Is old fuel in gas tanks causing engine damage

[Here comes trouble]

I would like to get some input from members concerning engine damage from using the vehicle's old gasoline in the revived engines. There seems to be a commom thread in a few posts of members who revive an old Z engine after a couple years of non operation to later encounter engine damage. I refer to Mark/Wag Z and others who got an old Z running good after a couple years of non operation but quickly encounterd engine damage with the possible culprit being old gas varnish/gumming the valve train resulting in engine damage.. A wrecking yard operator has told me that the gasoline in the last few years is really foul as it ages and causes multiple engine problems if used. My 0ld Siver Z after years of faithful service now has fuel delivery problems after setting two years. I realze old gas can gum and varnish but is it now "derailing" the overhead cam valve train??????

[wheelman]

How can the gas possibly affect the valve train? If there is varnish in the gas it shouldn't get any further than the carbs/injectors and it would plug them producing a lean condition. I have a hard time believing the varnish is getting into the oil and then affecting anything else. Maybe it's funky oil and not gas.

 

The only problem I've had so far thats related to fuel delivery is a plugged filter from all the junk coming out of my tank. Of course I've drained the tank several times in order to weld a sump on it and fix pin hole leaks.

 

I'd look somewhere other than old gas for the cause of your valve train problems.

 

Wheelman

[Here comes trouble]

Cannot mis-ignited old fuel in the cylinders invade the valves and guides causing disruption of their function with gum and varnish causing the lash pads to lose their perch from the valve stems. ..check this recent thread about engine damage....http://forums.hybridz.org/showthread.php?t=102979