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Hi All,
I'm down to my last ounce of patience with this car. The initial "severe loss of power" problem started me off running all of the checks in the FSM. I have replaced the following: (only replaced items that did not meet FSM spec's)
AFM, FPR, coil, ECU, fuel pump and filter (blew out all lines and used in line fuel pressure guage) and the Electronic Ignition Module. When I first checked the timing, I didn't check close enough. I re-checked the timing and found that when the crank pully mark is on 0 degrees, the rotor is halfway between #1 and #4. I can get the motor to run (slightly) if I remove the distributor set screw, advance the distributor beyond the slotted adjustment area and install the set screw outside the slot. The engine has 240000 miles on it but I haven't ever heard any strange noises that would indicate chain slack. I checked the archives and most people say they have never seen an L-28 jump time. I have seen some information about cam timing for new, moderate and extremely stretched chains, would the cam timing adjustments take up enough slack/stretch that it would bring the rotor back into alignment with #1. Also, if the chain did jump one tooth, would'nt that be enough to cause the valves to hit the pistons.

Thanks for your help, this is getting the better of me...

Mike
 

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Okedokes. First off, it takes more than a one-tooth jump to bend valves. Second the distributor is fed directly off the crankshaft. Index the sucker and pull it out and look at it, you may have damage to the worm gear. The distributor has nothing to do with the timing chain. Good luck and 'bless man.
 

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I'm with Avtar...

Jumping a link one way or the other on the timing chain is what I do for tailoring the engien for the use I'm putting it to (low or high rpm usage), and tailor it from there with a Tomei adjustable gear. One link won't bend the valves. Two, maybe, depending...
Sounds more like a worn distributor busihing combined with a distributor installed wrong.
Now if it's never been apart, that's probably not the case, but a worn worm or distributor drive could cause the problems. If the bushing is badly worn, the shaft can wobble and let a worn worm skip the drive cogs on the dist shaft, but usually this is because something hit the rotor at the same time.
It's not unheard of that the outer ring of the pulley where the timing marks are has become unbonded at the dampening rubber ring, and shifted a few degrees, giving all your timing assumtions the heave ho.
I'd start by VERIFYING TDC on the engine and comparing it to the mark on the pulley.
Nothing complicated here: pull #1 plug, and stick a pencil down there after you have started the piston on the way up...
 
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