Did my first trackday of the year.
(Footage from my first session at my first time at Bedford, I got a lot better but didn't take footage, I will explain).
I wanted to test out my oil cooler. It worked. I could go for about 6 or 7 flat out laps which is about 15 minutes, which is about as long as I do in any one sitting anyway.
Unfortunately, the car had other ideas.
20170120_144416 by
Fat Bear Photography, on Flickr
The car decided to overheat, luckily caught it before it was too severe, and dump it's coolant onto the track / pits.
Despite this, there was no obvious leak. There was a sh*t ton of water around the reservoir, but it was also all over the engine bay, so no obvious point of egress.
I topped it up, bled it, seemed ok for the next session.
Then my third session, it did it again. So I stopped.
I went to AKS Tuning after, we fitted a braided clutch line.
20170120_163016 by
Fat Bear Photography, on Flickr
Didn't really do much, slightly more feel which is good, but the main point is it eliminates the failure parts of the OEM clutch pipe.
We tried to find the water leak, but Alex nor I could see any obvious point of egress. Very annoying.
20170120_162300 by
Fat Bear Photography, on Flickr
After further investigation, and an 80 mile drive today, it seems fine.
I suspect a couple of things may have happened.
1) Cylinder head lift (typical on big turbo TDI's).
Oem bolts are 10.9 tensile strength, at high boost and high heat situations you lift the head off the block which allows exhaust gasses into the cooling circuit , pressurising it.
2) A weak/failing O-ring on the coolant temperature sensor.
This seems to have some amounts of coolant on the pipe past it. We think this is the only obvious point of failure as there are no splits or leaks in the system . The o-ring / CTS will be replaced when we re-build the head.
I did go to see Bobby, my tuner, today as he needed to test a known-working Lambda sensor on another car he was tuning, while I was there, we pressure tested the cooling system and there was no leaks. The pressure tester was not 100% but we got to about 17psi and nothing was coming out with engine off or running.
I've parked that issue for now and just avoid extended high speed driving.
I also fitted a new dash cluster. As I had wanted blue needles for a long time and finally got around to getting them done.
Here is my OEM cluster.
20170120_055218 by
Fat Bear Photography, on Flickr
and here's the replacement, it's from a Golf Mk6 GTD, but the needles were swapped and the SMD's on the dash cluster themselves were replaced to give the correct OEM blue type needles.
20170122_163922 by
Fat Bear Photography, on Flickr
20170122_163944 by
Fat Bear Photography, on Flickr
So not all bad news.
That's it for now. :)