The detonation came on pretty much all of a sudden. About a month ago perhaps.
I have already tried the "hillbilly tune up" by trickling about a pint of water down the carb while running. It didn't puff any black smoke, and did not make any difference in the pinging.
I have not yet pulled all the plugs and compared, that's a good suggesting to look for a possible clue.
I have also not compared actual TDC to the timing mark, another good suggestion. Not exactly the easiest thing to do in this truck, but will give it a go. What I will say is that when the TDC mark on the damper is at ZERO, the rotor in the distributor is still pretty much right under #1 cylinder post. I did check that.
Could it be plugged exhaust? Perhaps. The exhaust note had not changed, still rumbles. This truck has dual 2" exhaust pipes, no cross over, and some really large "big truck" mufflers. Can't imagine what would plug that up, unless some kid jammed a potato in there. I guess I can run a sewer snake up the exhaust and see what I find. Also will hold my hand over each outlet to see if they feel the same.
Just for sake of education, how exactly does one make sure the exhaust is not restricted? I know cat converters do that in time, but this truck does not have them. Do you disconnect the head pipe and hook up the outlet of a shop vac and see what comes out at the end? Never have had to do something like that before.
The engine does not get hot at all while driving it around. It gets up to temperature and pretty much just stays there. Keep in mind also, I can't put my foot on the gas at all other than to maintain a steady speed. Try to coax much acceleration from it, and it is a pinging monster.
As mentioned before, I already drained the tank bone dry and put 7 gals of fresh premium gas in. No difference, still pings. Unbelievable.
The battle continues....
thanks,
John
