How to Set Timing??

[Greg6.2]

1986 6.2
How do I check the timing, and what is the spec?
How do I adjust if needed?
Thanks!

[Greg6.2]

Anyone??

[NH2112]

The Haynes manual says to line the 2 lines up and this puts injection timing right at TDC. This may work well enough for a new engine or one with a new timing chain, but as the chain stretches on a high mileage engine injection timing will retard due to the slop. This is when you have to advance injection timing to compensate, and there's really no other way to do it accurately than with a timing set. There are 2 kinds, pulse and lumy mag. The pulse type keys off the injection pulse, which sends a vibration or shockwave through the injector line and which can be picked up by a piezoelectric clamp that fires the timing light. Since it keys off injection, on high-mileage engines with lower compression it won't be as accurate because combustion could begin any number of crankshaft degrees after injection. A lumy mag setup substitutes an adapter with a transparent "window" for a glow plug, an optical sensor that reads the flash of combustion through the window, and a magnetic pickup that senses the timing groove in the balancer. A computer then determines just where combustion starts as compared to TDC. This is generally regarded as more accurate.