Cooling System Problem

[Harry W]

Hello,

 

I have the following problem:

 

Cooling system is losing fluid without any apparent leak, pressure test and block test done, no leak found, no combustion gases in the coolant.

 

According to the gauge the car is not overheating, sometimes a whole water reservoir would run dry over night (but not always, seems a bit random).

 

Thermostat and waterpump not checked but guess if they were faulty then the engine would overheat?

 

There also seems to be far too much pressure in the system, coolant is usually boiling up when releasing the pressure + level rises significantly and would stay until engine cooled down.

 

Can anyone help please? I will drive the car all the way to Spain for a holiday in 10 days time so need the beast to be reliable, thanks.

[chrispb123456]

Hi there and welcome to the site

Can we have some vehicle details please, year, model engine and code etc :angry:

[Harry W]

Hi there and welcome to the site

Can we have some vehicle details please, year, model engine and code etc :angry:

 

 

Hi there,

 

Thanks for the prompt reply, it's a Y-Reg, 1.9Tdi, Ghia, manual, 6 speed, engine code will have to wait until I come home tonight. Mileage is 107K, car is pretty clean and well looked after, bought it about 2 months ago (privatly) and a few days later the turbo went, so had to get that done too. Put some K seal into the coolant reservoir last night and gave it a proper test run on the motor way, again, no apparent overheating according to the gauge (wondering if the engine coolant sensor could be faulty), the bottom of the radiator felt far too cold. also the lower fadiator hose wasn't very hot at all (the top one was hot) and lot's of pressure in the reservoir when I carefully released the pressure cap (level rising and gushing out, then level falling well below minimum). This time there was a lot of 'foam' filling the space above the coolant level (right to the top), not sure if that could have to do with the K seal which I put in...

 

There is also a squeaky/brushy noise coming from the auxiliary belt are(got the belt and tensioner replaced only about a month ago)so was wondering about the waterpump.

 

I am not a mechanic at all but Fraudster seem to be at a loss too (after block and pressure test) and say the next step would be stripping down the engine (taking the cylinder head off at which point I am already looking at

[Harry W]

Hi there and welcome to the site

Can we have some vehicle details please, year, model engine and code etc :angry:

 

 

Hi there,

 

Thanks for the prompt reply, it's a Y-Reg, 1.9Tdi, Ghia, manual, 6 speed, engine code will have to wait until I come home tonight. Mileage is 107K, car is pretty clean and well looked after, bought it about 2 months ago (privatly) and a few days later the turbo went, so had to get that done too. Put some K seal into the coolant reservoir last night and gave it a proper test run on the motor way, again, no apparent overheating according to the gauge (wondering if the engine coolant sensor could be faulty), the bottom of the radiator felt far too cold. also the lower fadiator hose wasn't very hot at all (the top one was hot) and lot's of pressure in the reservoir when I carefully released the pressure cap (level rising and gushing out, then level falling well below minimum). This time there was a lot of 'foam' filling the space above the coolant level (right to the top), not sure if that could have to do with the K seal which I put in...

 

There is also a squeaky/brushy noise coming from the auxiliary belt are(got the belt and tensioner replaced only about a month ago)so was wondering about the waterpump.

 

I am not a mechanic at all but Fraudster seem to be at a loss too (after block and pressure test) and say the next step would be stripping down the engine (taking the cylinder head off at which point I am already looking at

[seatkid]

Unfortunately this is a common symptom associated with microcracking of the cylinder head around the valves (exhaust IIRC). Its usually caused by someone remapping/chipping their engine for higher power. There are several threads on this on the forum.

 

The water is blown out through the exhaust, and is not detectable.

 

I fear you were sold a pup by someone who knew he had a problem. (My view is reinforced by the fact your turbo also went)

Edited July 13, 2010 by seatkid

[chrispb123456]

Hi there

Would check the radiator for blockages first ,if system has been run with little or no antifreeze/coolant protection there will probably be corrosion/sediment passed into the radiator from the engine, get that checked first.

 

Early water pumps had faulty impellers, not sure on the date these were modified, have you any history of the water pump and cam belt being changed?

 

The Squeaky noise you talk about did you change the auxiliary belt and tensioner for that noise? The Alternator pulley has a clutch in it, this can either seize up or it can slip giving noise similar to a slipping belt.

[Harry W]

Hi there

Would check the radiator for blockages first ,if system has been run with little or no antifreeze/coolant protection there will probably be corrosion/sediment passed into the radiator from the engine, get that checked first.

 

Early water pumps had faulty impellers, not sure on the date these were modified, have you any history of the water pump and cam belt being changed?

 

The Squeaky noise you talk about did you change the auxiliary belt and tensioner for that noise? The Alternator pulley has a clutch in it, this can either seize up or it can slip giving noise similar to a slipping belt.

 

Hi there,

 

Thanks for the replies, the cambelt got changed about 2 years ago (no metion of the water pump), however, amongst the paper work there was also a note from an AA recovery incident with the advice to change the cambelt AFTERWARDS which surprised me a bit, no one inspected the belt so far. The auxiliary belt and tensioner got changed pretty much straight after I bought it (couple of months ago) as there was too much play and the tensioner was jumping about.

 

Will get it checked out further by the guy who fitted the turbo, thanks for your very helpful comments so far...shall keep you posted!

[jollyjo]

I too am having nightmare with my Ford Galaxy Y reg diesel, Have spent

[seatkid]

If the infamous plastic water pump impeller was failing or the radiator was blocked then the engine would overheat badly. Is it likely the temperature sensor is faulty as well? but still showing a normal temperature? - I think not.

 

:angry: Its not recommended to remove the pressure cap off any hot engine as the system is under pressure (due to thermal expansion of 7 litres of coolant) and you will get lots of very hot water gushing out suddenly with localised boiling in the head - dangerous!

 

Its normal for a Tdi to have a pretty cool bottom hose as the engine is so efficient it will only get hot when the engine runs at significant load i.e. high speeds and summer temperatures.

 

The alternator pulley has an integrated one way freewheel device to reduce vibration. If it seizes then vibration levels at the belt shoot up and you will see the tensioner shooting up and down wildly trying to maintain tension.

 

jollyjo - you need to check for an airlock - you need to remove the hose at the top of the front heater matrix (just to the left of the wiper motor). I presume they also changed the thermostat. Yours too could be a remapped engine victim.

[jollyjo]

Thank you for that I will get my husband on to that tomorrow. I was very careful when taking off the cap.

As I am new to this site I do appologise if I get things wrong.

Jollyjo

[jollyjo]

Does anyone know how to drain the cooling system and locate the thermostat as we can't seem to find a manual for the Y reg 2.0 Diesel

[Harry W]

Hi there,

 

Here is the promised update and it is not a joyfull one: The cause of the problem is a crack at the bottom of the engine block, got to cut my losses and sell for spare & parts (rather go and buy a new car than sticking in another engine...).