My initial post in this category was in relation to engine pinging. Suggestions were scans( done) result O2 sensors dead. Replaced checked codes cleared and now working. Still have internal rattle/ ping under acceleration/load. Only on cyl #6. Compression 120 in #6 and #8 all others at 135-140. Leak down test done on #6 at 120psi with pressure leaking slightly from intake throttle body, removing #8 plug with larger pressure release, I can only assume with#6 at tdc there is a gasket failure between #6 and #8 causing pressure to escape through #8 and then out intake as valve is open. No noticable pressure into sump so assume piston and rings are ok. Has anyone experienced this type of thing and would a gasket failure between cyls cause per ignition type issues across cylinders?? If I remove lead from#6 under load pinging/rattle is gone.

 

A tablespoon of oil in #6 does not raise compression test quite a bit? Try KSeal before tearing down to do head gaskets? Connecting rod bearing issues may also mean you'll be making a trip to the bottom end as well.

 

Haven't tried oil in cyl to see if it raises compression. KSeal?? Is that the equivalent to chemi weld? I'm hoping only blown gasket. Engine is only 150,000km with full service history, I would hope it isn't bottom end issues. It has good solid oil pressure, no over heating problems either

 

KSeal is a cooling system sealer that is sold in lots of truck stops, etc. Does not have all the "magic fibers and ground walnut shells" like some other products. Main chemical in most of these products is "water glass" or sodium silicate. KSeal seem to be the smallest volume, so IMHO it is less likely to gunk up cooling system.

 

Better yet, do a coolant pressure test and a chemical block test. If you have a leak then you haven't gooped up your coolant system.
If both tests are good, then it is time to tear down the engine and do the inspection I noted on a sticky at the top of the section.

 

I'm not losing water and no pressure from the leak down test went into cooling system. It's purely combustion chamber cross leaking from either gasket or cracked head. I'm hoping gasket only

 

Well, time to pull the engine down.

 

Ok engine pulled down. Culprit was blown gasket between #6 and #8.
Also small leakage from water jacket into 8 from perished gasket. Heads checked for warpage and no problems so vrs kit and new head bolts due to arrive tomorrow. Then the hefty task of fitting it all back together.

 

Account for all tools, one owner found this cause of "ticking" after some work by a local shop... and have fun, sounds like a great day for Fosters or Victoria Bitter (VB)...

 

Top end rebuild complete. All new and running like a dream. Also the EBD327 scan tool works a treat. All live data and ability to clear any codes.