Anyone know of a gas additive that specifically removes carbon buildup on pistons and valves?

They all say they will... but...???

Have you tried pouring water down the carb? With the motor fully warmed up and at about 1500-2000 rpm, slowly pour about a pint down each primary throat. Don't rush and don't let the motor stall. Keep one hand on the throttle lever while pouring. It should take about half a minute to pour each pint. The water steam cleans the cylinders pretty well.

You can also take it up to about 100MPH to "blow the carbon out".

Joe

INSTEAD OF POURING WATER, JUST TAKE OFF YOUR AIR FILTER AND USE A SPRAY BOTTLE.

|UPDATED|8/9/2003 12:37:36 PM|/UPDATED|

Why do you think you have a carbon problem?
Steve

I've got a knocking sound tht nobody has been able to identify.

When sitting in the driver's seat, it sounds like it is in the transmission. It speeds up as the car accelerates, and it continues when you step on the clutch -- therefore, how can it be the tranny?

I thought it might be a stuck lifter or carbon on a valve.

Any ideas?

Thanks,
Jim

Hi Jim
If the knock continues when you push in the clutch,
it is probably unlikely that it is carbon or an ignition problem causing preignition,knock only happens under
engine load.
Check to see that nothing is rubbing and then look for
an exhaust leak. Header gaskets are famous for leaking.
My 78 makes a terminal sounding "knock" that goes away
when it warms up. Turns out it's an exhaust leak from an AIR (smog pump) tube that rotted off at the manifold but
expands and seals when hot!
Hope this helps!
Let me know.
Better yet,drive out to Massachusetts and I'll be happy
to look at it for you!
Steve