Ghost_2008
05-10-2013, 07:46 PM
Hi Guys,
So here's the thing, as some of you may have seen from previous posts I have had issues with my cooling system for a while now. The issue started with a temp increase at stand still but at normal driving speed all was well, this turned out to be a leaking water pump. This was changed as was cam belts etc at Eurospec, however during the journey to finding out what was wrong I also changed the thermostat and rad cap, both replacement items bought at Euro Car Parts. After the initial work all seemed well, until I drove the car virtually all day, the coolant level had dropped and the temp rose once again.
When I got home I drained down the system and replaced the coolant. At no point has the car stopped working because of this nor has the temperature reach catastrophic level.
I have not found any leaks, I recently had the car on the ramp for an MOT and both myself and the tester looked under the car for any possible signs, nothing what so ever, except for what looked like coolant coming from the overflow pipe connected to coolant reservoir.
Following this, I was checking the pipes etc and I noticed that if I squeeze the top rad pipe gently I can hear the water flow into the reservoir......
Now surely if the cooling system is meant to be pressurised in order to prevent the coolant from boiling I should not be able to gently move water past the rad cap?
I therefore purchased a Rali art cap from Japan, that arrived today... I fitted it and the same occurs.... water can easily move past the rad cap into the overflow...... I would assume that this would allow the coolant in the system to boil at a lower temperature, causing the coolant to expand and simply fill the reservoir and exit through the overflow?
Hence the drop in coolant level...... As above this is not happening during short journeys or journeys where I am not hitting high speeds......
I have regularly checked the engine oil and that is absolutely fine, there is no crap in the coolant again this seems clean and clear....
So I took one of the rubber seals off the "old" rad cap and fitted this to the new rad cap, this now makes a seal and the water does not easily move past the cap and into the reservoir..... I took the car for a short drive and the reservoir filled as it should but I did notice that the top rad pipe was a little swollen...... the temperature reading on the dash was perfect, 2 or 3 notches below half way and it stayed that way, there was no lose in coolant.......
1. Is my understanding of the rad cap correct, or could anyone take a quick look at there's, squeeze the top rad pipe and see/hear if coolant can move freely into the reservoir.
2. Could the swollen pipe simply be due to the new rad cap holding pressure at 1.3 bar instead of the standard 0.9 bar?
Any assistance would be great....
Cheers
Adam
So here's the thing, as some of you may have seen from previous posts I have had issues with my cooling system for a while now. The issue started with a temp increase at stand still but at normal driving speed all was well, this turned out to be a leaking water pump. This was changed as was cam belts etc at Eurospec, however during the journey to finding out what was wrong I also changed the thermostat and rad cap, both replacement items bought at Euro Car Parts. After the initial work all seemed well, until I drove the car virtually all day, the coolant level had dropped and the temp rose once again.
When I got home I drained down the system and replaced the coolant. At no point has the car stopped working because of this nor has the temperature reach catastrophic level.
I have not found any leaks, I recently had the car on the ramp for an MOT and both myself and the tester looked under the car for any possible signs, nothing what so ever, except for what looked like coolant coming from the overflow pipe connected to coolant reservoir.
Following this, I was checking the pipes etc and I noticed that if I squeeze the top rad pipe gently I can hear the water flow into the reservoir......
Now surely if the cooling system is meant to be pressurised in order to prevent the coolant from boiling I should not be able to gently move water past the rad cap?
I therefore purchased a Rali art cap from Japan, that arrived today... I fitted it and the same occurs.... water can easily move past the rad cap into the overflow...... I would assume that this would allow the coolant in the system to boil at a lower temperature, causing the coolant to expand and simply fill the reservoir and exit through the overflow?
Hence the drop in coolant level...... As above this is not happening during short journeys or journeys where I am not hitting high speeds......
I have regularly checked the engine oil and that is absolutely fine, there is no crap in the coolant again this seems clean and clear....
So I took one of the rubber seals off the "old" rad cap and fitted this to the new rad cap, this now makes a seal and the water does not easily move past the cap and into the reservoir..... I took the car for a short drive and the reservoir filled as it should but I did notice that the top rad pipe was a little swollen...... the temperature reading on the dash was perfect, 2 or 3 notches below half way and it stayed that way, there was no lose in coolant.......
1. Is my understanding of the rad cap correct, or could anyone take a quick look at there's, squeeze the top rad pipe and see/hear if coolant can move freely into the reservoir.
2. Could the swollen pipe simply be due to the new rad cap holding pressure at 1.3 bar instead of the standard 0.9 bar?
Any assistance would be great....
Cheers
Adam