Overheating Espace

[siwebster]

Hi, not the normal sort of motor for discussion on here, but my dad owns a 98 Espace that is overheating after a journey of only 5-10 miles. We've replaced the heater matrixes as they were leaking anyway, the thermostat, checked the water pump which is fine, but still got the problem. Anyone got any ideas where to look next??

Cheers for your help,

Simon

[wildoliver]

Is the engine overheating or is the gauge at fault, if it's the gauge it could be the dashpod or the sender unit.

Have you flushed/changed the rad? How do you know the water pump is working? Have you tested the thermostat properly?

[siwebster]

wildoliver said:

Is the engine overheating or is the gauge at fault, if it's the gauge it could be the dashpod or the sender unit.

Have you flushed/changed the rad? How do you know the water pump is working? Have you tested the thermostat properly?

Hi, I've not done the work myself all been done professionally so far, I didn't really want to get too involved! As far as I know the radiator is fine and as the cooling system has generally been in pieces I believe it's been flushed through. Water pump has been removed and checked and is in good working order and the thermostat is brand new...


Not sure about the gauge though - how would you know if it's getting too hot if the gauge didn't work properly?

Thanks for your help

[wildoliver]

lets put it this way you need to find out if the engine is overheating or just saying it is overheating. If it is overheating it could be allsorts of things from poor coolant circulation caused by blocked waterways (unlikely) to knackered pump/rad. Or even engine settings or blown head gasket.

If it is just sender or gauge (or wiring in between) then it is less serious. But unless you find out which it is you will chase it around for ever. Sadly I can't diagnose a problem that is at the other end of the country, but any decent garage shouldn't have issues doing this. I would suspect the water pump or the temperature sender or head gasket though with the fact it gets so hot so quickly.

[siwebster]

nice one, thanks, will check all the bits you've mentioned.

Cheers

Si

[Justin S]

could still be headgasket or the head.

[siwebster]

Had a look last night, the engine is boiling over so the gauge is not the problem. I've since been told that when it was initially taken to a local garage due to a leak in the cooling system they put an 'additive' in to stop the leak. I assume this was radweld, which is just about the worst thing you can put in other than for just 'get you home' emergency purposes. My thoughts now are that the radweld has been active and filling any small holes it can, possibly blocking the cooling system somewhere. A different garage has been working on it since, but say they have flushed the system through - which i would have thought was impossible if there was a blockage. If radweld is the cause do you think it might be a new radiator?

Cheers

Si

[Daveuk9xx]

The first thing to check is the expansion tank pressure cap. If the system is not pressurising because this is not sealing it will boil very quickly, especially in slow traffic. A simple pressure test which any garage can do should confirm both this and any other leakage source. A new cap, or just the rubber gasket in it, will solve the problem for pennies. Probably cheaper just to change it actually than involve a garage. At the very least check the gasket, or O ring, by eye and see if A) it's even still in there and B) not visibly buggered.

Had a mate some years ago with a Passat that was OK on runs but boiled straight over in traffic. He spent a fortune on expensive bits that there was nothing actually wrong with before I had a look and found the 50p O ring in the cap was missing. Doh!

Also if the system is not pressurising then the rad hoses won't be getting hard to the touch when the engine is hot which is another easy thing to check.

Dave

[siwebster]

Nice one, ta, will check tonight