VW Bora PD115 Coolant leak

[vwtom]

EDIT 26/09/06........ Garage changed the two stage thermostat, replaced the big fan (from GSF parts £75) as it was faulty. The garage said they had run it for a while and it seemd OK. Road tested it on the flat OK. I took it to my favourtie test run - Motorway/ 'A' roads and then a big hill. Guess what?....... It overheated. It's going back in the morning to see the VW Doctor who will go further with the invetigations. Shall keep you posted.


EDIT: Have booked it in for Monday. My specialist garage says that it is probably not the gasket but one of the two thermostats on the radiator, or one of the two cooling fans. They said that there would be problems on start up if it was gasket. There aren't. They also said that they have come across this before...............Shall keep you posted!

Hello,

I have a problem with my Bora. This seems to be a recurring problem with 1.9TDI engines, after trawling the interweb and finding people with similar problems, but no definitive answer. I know the 'web diagnosis' isn't the best in the world, but I shall give it a go. At least so I can point my VW specialist garage in the right direction.

The car has 115000 miles and has had all the correct service intervals done. It is a great distance car and I have travelled all around Europe/Scotland/Wales in it. But....it has been losing coolant for about 6 months now only when the engine is under more load than normal (hills, fast'ish motorway and when there are +3 on board). It sometimes needs 2 litres of water to top it up during an overheat episode. Normally the temp gauge reads 90 but goes up to 130 on overheat, which means back off or stop, at which point the 'Check Coolant Level' indicator is 'bonging' at me!

There is excessive pressure in the header tank, and coolant is being blown out of the overflow. I have changed all the VAG clips on the hoses for race spec jubilee clips (same as my track day kitcar has) and have changed the thermostat, renewed the header tamp cap, bled the system, used a water wetter (now deposited down the M5), had the cambelt changed and a brand new water pump fitted. Still it loses water. :zx11:

Any ideas? It seems like excessive pressure in the coolant system which often means...... head gasket. Please let it be something simple (and cheap!!)

Any suggestions before it gets booked in for a gasket check???

Thanks,

Tom

[vwtom]

Instead of editing, I shall post!!!

I dont' know whether to :zx11: or :biglaugh: as we have finally got to the bottom of the problem. VW Bora diesel coolant problem solved!

Having tried and replaced most of the ancillaries around the cooling system by myself (and garage), the VW Doctor guy I know pressure tested the cylinder head and found the two centre ones were down considerably. He took the head off the engine and found that the head gasket had gone, not badly, but enough to put pressure into the cooling system when the engine was under load. The car would start fine, but when it heated up the problem occured. This pressure then blew the coolant out of the header/exspansion tank via the pressure release cap. This in turn meant that the engine got too hot and also the coolant level dropped v. v. badly.

So... the cylinder head is being checked / pressure tested (maybe skimmed), a new original VW gasket is being fitted, and off we go.

Shall keep you informed as to the long term.

Tom

[edreidy]

I think I might have the same problem on my bora tdi 115.

I had a crack in the rad which has now been replaced but since this was done i still seem to be losing coolant but no visibility of leak. No discolouration in oil and no performace loss from engine. Garage looked at it again last week and changed a clip on one of rad hoses, it doesnt seem to have helped. I am now thinking excess pressure in coolant system caused possibly by slight HGF?

How much is a head gasket replacement?

My cars done 156k with no problems other than a MAF replacement.

cheers

:1zhelp:

[pricey_2008]

buy a bottle of steel seal it sorted my headgasket problem