BKD Coolant Leak - Check before replacing head

[MADHUN]

It is common knowledge the first of the BKD engines had frequent issues with head gaskets and cracked heads and that with progressive engine production runs the issues become substantially less frequent.

I have just purchased a 2012 TDi Golf to replace the 2006 TDi Golf that has 275000 kms on the clock.

The 06 was getting to the stage that the cost to keep it on the road, given the mileage I do, exceeded the cost of ownership on the new one; the straw that broke the camels back was the turbo failing, which I replaced in order to sell.

Cut a long story short, when the shop removed the turbo they discovered the coolant flange, part number 038121132g, was completely fornicated and was leaking coolant, albeit slowly, into the exhaust presenting similar symptoms to a cracked head.

A few hundred dollars vs a few thousand.

Before you go ahead and order a head, if you believe it is cracked and leaking coolant, start on the turbo side of the engine and check this and other parts which can leak water to the exhaust, including the coolant flange above and EGR cooler valve.

[stormshark]

It is common knowledge the first of the BKD engines had frequent issues with head gaskets and cracked heads and that with progressive engine production runs the issues become substantially less frequent.

I have just purchased a 2012 TDi Golf to replace the 2006 TDi Golf that has 275000 kms on the clock.

The 06 was getting to the stage that the cost to keep it on the road, given the mileage I do, exceeded the cost of ownership on the new one; the straw that broke the camels back was the turbo failing, which I replaced in order to sell.

Cut a long story short, when the shop removed the turbo they discovered the coolant flange, part number 038121132g, was completely fornicated and was leaking coolant, albeit slowly, into the exhaust presenting similar symptoms to a cracked head.

A few hundred dollars vs a few thousand.

Before you go ahead and order a head, if you believe it is cracked and leaking coolant, start on the turbo side of the engine and check this and other parts which can leak water to the exhaust, including the coolant flange above and EGR cooler valve.

Very interesting read, i have a GT TDI that has just had its 120k service, my coolant has been slowly dropping the last 6 months and i asked the mechanic to check for leaks from the "Bottle and system" and they could not find anything and flushed and topped up system i think. They made no further suggestions,apart from continuing to check would you recommend anything else, should i be really be concerned do you think?

[MADHUN]

I take it is no longer under a factory warranty?

Depending on how long you intend keeping the car it might be cheaper to keep topping up the coolant than hunting down the leak.

If it's not getting hot and it's not in the oil and it's not plumming out the rear end on startup, personally I'd be inclined to leave it, however if it were still under warranty I'd be demanding they keep pulling it apart until they find it!

[Transporter]

The well equipped workshop would have pressure testing tool and should be able to find the leak, failing that I also use the smoke test with uv die when the cooling system is empty.

Sent from my GT-N8000 using Tapatalk 2

[MADHUN]

I'm guessing mine doesn't have the equipment to smoke test (excuse the ignorance, I've not heard of that before now) but they have every other workshop gadget known to man. Interestingly it pressure tested ok when they did it not long prior to replacing the turbo.

[Transporter]

I found this smoke tester worth every cent. The uv die in the original fluid shows up even the hardest to find leaks. To use it on the cooling system, you need to remove the coolant first, so it is the next step when you're 100% sure that there is a coolant loss and you can't find it. The pressure tester is fine in many situations and all of the pressure testers say that if the cooling system holds the pressure for 2 minutes, than it can be considered as pass (no leaks).
I found out that sometimes, despite that the cooling system passed the pressure test, there still can be/is a leak.

The advantage is that the smoke is more visible and it always raises up, where the coolant, if it leaks in the cavity somewhere, will stay there and may go undetected. If it goes in the cylinder you could take the spark plugs/glow plugs out to confirm the problem with the head gasket and so on.

[MADHUN]

Thought I might post a picture of the offending part, you can see where it has worn away over time, little wonder it was leaking!

[Transporter]

Thanks for the picture and the post of course. The info like this can save a lot of time, money and the frustration to someone.

[MADHUN]

I often wonder whether cracked heads are misdiagnosed by dealer mechanics and wind up costing unsuspecting punters a hoard of hard earned.

Transporter do you do VNT cleans or know anyone that does? I replaced the turbo on mine recently so have a VNT1749VA sitting on my workbench (aka pool table).

[Transporter]

Transporter do you do VNT cleans or know anyone that does? I replaced the turbo on mine recently so have a VNT1749VA sitting on my workbench (aka pool table).

Not really, but any turbo place in your town should be able to clean your turbo. It's not that hard to do and no balancing is needed after.

[Umai Naa!!]

Thought I might post a picture of the offending part, you can see where it has worn away over time, little wonder it was leaking!

Where did you say that outlet was located?

Is it the one on the gearbox end of the cylinder head?

Your cooling system could really use a clean-out!

[MADHUN]

Unfortunately I haven't the feintest clue, but the workshop discovered it when replacing the turbo, so all I can suggest is it's in the way to removing it.

I've tried locating an exploded diagram but no joy at this stage.

[Umai Naa!!]

Might be the one on the gearbox end of the cylinder head.

I've replaced a few before. Normally, the flange on the housing warps and spits the o-ring out.