300 TDI Possible Coolant Smell

[toffa76]

Gurus,

About 6 weeks ago the water pump on my 300 TDI Disco had a catastrophic failure. I knew exactly when it happened as I heard a dull thud and then steam came into the cabin through the air vents. I only travelled for a couple of minutes to find a safe place to pull over. Anyway got it replaced and was told by the mechanic to watch the temperature gauge and for any power loss over the next few weeks just in case.

Two days ago I started to smell a possible coolant smell after driving whilst the engine was still running. I checked under bonnet however I couldn’t find any sign of coolant. I then realised the smell was coming from the exhaust.

I there has not been any overheating or loss of power at this stage.

As a coincidence I only just filled up with a full tank of Diesel two days ago and I am thinking it might be that I purchased a Diesel blend.

Any ideas appreciated.

[abaddonxi]

I don't think anyone blends diesel with coolant.

The bio blend that I use regularly has a distinct not diesel smell at the pump, and that fish and chips shop smell at the back.

Cheers
Simon

[langy]

Treat your car with a wash underneath and the engine block. Coolant can go anywhere, especially if it's whilst driving. After the wash, wipe down all the rubber pipes and around the new pump. If you have a white expansion tank, you can shine a torch down the top of it and mark the coolant level on the side. If you loose any, the clean pipes and engine will tell you what joint is leaking.

My bet is that the mechanic has disturbed the p-gasket behind the pump, and it's weeping down the block and onto the exhaust whilst at speed. That's why you smell coolant at the rear.

If it is that ( and there will be white stains on the passenger side of the block as a tell tale) then it is no big deal. A new gasket is $10 ish, and you only have to remove the alternator, remove the power steer and coolant pulleys and drain the block to get at the gasket. Use a decent silicone ( my choice is dow corning 732), let it skin, and torque it up as per RAVE

There are plenty of threads - search 'p-gasket' and you'll be fine.


If it eats coolant not due to a leak - then you might need a new head gasket. Sooner or later ( around 300,00k) a new gasket is a good idea.

[LandyAndy]

Have a very close look at your expansion bottle.
Its a well known fault that they split on the seem.If you have never replaced it,worth doing so.
There have been a number of TDi motors reported on here being overheated due to the bottle spliting.2 mates have had theirs fail and overheat requiring the head gasket to be done.
Andrew

[Sly]

When you look at your coolant expansion bottle, unbolt it and look at the bottom side of the molded join.Mine leaked slowly 4 days across the country and it drove me mad/stress. A wiff of coolant at 3 in the morn crossing the nulaboring can be discocerting.
The res had split along the join ( underside ) could not see it or coolant spill, only smell it.

[JohnE]

I'm with langy, mine used to do the same,
smell coolant, the p gasket was leaking, plus there was the occasional seep from the hoses, which had been replaced but were not tight enough,( not by me)





john

[toffa76]

Thanks to all the replys it was the dreaded "P gasket". Thanks again.