25/04/2026
Every time you push things to the limits to find what these are is always risky, but then sometimes Lady Luck just isn’t on your side….well today was that day.
Prepare yourself for the carnage🫣🫣
Just over 500 miles of running in the new build at 8200rpm in 2nd gear going for 3rd engine cuts out instantly, throttle jams and I find myself coasting to a lucky lay-by and stop and pull the bonnet off, throttlebody wiggled off its jammed position then went to try and start the engine and what can only best be described was the sound of a ball bearing bouncing around in a tin can😩
Only tried once and immediately recovered Bella.
Further inspections found the chargers output shaft has failed shearing off resulting in the nut bouncing around inside the compressor housing which actually ricocheted into the air filter. Now at this stage my heart just fell out as I know all this damaged aluminium compressor wheel FOD had entered the chat🤔 question is how many of the cylinders injested the FOD🤦♂️
So the next step in evaluating the damage is to conduct a compression test on all 4 cylinders. 1,2 and 4 all 13bar or there about….but cylinder 3 only showing a poultry 8bar and spraying some oil down the cylinder didn’t improve the compression which means we have valve sealing interruption which leaves me to carrying out a leak down test at TDC which showed intakes absolutely pi***ng out. Now I’m thinking there’s aluminium FOD trapped in the valve seat area so it’s time to remove the head and pray there isn’t any bent valves to which I’m now thinking the aluminium FOD had melted to the intake valves and caused a micro high spot enough to allow a partial seal hence the 8bar of compression and not a typical fat diddly squat zero compression which is typical of bent valves.
Whipped the head off and found as I’d expected…molten aluminium’s has bonded to the valve seat area in both valve and seat which as caused a micro high spot. Well after a quick rough and smooth lap all molten aluminium has been removed and vacuum test back to 25inHG. Yes!!!! She’s lives again so it’s just a simple case of building her back together and sending the damaged charger off for repair.
What’s actually amazing to me is the fact when the compressor shaft failed and the nut jammed the compressor wheel that’s what actually stalled the engine out at 8200rpm. That’s how good my manual belt tensioner works on my set up as I was worried for belt slip for the rpm I’m aiming for.
And this had all been carried out in less than 24hrs before going on holiday with a VERY patient better half, break, recover, identify the fault and fix it! Well the engine anyway 😂
Anyway see you in a week!
