With my glow of the previous evening gone. Plus no others responding yet. I still feel with the drip test done as per instructions logic says the same as last night.

Read the forum archives step by step proccedure for the drip tube test and follow it as hundreds have done succesfully. If it checks out the same the second time just move the injection pump teeth.

I would hardly describe something like what seems to have occured as an error..
My best guess if it turns out to be the spline off by some teeth. Someone may have float timed the last pump in. Basically the same as you will be doing to correct the timing displacement,

If you tried to match the missing spline tooth with the original index position it could be off. The intended position of course matches up yet is wrong. For one reason or another the sprocket for the pump drive is probably off in its intended relation to the crank sprocket. Perhaps the last time someone changed the timing chain it happened. .This is still correctable by movement of the spline teeth.


Between the sprocket and the pump resides the mechanical pump advance. There have been almost no reports of its failure. I only state this because it is there. Actually it is amazing it fails so seldomly. Basically a mechanisim of springs and weights.


On 1985 and perhaps 1984 only there is a locking device that goes on the side of the pump to position the internal mechanisim. Then you just position your harmonic balancer to the recomended position and slide the pump in the centre area of your adjustment arc. You do not have to do the drip test at all either as it is automatically right on is more probable. I have not done one of those pumps yet.

If it is your type of pump you like myself might be doing it the hard way. I too have an 84 300d but have not even checked the pump timing yet. I would probably do it without the special tool if required as it is not easily available. Thats if I had to change pumps. Or if you were using an earlier replacement pump it would not have the slot anyways.

On reading your first posting over again you do have an 84. If you read the archives and find your old pump had this feature it may explain all. As of the introduction of the new pump there would be no requirement to install the timing chain sprockets in the relationship of the previous engines that required the index position guide at the factory. It then became totally irrelivant. They had no need to redo the tooling for the spline etc either as it did no harm.

Made life a little easier with the new system. There is an internal slot in the pump. You just rotate the pump shaft with the pump off the engine till you can engage the locking slot with your special tool.

Very late addition. I probed the archives and it seems you can use the riv tool to read the slots position in 1984 and 1985 injection pumps..So the updated timing changes mentioned did extend backwards to 1984 pumps from what I read in the archives. Just another nail in tha coffin for trusting the factory index position. The factory and dealers were no longer using it or had need to.