Coolant bubbling out of expansion bottle

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NickPalmer

Member
Posts
40
Location
birmingham
Hi hope someone can help

I have a 2004 freelander.

The car has been losing coolant from bubbling out of the expansion bottle as you can see where it has tricked down the outside of the bottle, I have also witnessed the coolant rising to the top of the bottle / cap. The rac advised to change the thermostat, which I have done and also the cap, but but still bubbles over, in have checked for air locks etc.

The car had the upgraded head gasket 4 months ago.

The pipes to seem to get quite hot and hard and the radiator doesn't get hot for quite a time, therefore the thermostat doesn't open? I did test the thermostat and it opened when I put hot water in from the single bottom inlet but not the other two, is this correct?

It's losing basically the expansion bottle worth of coolant over a 40 mile journey

Any suggestions would be much appreciated

Thanks

Nick
 
Do you have the PRT thermostat or the original type in the housing at the back of the engine?

Before the "upgraded" HG (assuming it's a MLS gasket) was fitted, were all the liners checked for correct protrusion from the block?

Was the head checked for hardness and flatness, before the work was started?

I don't recommend the MLS gasket myself, as it's too intolerant of varying liner hights.

The head must be to factory hardness, or the fire rings recede very quickly, resulting in coolant being pressurised and lost out the cap.

I've seen many MLS gaskets just slapped in to the K series, without any measurements being taken, normally resulting an a repeat failure some time later.
 
I have the prt thermostat at the front of the engine connecting the 3 pipes.

It was a mls gasket and they apparently replaced bolts, water pump and thermostat, so believe they did a good job but you never know I guess! Other that that I am not sure what they did

Is it right that the radiator doesn't get hot for a while and the bottom pipe that is connected to the thermostat takes a while to get hot and therefore does not open the thermostat

Thanks
 
It was a mls gasket and they apparently replaced bolts, water pump and thermostat, so believe they did a good job but you never know I guess! Other that that I am not sure what they did
Simply throwing new parts at a K series is pointless, unless all the correct checks and measurements are carried first, especially if the MLS gasket is being fitted.
Is it right that the radiator doesn't get hot for a while and the bottom pipe that is connected to the thermostat takes a while to get hot and therefore does not open the thermostat
The radiator only gets hot, if the engine needs cooling down.
The 1.8 engine doesn't make enough heat to ever heat the rad to any great degree anyway. The same radiator is also used in the 2.5 V6, and it only gets just over ambient temperature, so the 1.8 has no chance at warming the rad up. That was part of the problem with the original design. The thermostat opened too late, so the engine got very hot, then was rapidly cooled, by the cold coolant in the oversized rad, when the thermostat finally opened.

This is why the PRT was installed instead of the original stat. It allows coolant to circulate as the revs climb, softening the warm up curve.

Incidentally what colour is the PRT that was fitted to yours?
 
This one as on photo, I have blead the system, but reading up people mention a jiggle valve could this cause the coolant to overheat and come out of the expansion bottle?
 

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This one as on photo, I have blead the system, but reading up people mention a jiggle valve could this cause the coolant to overheat and come out of the expansion bottle?
If the thermostat is that colour, then it's incorrect for the Freelander's 1.8 K. The correct Freelander PRT thermostat is grey in colour, the part number is PEL500110. This thermostat has the coolest opening temperature and the lightest pressure relief spring, so opens and the slowest engine speed.

The neutral colour PRT is for the K series when fitted to a Rover car. This has a slightly heavier relief spring, so the engine needs to be revved higher, before the pressure relief bypass opens.
 
but reading up people mention a jiggle valve could this cause the coolant to overheat and come out of the expansion bottle?
The jiggle valve being blocked makes it difficult to bleed the air out the system.

It sounds like yours is pressurised, forcing the coolant out. Does it blow the coolant, even when not at running temperature on the gauge?
 
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The coolant only comes out when the car has been running a while, the whole of the coolant bottle drained today after going down the motorway for 25 mins and 25 mins on side roads
 
The coolant only comes out when the car has been running a while, the whole of the coolant bottle drained today after going down the motorway for 25 mins and 25 mins on side roads

I'm thinking the HG has failed again. Which means it wasn't done correctly.
 
I had the RAC chap around this morning who said no signs of the head gasket gone, thought it would have been air lock which has now worked its way out, took it for a drive down the motorway and it seemed to have bubbled over slightly and hot air stopped coming out of blowers for a while, got home and carried on bleeding both heater matrix and the other one, there still seems to be air bleeding from the heater matrix bleed screw, it is common that it takes a while to bleed all the air out? or would a failed head gasket allow air into the system?

Thanks
 
I had the RAC chap around this morning who said no signs of the head gasket gone
How did he check? Did he use HC detection dye in the coolant or a CO/ HC sniffer?
got home and carried on bleeding both heater matrix and the other one, there still seems to be air bleeding from the heater matrix bleed screw
The air must stop coming out, unless it's coming in from another source .

it is common that it takes a while to bleed all the air out?
You can get most of the air out simply by allowing it to escape from the heater and lower rail bleed screws. Once just coolant comes out, then any remaining air trapped in the system will purge as it's driven.

Is the engine stopped while you're bleeding it? And are you keeping the coolant reservoir topped up all the time too?
 
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