hi sages- one of the ways i avoided getting clipped by a shyster dealership or mechanicin addition to trying to only use sl6 cars, was to try to anticipate a potentially needed repair, find out how to diagnose and repair it before i wound up on the north side of flatbush avenue at 2am sunday night with a dead car. mostly have had sl6 vehicles but this question applies to any gas engine. have replaced a few timing chains in sl6s, none broke but they would stretch, teeth would wear or break and the chain and timing would jump causing the car to no start or run like hell. unfortunately this behavior mimics other causes, bad gas, bad spark, etc. sure all of you have wrestled with that. would line up the timing marks on the balancer at tdc, pop off the dist. cap and see if the rotor pointed to #1 plug or 180 degrees out. if so chain was ok. would make sure the rotor spun without pauses. on new tanks there is no distributor, no timing marks and timing is set mysteriously by the computer or coil pack and ignition module. this is my 88 buick 3.8 v6. how would you check a timing chain malfunction on one of these bad boys? could bump theengine with my finger in #1 plug hole and feel for compression but cant locate timing mark on the balancer to reference. tip me off to the shortcut. thanks bob f

The first thing that comes to mind is to make a paint mark on the balancer for reference, then pop off a valve cover and watch a valve while rocking the balancer back and forth.

Maybe an easier way?

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