My 1.9TD xantia is running hot at high speed. By hot I mean 95+ when speed is maintained above 70mph.
I've changed the thermostat, flushed the rad when it was changed 8 months ago.
It doesn't overheat at tick over and the fans cut in and out as they should. It is OK in a traffic jam! Could it be a sensor or inefficient water pump?. I feel it is getting insufficient cooling at high speeds.
Any ideas?
overheating
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blueboy2001
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My thoughts would be airlock, blockage, waterpump and I'd eliminate them in that order.
Waterpumps tend to either leak or sieze rather than pump slowly though, particularly the simple design used on the Xantia. If it was siezing you'd more than likely know about it because it would affect the running of the engine as its run from the timing belt.
How does the heater perform? An airlock or blockage will often affect the heater matrix supply.
Waterpumps tend to either leak or sieze rather than pump slowly though, particularly the simple design used on the Xantia. If it was siezing you'd more than likely know about it because it would affect the running of the engine as its run from the timing belt.
How does the heater perform? An airlock or blockage will often affect the heater matrix supply.
If you have tried all the usual (logic) means to get rid of an overheating problem - then you should allways suspect the radiator itself. They are known to clogg by gunk & corrosion in the coolant - thus impacting the flow rate of the coolant.
To my experience - the radiator is a suspective engine killer on somewhat aged XU engines.
The problem tends to get more & more runaway - since there's also a chance that the flow-thru holes in the cylinder gasket then cloggs by the reduced flow.
This was the result clearly seen on a BX19D (XUD) engine, which I lately replaced the headgasket on. The gasket was clogged in 3 of the waterway thru holes - by calcium & gunk. These holes are no more than approx 6mm in dia - and supposed to be no more - to aid in heat distribution on the head.
A known possible cure may be to run the coolant with a weak acid : vinegar & water - half/half - after a radiator flush. Run the engine for a couple of weeks - then flush the system (& radiator !) again.
To my experience - the radiator is a suspective engine killer on somewhat aged XU engines.
The problem tends to get more & more runaway - since there's also a chance that the flow-thru holes in the cylinder gasket then cloggs by the reduced flow.
This was the result clearly seen on a BX19D (XUD) engine, which I lately replaced the headgasket on. The gasket was clogged in 3 of the waterway thru holes - by calcium & gunk. These holes are no more than approx 6mm in dia - and supposed to be no more - to aid in heat distribution on the head.
A known possible cure may be to run the coolant with a weak acid : vinegar & water - half/half - after a radiator flush. Run the engine for a couple of weeks - then flush the system (& radiator !) again.
Had mine flushed through with forte cooling system flush and then refilled with with antifreeze and cooling system conditioner last year but no diference. The D****** [:0]mechanic said that it was because the gauge was getting old but I dont believe that one little bit as I think he bodged jobbed my headgasket job which has started leaking oil yet again but worse than it was before[:(]
Just a little thought on this one based on bitter experience. I often mention this one but unforunately it seems to be one easily dismissed yet later found to be a cause.
You say the engine heats up after prolonged driving at speed. Let's face it, a car travelling at 75MPH (125KPH) should have a gale passing over the radiator, hence the water in it should be getting adequate cooling. This indicates a coolant circulation problem either as has been suggested, a partially blocked radiator or gasket etc, but can also (and often is) caused due to deterioration in hoses particularly on the intake side of the pump.
I lost a motor several years ago on a Toyota which seemed to instantly overheat, cracked the head and in fact got so hot it warped the head to such an extent that it jammed the overhead camshaft!! After it was rebuilt, as I was driving home, it almost repeated the dose, overheating almost instantaneously on a long shallow rise. When the motor was checked the next day, it was discovered that upon revving the engine, a hose leading <b>to</b> the pump (intake side) was collapsing when the engine was suddenly revved due to internal weakness of the fibre reinforcing. By winding a piece of brazing rod into a coil & winding it into the hose, the problem was solved.
The reason I am bringing this up now is that a guy over here with a Peugeot was having similar problems to yours and went through all the motions of component checks and eventually in desperation checked the hoses & found one hidden under the intake manifold was suspected of collapsing. Upon replacing, the problem has been solved.
Alan S
You say the engine heats up after prolonged driving at speed. Let's face it, a car travelling at 75MPH (125KPH) should have a gale passing over the radiator, hence the water in it should be getting adequate cooling. This indicates a coolant circulation problem either as has been suggested, a partially blocked radiator or gasket etc, but can also (and often is) caused due to deterioration in hoses particularly on the intake side of the pump.
I lost a motor several years ago on a Toyota which seemed to instantly overheat, cracked the head and in fact got so hot it warped the head to such an extent that it jammed the overhead camshaft!! After it was rebuilt, as I was driving home, it almost repeated the dose, overheating almost instantaneously on a long shallow rise. When the motor was checked the next day, it was discovered that upon revving the engine, a hose leading <b>to</b> the pump (intake side) was collapsing when the engine was suddenly revved due to internal weakness of the fibre reinforcing. By winding a piece of brazing rod into a coil & winding it into the hose, the problem was solved.
The reason I am bringing this up now is that a guy over here with a Peugeot was having similar problems to yours and went through all the motions of component checks and eventually in desperation checked the hoses & found one hidden under the intake manifold was suspected of collapsing. Upon replacing, the problem has been solved.
Alan S