So I've heard plenty about the 5.9's having issues with jumping teeth. This made me think about how I could check the timing chain out without pulling the engine. Could you just pull a spark plug on each bank and turn the engine till TDC and check the location of the rotor? IE: Bring cylinder 1 to TDC and verify that the rotor is on cylinder ones point? If that wouldn't work is there another method? Pulling the valve covers?

 

best bet is to put eyes on the gears and the timing marks. i have swapped the 5.9 chain before, not a hard job, just need to clear out the front of the engine. if you have gone that far, swapping tue chain is easy. download the service manual for details on how to get it done.

 

Pull the distributor cap, and position a mirror so you can see if from the front of the truck. Turn the crank so #1 is at TDC, ONLY turn the crank clockwise to position the cylinder. Once it's there, turn the crank backwards, until you see the rotor start to move. Supposedly, about 10* of rotation is OK, more than that, and it's time for a new chain/gears.

If you are close to 100K miles on it, (or over that....) it's likely time for chain and gears in any event.

 

So I did that and its sitting pretty much dead center. I'm thinking the previous owner must have done a timing job on it when they did the cap & rotor. Also I ended up cracking a spark plug. The plug had less than 1000 miles on it. Is there something that causes that or would it just be a bad plug. NGK plugs for info.

 

bad plug.

We've had a few be dead out of the box. Most we catch on warm-up, but a couple have been fine at low RPM but failed at high RPM. Makes for a really unhappy engine.