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distributor shaft installation problems

2K views 6 replies 3 participants last post by  astro355 
#1 ·
I used to be a member here, but inactive for quite a long time. Had to create a new account.

Anyway, here's my problem. I keep getting corrosion on the electrodes of the distributor, so I removed two screens and drilled out stripped thread for the cap screw on the back (forward) hole of the base. I have a 2001 Astro.

First I verified I was getting spark from the coil. The van was running very well before this, but I wanted to make sure that I did not have to deal with this problem down the road.

Before I removed the shaft, I marked the position of the rotor relative to the base. When I tried to reinstall it, I could not get it back into the same position. I finally learned that this is because the oil pump is driven off a key on the end of the shaft.

A neighbor came to help me install it. We removed the #1 plug (the cylinder which is on the left of the engine, towards the front of the van). We used the starter to position the crank so that pressure built up in the cylinder, then inserted the shaft so that the rotor pointed to the electrode for this cylinder. I used a new screw to replace the one on the back that had stripped out.

At first we had the shaft at the wrong orientation because the rotor was pointing to the left to the #1 plug wire, but then realized that the electrode for this wire is on the other side of the cap.

After going forward and back a tooth, we finally got the shaft into a position where the engine would catch, and got it to run but it was very rough. After a while it smoothed out, and we let it run for a minute, then shut it down.

I came back later in the day and tried to start it. It would crank well, but could not start. I'm now trying each tooth in turn to see if I can get it to start, but no luck so far.

Am I on the right track?
 
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#2 ·
You need to time it now. Once you turned over the engine, any marks you made are no good.

For future reference, when you try to reinstall a distributor, if the distributor does not go all the way into the hole, use a screwdriver to turn the oil pump shaft. Do that until the distributor seats against the flange of the intake manifold. The oil pump shaft only needs to spin, there is no special orientation involving it. That way you don't have to worry about timing the engine.
 
#3 ·
Thanks for the quick reply!

Regarding check of timing, there is no way for me to advance or retard the timing. The clamp that holds down the distributor shaft is keyed to the distributor base and does not allow any adjustment (other than picking a different gear tooth). Isn't the timing computer controlled on my van (2001)?

I thought that the first time we got it to run the computer would figure out how to set the timing and then it would start up fine after that. If there is some learning process in the computer regarding timing, is there a way to reset this so that all my fiddling around with different shaft positions (teeth) it can be unlearned?

I tried using a screwdriver to engage the oil pump from the distributor shaft port, and about had a heart attack. I thought mine was long enough, but it was not. It slipped out of my hands and down into the engine it went. I ended up gluing another screwdriver to it with superglue and fortunately I was able to retrieve it.
 
#4 ·
Got it working. Here's what you do if the distributor shaft has been removed and the correct tooth position is not known.

1. Remove #1 plug (front driver's side).
2. Remove distributor cap & coil wire (remaining wires on right side don't need to be removed). Set aside.
3. Crank engine until compression is felt in the #1 plug hole. This will achieve approximate top dead center (TDC).
4. There are two notches on the crankshaft vibration damper on the front of the engine, approximately 90 degrees from each other. Looking at the front of the engine, one will be at 3 o'clock relative to one at 12 o'clock. Using a wrench, rotate the nut on the damper clockwise until the 12 o'clock notch lines up with the "v" indicator on the block. This will be about the 1 o'clock position on the block and just barely visible from the top of the engine between the radiator and the serpentine belt. The #1 piston is now at TDC.
5. Replace the plug and wire for the #1 piston.
6. Remove the distributor base by removing the bolt attaching it to the engine block. As you remove it, notice that it rotates counterclockwise slightly due to the shape of the gear at the bottom.
7. Replace the distributor base so that the rotor is pointing to the electrode for #1 cylinder when it is all the way down. There is an indicator on the top edge of the distributor base which indicates this position. If the clamp does not lie flat against the block, the key at the end of the distributor shaft has not engaged with the oil pump; engage the starter momentarily and it should fall into place. However, doing so will bring the #1 piston from TDC. Tighten down the distributor shaft bolt.
8. Replace the cap and other wires in the correct location.

Engine should start! (did for me!!!)
 
#7 ·
jal said:
Thanks for the quick reply!

Regarding check of timing, there is no way for me to advance or retard the timing. The clamp that holds down the distributor shaft is keyed to the distributor base and does not allow any adjustment (other than picking a different gear tooth). Isn't the timing computer controlled on my van (2001)?

I thought that the first time we got it to run the computer would figure out how to set the timing and then it would start up fine after that. If there is some learning process in the computer regarding timing, is there a way to reset this so that all my fiddling around with different shaft positions (teeth) it can be unlearned?

I tried using a screwdriver to engage the oil pump from the distributor shaft port, and about had a heart attack. I thought mine was long enough, but it was not. It slipped out of my hands and down into the engine it went. I ended up gluing another screwdriver to it with superglue and fortunately I was able to retrieve it.
Sorry, I didn't notice that yours was a 2001. That stills seems like a little bit more work than is required. But at least its running good now.
 
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