Hello

Anyone heard of a broken camshaft on vg30dett? Mine is running on only 5 cylinders after a big bang. The engine was blokked a short time. Checked compression and it looks not so bad. Not bad noises now. Before i take the valve covers i will ask here. Thx a lot.

I Iad a snapped Crankshaft. The made a loud bang

17 hours ago, TonyB said:

I Iad a snapped Crankshaft. The made a loud bang

Dont think so, because engine is running but only on 5 cylinders. 

Which cylinder is failing to fire? 
Personally I’d hook up compressed air to failed cylinder and rotate the crank, if operating correctly you should hear the air being ejected from the inlet and exhaust as the combustion cycle is performed. 
If only one cylinder is failing to operate then I would think the chances of this are low. 
Regardless as above is a sensible step in diagnosis. You’ve already stated compression seemed ok, what numbers where produced over all? 

Thx Stephen.

Little more faultfinding today. By dismanteling the Intake plenum water was running out of this. It was water from the  water/metanol injection. I think the one way valve is leaking a lot. Maybe the water was running in cylinders 5 and 6 on acceleration and has blocked the engine. I have checked the camshaft and the lifters. All looks fine. I have also checked the cylinders inside and the valves and the clutch housing with a snake cam. No fault to see. Tomorrow i will measure the piston height on all cylinders and mount all parts again. Hopefully the engine is running smooth again after that.

Are those numbers cold or warm? 
Quite low, I’d want at least 130psi really. Number 6 is pretty low compared to the others in the bank. 
 

Your theory seems logical. Hopefully you’ve not bent a rod. I can you having to pull the block to go much further forward tbh. I’d want to see the view with the pan and heads off.