Distributor pull and replace questions

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Ewhitaker0020

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Hey, I'm replacing my intake manifold and had to pull my distributor. I watched a video that said if you're just pulling it and putting the exact same distributor back in I could rotate the engine until the rotor lined up with the firewall and make a mark where it sat. Then I could pull the distributor and put it back in exactly where it was and everything would line up again.

One thing I didn't expect is when I pulled the distributor the rotor spun as I pulled it out. Shouldn't I just be able to, through trial and error, keep moving the rotor and inserting the distributor until the rotor lines up with the mark I made on the firewall? It should just drop straight back into the oil pump drive right?

I've seen the method of rotating to the TDC on the compression stroke of cylinder 1 and lining the rotor up with cylinder 1 and I'm prepared to do this, but I don't have any way to set the timing of the engine myself. It was already in time before and if I get the rotor exactly where it was it'll be in time again right? The distributor itself was turned to where the wires were straight down towards the engine.
 

AuroraGirl

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What I did, was when I took the distributor out. I took a paint marker and market the base of the distributor and took the cap off and marked the internal plastic parts(the part that would rotate) let it dry, then pulled it. It turned and stuff out of it, but I just made sure to line it up as I was putting it back in, and put it in the right orientation. I had no issues.
 

Ewhitaker0020

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Thanks. So as long as I insert the distributor and it lines up with my mark, and I didn't rotate my engine at all, I should be good?
 

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Two marks... one from dizzy base to intake manifold, another from rotor to dizzy base. If the rotor is facing the same direction but the dizzy base has rotated, you’ve changed your timing.

Edit: since you’re replacing the manifold, a mark on the original manifold wouldn’t necessarily work, but one at 3 o’clock or another easy position on the dizzy base would be fine as well. At this point I’d try to find a buddy with a timing light or look into investing in one. If you buy one, a digital advance is worth it, imo.
 
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Ewhitaker0020

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Two marks... one from dizzy base to intake manifold, another from rotor to dizzy base. If the rotor is facing the same direction but the dizzy base has rotated, you’ve changed your timing.

Edit: since you’re replacing the manifold, a mark on the original manifold wouldn’t necessarily work, but one at 3 o’clock or another easy position on the dizzy base would be fine as well. At this point I’d try to find a buddy with a timing light or look into investing in one. If you buy one, a digital advance is worth it, imo.

What is a dizzy base? I know what direction my distributor was facing if that's what you're asking, and I made a mark to what spot my rotor was facing. Are these 2 things what I need to know?

Also a quick question. Is my distributor supposed to have any o-rings? I have a flat round gasket which I assume goes on top of the manifold? I can't find anything about it. When I googled distributor gasket it just talks about o-rings
 

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What is a dizzy base?
It’s the base, or outer lower shell of your distributor.

You’ll notice that once you get your distributor reinstalled with the rotor facing the correct direction, you can still rotate the base. In fact, if the oil drive/cam gear are properly seated, the direction the rotor is facing doesn’t matter at all, it’s just a matter of convenience. It’s the phasing relationship of the rotor/drive to the cap/base that matters.
 

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What is a dizzy base? I know what direction my distributor was facing if that's what you're asking, and I made a mark to what spot my rotor was facing. Are these 2 things what I need to know?

Also a quick question. Is my distributor supposed to have any o-rings? I have a flat round gasket which I assume goes on top of the manifold? I can't find anything about it. When I googled distributor gasket it just talks about o-rings
Flat round gasket is correct for the distributor base
 

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What is a dizzy base? I know what direction my distributor was facing if that's what you're asking, and I made a mark to what spot my rotor was facing. Are these 2 things what I need to know?

Also a quick question. Is my distributor supposed to have any o-rings? I have a flat round gasket which I assume goes on top of the manifold? I can't find anything about it. When I googled distributor gasket it just talks about o-rings


1. Don't over-analyze the process of stabbing your distributor. It goes like this:

Just temporarily install the cap. Then using a Sharpie, make a mark on the distributor showing the relative location of the cap's #1 post to the body/base (that simply refers to the part that the cap clips to).

After you have made that mark, remove the cap and restab the distributor until the driven gear engages the the drive gear on the cam.

But do be aware that as the two gears engage, the rotor will rotate a bit in the CW direction. It takes a little knack to finding that sweet spot - maybe start 15 degrees CCW from where you want the rotor to end up (i.e directly in line with the mark you made on the base).

Also sometimes on your initial attempts to drop the distributor down, the slot in the oil pump drive shaft drifts away from where it needs to be in order to accept the distributor key. Just use a long slotted screw drive to index the oil pump shaft back to where you need it to be.

When you have the rotor and mark lined up, that's it - you're done - just put the cap back on. As long as you did not disturb the relationship between the cam and distributor shaft - you should not even have to re-time the ignition. It should fire right up. At that point, you can dial the timing in as you like. The image below shows the mark and the #1 post. You can disregard the rest of the mark ups - they were for something else:

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I have only ever seen a simple gasket used to seal the distributor to the intake manifold. Like this:

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Ewhitaker0020

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I tried reinstalling the distributor exactly as I had removed it, but to make it slot in with the pump it ended up being further clockwise than it was when I had removed it. I don't know what caused this to happen as I haven't moved the truck since yesterday. So I gave up trying to do it that way and I did the #1 cylinder TDC method I read about.

I removed the #1 spark plug and kept rotating the engine until I felt the #1 cylinder building compression with my finger over the spark plug hole. When it was at the very top of the stroke, right when it started going back down I inserted the distributor with the rotor facing the #1 cylinder. When I inserted the distributor the rotor rotated clockwise a little and the shaft meshed with the oil pump drive. I ended up with the rotor facing ~6:30 or so. Is this right? I'm uploading a picture of what I ended up with.

Or do I need to end up with the rotor facing cylinder #1?

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Frankenchevy

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I tried reinstalling the distributor exactly as I had removed it, but to make it slot in with the pump it ended up being further clockwise than it was when I had removed it. I don't know what caused this to happen as I haven't moved the truck since yesterday. So I gave up trying to do it that way and I did the #1 cylinder TDC method I read about.

I removed the #1 spark plug and kept rotating the engine until I felt the #1 cylinder building compression with my finger over the spark plug hole. When it was at the very top of the stroke, right when it started going back down I inserted the distributor with the rotor facing the #1 cylinder. When I inserted the distributor the rotor rotated clockwise a little and the shaft meshed with the oil pump drive. I ended up with the rotor facing ~6:30 or so. Is this right? I'm uploading a picture of what I ended up with.

Or do I need to end up with the rotor facing cylinder #1?

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Pick up the distributor and rotate the oil pump drive 45* ccw with a long flathead, then reinstall.
 

Ewhitaker0020

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Pick up the distributor and rotate the oil pump drive 45* ccw with a long flathead, then reinstall.


Is the rotor supposed to be pointing at #1 cylinder after it's installed?
 

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Your rotor should point to here if tdc method was done correctly. It really is a simple process, dont burn your brain on it.

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Frankenchevy

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Yes, it will be roughly point at number 1 post on cap (about 5 o’clock) as @78C10BigTen said. The spark for #1 will actually happen about 10* btdc at idle.
 

Ewhitaker0020

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I want to thank everybody for their help. I think I've got this now.
 

Matt69olds

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The easiest, most sure fire way to get the distributor in and back in with no drama is to rotate the engine in the normal direction until number 1 cylinder is at TDC on the compression stroke. Line up the timing mark at 0, then remove the cap. Make a mark at the base of the distributor and the manifold, and a mark where the rotor is pointing (should be #1 plug wire) as long as you don’t move the crank, when the distributor is reinstalled and the rotor is still pointing at #1, it should be close enough to start.



You can also “static” time the engine. Once again, rotate #1 on the compression stroke, but this time stop the crank with the timing mark at the desired initial timing setting (for example,10 degrees BTDC). Then install the distributor with the rotor pointing to number 1, and rotate the distributor housing until the triangle shaped magnets on the distributor shaft, and the pickup coil line up. Tighten the distributor with the magnets lined up. Start the engine, assuming there is little toming chain slip you will find the ignition timing within a degree or 2 of where you want it to be.
 

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