Coolant Leak [Resolved]

[Ally R]

Looking for a bit of advice as have mystery coolant leak.

66Plate T6 SWB Shuttle 150 manual

At approx 48700miles low coolant alarm went, topped up and drove home as no obvious leak.

Was due timing belt (on basis of age) and water pump anyway so got this done at 48879. Garage couldn’t find a leak.

Coolant dropped again so back into garage at 49470miles. Air Charge Cooler replaced as garage found this was cause and failed pressure test (egr also pressure tested but ok). This was an expensive job as new cooler design needing new fitting kit as per other threads.

Then at 49750 miles get another low coolant alarm needing to top up Arghhhh

Can’t see any obvious leaks. Small amount of mayo around filler cap (I’m told this is common) oil on dip looks ok.

Any thoughts? Could this be air just working it’s way out?? Temp been fine throughout. Im obviously worried about EGR cooler or head gasket.

It is very frustrating as its our only vehicle and feel we can no longer rely on it.
Thanks in advance.

 

[Paynewright]

Have you checked radiator for signs of ‘pink’ residue?

Years ago I had a coolant loss issue on my first car - Vauxhall Viva. Took me ages to find it - opened the bonnet in the dark one night and a jet of steam was coming out of a hairline crack in the rad top tank (brass). As it was at the top of the circuit no signs of coolant.

 

[Dave Mac]

Check the expansion bottle when cool to see if it’s pressurised if so you may be into a new head gasket. It’s not so common on these engines but the T5 1.9 was suspect.

 

[superquadro]

on a French forum t5zone, a person has the same symptoms as you, same engine and was told that it was the gasket after different tests, a weakness of the tdi 150?

 

[Ally R]

Just as an update on this the EGR valve and cooler assembly has now been changed as this was leaking on pressure test. Seems a bit of a coincidence that both air charge cooler and egr cooler failed at same time.

 

[Markstonee00]

I too have a 16 plate T6 SWB shuttle 150 manual and have been losing coolant. The system has never failed a pressure test and no obvious signs of any leaks. Whilst monitoring coolant levels it appeared to lose the most level after the engine had performed a regeneration cycle on the DPF operating at higher temperatures. I have replaced the water pump (shrouded), thermostat, charge cooler and only last week replaced the EGR valve and cooler assembly. Once the steel hoses were removed the flange on the EGR that should only see hot gases had a fair bit of corrosion in the bore and faces making me believe there has been water present. Fingers crossed this should be the culprit but only time will tell. If I had been advised to remove these hoses and look for any signs of corrosion before hand I may have replaced the EGR first and saved myself a couple of quid and heart ache so I hope this helps.

 

[Ally R]

Next update- still appears to be loosing coolant so will be going back to local garage again. Very frustrating as each time they say they have found leak and these items are not cheap to replace. So far have done water pump, air charge cooler and whole egr assembly.

 

[Ally R]

Photos below show how cold level change after less than 200 miles.

 

[Markstonee00]

That may be air leaving the system as it has been broken into

 

[Ally R]

I wondered that but every time I drive it it goes down a bit more. It appears to be dropping at same rate as before the did the egr valve.

I thought that all air would be purged after first 90min drive.

 

[Ally R]

So confirmed still leaking but garage still unable to find leak. EGR done, air charge cooler done.

Anyone have any thoughts? or is next step to remove the head to check gasket / cylinder head?

 

[siili]

Same issue on mine, noticed last summer, had to top up twice since then. Going to VW for annual maintenance, hope they find what's causing it.

 

[Markstonee00]

I have read on some feeds that a partially blocked heater matrix can cause the system to over pressurise. Check the expansion tanks relief hose for signs that coolant has been exhausted.

 

[Paynewright]

I have read on some feeds that a partially blocked heater matrix can cause the system to over pressurise. Check the expansion tanks relief hose for signs that coolant has been exhausted.

There is another thread about the bags of silicate in the header tank on some vans. They can burst and cause blockages. I removed the bag in my header tank.

The bag is there to maintain / boost the effectiveness of the coolant meaning it never needs changing. A moot point if the cam belt / water pump are changed every 4 years as the coolant gets replaced!

 

[Phil_j89]

If you remove the coolant bottle cap, the day after its been driven, is there still pressure in the system?

 

[Ally R]

Garage has checked everything and no obvious leaks. I spotted the bag of silicate (its intact).

Head will be coming off now and sending to specialist. Apparently local specialist has seen some with hairline cracks in the head.

Will keep you posted

 

[Dave Mac]

Garage has checked everything and no obvious leaks. I spotted the bag of silicate (its intact).

Head will be coming off now and sending to specialist. Apparently local specialist has seen some with hairline cracks in the head.

Will keep you posted

Had this on a T5 and it was obvious with head off that the gasket was leaking very slightly head was fine, good luck mate.

 

[Robert]

Garage has checked everything and no obvious leaks. I spotted the bag of silicate (its intact).

Head will be coming off now and sending to specialist. Apparently local specialist has seen some with hairline cracks in the head.

Will keep you posted

Have they done CO2 test?

 

[Ally R]

Have they done CO2 test?

Yes co2 test apparently ok.

 

[Ally R]

Update- confirmed cracked cylinder head. I have had van from new and it has never overheated and never been overloaded.

Interestingly I have been told the new head from vw is a slightly “updated” design.

Van has less than 50k on clock. Is 66 plate so out of warranty tho.