Diesel cooling system problems

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So maybe not, temperature shot up again yesterday, fluid all over the expansion tank, level way up inside, I'm pretty sure the fan is to blame as after stopping it just span around freely with no resistance. It was only replaced last year, must be another crap part.
 
Maybe damaged the fan getting it off? Should be locked on at startup, as it warms it will spin freely and then as it starts to get too hot it will lock up again.
 
Ok so still having this issue, had to be recovered again, this time to the garage where the car is now. They are a bit mystified, a sniff test showed nothing and on a test drive the temperature was fine until the end when the gauge shot up, they suspect the sensor but it's still pushing coolant out of the overflow, now if the system isn't pressurising why is it doing this, I cannot understand. Now the fan could account for any overheating or the sensor but what about this overflow? Many thanks, Gary.
 
Ok so changed thermostat and put a different fan on today, what i noticed was that at idle the heater air was either barely warm or cold but when revved suddenly warmed up. Now am I right in thinking the water pump is u/s? Cheers.
 
Ok so changed thermostat and put a different fan on today, what i noticed was that at idle the heater air was either barely warm or cold but when revved suddenly warmed up. Now am I right in thinking the water pump is u/s? Cheers.

The heater should be the first thing that gets warm. Unless you had an airlock and revving it burped it. Check the coolant level.
 
Coolant level all good, if it was a burp would it only happen once? This happpens everytime.

Before the stat opens coolant only goes around the head, block and heater. Heater should be first thing you notice that gets warm. Take the cap off and try burping the hoses see if the coolant level drops. If you have doubts about the water pump change it.
 
Hello all, I just thought I would post an update on this saga, so I replaced the water pump, however it still pushes coolant out of the cap and overflow. Keeping the coolant level only half way up the tank reduces this, it doesn't overheat apart from when going up a big hill at speed it started to but turning the blower on brought it back to normal (or the fan started working). A run of about five miles doesn't result in any coolant from the overflow but a longer run will. It seems it has to be pressurising but on the other hand it seems it can't be.
 
As Alan said , its not called an expantion tank for nothing there is a hot and cold markings on the side of tank if you have to much in there it will throw it out the top,.
 
Ok so I am pretty sure fan is ok as the valve on the front turns alright and there is resistance when it is span, however the car still overheats on hills (not always) and the heater only blows cold even though it is overheating! The blend motors are ok because the rest of the time they work fine, I have heard of a connection between overheating and the A/C being on, could this be it? Cheers.
 
Ok so I am now pretty certain this is an air lock as when overheating there was only cool air, squeezing the heater hoses resulted in warm air and a drop in engine temperature, what is the best way to bleed any air left in the system? Cheers.
 
Only had one once. I just kept pumping the hoses with the engine running and occasionally got in and revved it a bit then back out and squeeze wherever I could. Make sure that little line off the top of the rad is clear first. I had the cap off when doing it. Most times I've refilled I've got away with it.
 
Rather than start a new thread i thought it would be ok to add a new problem with a new car to this one?

Car ran fine until changing coolant.
Now overheats.
Brand new oem fan locks on cold start then loosens off but doesnt lock when overheating.
Header tank bubbles over sometimes even before it overheats if cap is off or pressurises a lot if cap on.
Stat seems to open.
Heater blows cold.
Cylinder leakdown and coolant static tests ok, dynamic coolant test eventually goes over 7 psi once it starts overheating.

Any help appreciated and sorry to go over old ground but i am stuck, cheers.

P. S. Water pump seems ok, metal impeller as well.
 
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