like its under great pressure when at running temp (guage sits half way) only a guess if its telling the truth,engine runs sweet, no coolent going into overflow tank under wheelarch now my small tube that goes from tank to tower has developed a small drip at the tower end where it changes from plastic to rubber which I will have to order yet another part...any ideas.... head gasket perhaps? surly if it was then it would push coolent into tank under wheel arch...perhaps its time to scrap it.

 

Does any one else's top/bottom hose feel fairly hard when hot, oh also fans do not kick in , I have seen them working before after a run and they don't work if I switch air con on...have checked fuses and all ok

 

The first thing is to ignore the temperature gauge as any accurate indicator of overheating. Only WhiteXKR's RealGauge or something like TorquePro will give you a correct coolant temperature reading.

I'd suspect and eliminate a sticking thermostat before looking at the more drastic possibility of a head gasket.

Did you change the water pump etc because a of cooling system fault or as preventative maintenance?

Graham

 

I changed pump,thermostat etc as I was having the same problem before, I have only refilled mostly with water as I do not want to refill with antifreeze only for it to be dumped on the floor

 

Out of curiosity, wouldn't a blown head gasket pressurise the cooling system even when the engine was cold - or is it something that usually shows/gets worse as the motor heats up?

 

When you installed the T-stat is the "weep" hole at the top (12 o-clock)? If not air pockets can form in the hose and that can cause problems.

 

yep weep hole at top,just wondering if its an air lock in rad

 

With a COLD engine, removing the Expansion Tank cap and repeatedly squeezing/releasing the top hose usually moves any trapped air.

A faulty cap can cause increased pressure by not releasing excess coolant to the Atmospheric Recovery Bottle.

Graham

 

FWIW, mine broke when i replaced the thermostat "tower". It barely took any pressure. I figured a design calling for 3 separate parts, 4 clamps and a brittle hard plastic tube as a part of the cooling system (remember, those leave you stranded when they fail!) was way too over-engineered for my taste, and I replaced this setup with a simple section of hose from the parts store. Just my take, of course. Your car, your call.

Best of luck, keep us posted.

 

managed to find some pipe to replace that stupid plastic stuff...I think I may have a big air lock as when the stat opens the bottom rad hose starts getting hot from stat back down to rad rather than the other way around so must be an air lock or blocked rad I would have thought...flush out tomorrow and see what happens

 

If the fans are not running, the cooling fan module may need replacement. This module is mounted between the fans. If it goes bad, the engine can overheat in traffic very quick. It is a computer that works off of the ECU to control the fans and their speeds. To see if you have a head gasket leaking compression into the coolant, just open the overflow cap ad watch the coolant with the engine running. If the gasket is leaking, you will see bubbles in the coolant.

 

By the way, to be sure you don't have an air lock, open the system cap and run the engine until the thermostat opens (the lower hose gets hot). This should clear any air locks. If there are air locks, you will also see bubbles in the coolant as they become cleared. Don't mistake this for a leaking head gasket.