Overheating?

[bla1n3]

Done a search on the many overheating threads but im a little confused?

Last night was driving to football training, stopped at the garage on route and about 1/2 mile down the road beeping temperature gauge and flashing light pulled over and opened the bonnet letting it cool down.. and it went back down to 90 but again when up to 120. decided to head home (2 miles) driving very slowly and then letting it cool down for 10 mins just to get home.

I know that 2 days ago i topped the coolant up to just below the Max line, so i know there was enough in there.

now the cars sat over night i have just got home from work and had a look because it was too dark last night and the level in the expansion bottle is about 15/20 mm below the Min line?

any ideas on what could be the problem?

 

[cupramillo]

Coolant leak? Checl all the coolant hoses for splits. Have you had the waterpump changed to the metal impellor one yet also?

 

[truCido]

Possible water pump knackered, or a leak like said above. Or head gasket - although saying that I dont think I've ever heard of a Mk3 cupra head gasket going before

 

[AlexGSi2000]

If your coolant level is staying the same then id put my money on the problem being the water pump.

The standard water pumps have plastic impellers, which are prone to breaking up... common problem im afraid.

Only solution is to replace it, but replace it with a pump with a metal impeller as they dont break up.

 

[cresswell22]

mine done that it ended up being the secondery water pump

 

[bla1n3]

just gone through all receipts that came with the car but nothing for water pump replacement? have found receipt for Coolant temperature sensor replaced.

no my coolant level has gone down from just under the MAX mark to about 15mm below the MIN mark

if it is the pump that has gone why would i be loosing coolant?

 

[truCido]

well for a start your coolants boiling if its hitting 110+ it'll evaporate, although you may just have a leak somewhere...

Check inside the top of your oil cap and also look down inside for creamy gunk!

 

[bla1n3]

nah just had a check no creamy gunk.

where would it evaporate to though?

 

[bla1n3]

IF it is a split in a hose/pipe is it safe to top the coolant tank up and run the engine letting it warm up and look for any visible signs of a split hose?

 

[tommy2008cupra]

yes

 

[bla1n3]

just started it up and left the coolant tank cap off, and seeing if the water was being returned once warm.. after reaching 90 degrees the water coolant level very slightly fell and then rose very slightly couldn't see if anything was was coming out of the refilling pipe. put the cap back on

gave the car a couple of revs to see how the tank level reacted ( now with cap back on) and it just rose and fell very slightly too, that's when the temperature started creeping past 90 degrees.

also no heat coming out of inside vents.

WATER PUMP ????

 

[tommy2008cupra]

very possible mate, wats the mileage?

 

[bla1n3]

its just under 63,000 miles

 

[tommy2008cupra]

has it had cambelt waterpump service? if not its overdue anyway not a cheap job unfortunately unless your very competent with a spanner

 

[bla1n3]

no mate it hasnt it had had a belt change prior to me buying but no receipt for a waterpump. gonna get it booked in for the service been quoted between 200 and 300 spot!

 

[tommy2008cupra]

they changed the cambelt but not the water pump......not good i would question why tbh and i would prob suggest to do the cambelt as you might aswell whilst your there

 

[cupramillo]

Like Tommy said, its very questionable why they only changed the cambelt and didnt bother with the water pump at the same time. Very odd, i'd definatly change the water pump for the metal impellor one asap if there are no receipts of it being done.

 

[tommy2008cupra]

i know the person who did it knew exactly what they were doing

 

[jamie_20vt]

is there a reason nobody's mentioned the thermostat, could be stuck in the closed position? must be worth a look as its only a £10 fix.

also, doesn't the coolant level rise slightly when its warmed up???

 

[bla1n3]

car went in this morning .. and had a phone call from the mechanic asking me about the coolant temperature sensor .. maybe a possibility?? i have a receipt for one which was changed on the car in 2006 .. is it a likely chance of that and would the sensor go after 3 or so years?