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Tue Apr 29, 2025 10:50 am

heimlich wrote: The distributor looks ok. It may need a shim but it is not excessive.

I've always heard not to rotate the engine with the distributor drive removed. Engine builders put a distributor in the hole when they ship it so that the gear will not move around.
With the distributor drive shaft removed, You can, rotate the engine.
Pay attention as to where you are in the engine rotation. You want to get it back to TDC for #1 when you reinstall the distributor driveshaft.

It's when the drive shaft is in the engine and the distributor is removed, rotating the engine CCW can likely damage the brass crankshaft timing gear.

Tue Apr 29, 2025 11:10 am

OK. So maybe what I heard was not to rotate with the distributor removed. Without the distributor holding down the gear it creates an issue.

Tue Apr 29, 2025 11:15 am

I turned the engine 360*, carefully so as to end up back at TDC, and could not see any damage, other a couple of surface scratches, on the brass gear. I watched it thru the fuel pump access and the distributor access. Nuthin'. Picture's as best as I could manage w/the phone.

Perhaps I should just add a shim under the distributor shaft, reinstall the drive gear this time properly aligned to the center case line and retest. Maybe I've always had this problem and just didn't realize it??? I doubt that though.

Tue Apr 29, 2025 11:32 am

Victor,
Verify your engine is back at TDC for the #1 cylinder by removing the valve cover and wiggling the rockers for #1.
They must be at TDC in order to get the engine timing right.

Tue Apr 29, 2025 11:41 am

For your distributor it doesn't matter how the distributor drive gear is oriented. All you have to do is set the engine to TDC. Then you can reorient the distributor and then reorient the wires. All that matters is that when you have the engine at TDC that where the rotor points you attach wire #1. If you get it a little off from TDC that is ok.

Tue Apr 29, 2025 12:06 pm

67, confirmed, it's at TDC for #1.

heimlich wrote: For your distributor it doesn't matter how the distributor drive gear is oriented. All you have to do is set the engine to TDC. Then you can reorient the distributor and then reorient the wires. All that matters is that when you have the engine at TDC that where the rotor points you attach wire #1. If you get it a little off from TDC that is ok.

Heimlich, do you mean that I can rotate the distributor so that the vac can is at an easy to manage orietation, then just rotate the wires so #1 points to where ever that happens to be? Same thing 67 suggested higher up I guess?

Tue Apr 29, 2025 12:12 pm

vamram wrote: 67, confirmed, it's at TDC for #1.

heimlich wrote: For your distributor it doesn't matter how the distributor drive gear is oriented. All you have to do is set the engine to TDC. Then you can reorient the distributor and then reorient the wires. All that matters is that when you have the engine at TDC that where the rotor points you attach wire #1. If you get it a little off from TDC that is ok.

Heimlich, do you mean that I can rotate the distributor so that the vac can is at an easy to manage orietation, then just rotate the wires so #1 points to where ever that happens to be? Same thing 67 suggested higher up I guess?
That is correct. I just didn't explain it well last night. :oops:

Tue Apr 29, 2025 12:13 pm

67rustavenger wrote: vamram wrote: 67, confirmed, it's at TDC for #1.
...Heimlich, do you mean that I can rotate the distributor so that the vac can is at an easy to manage orietation, then just rotate the wires so #1 points to where ever that happens to be? Same thing 67 suggested higher up I guess?
That is correct. I just didn't explain it well last night. :oops: :lol:

Tue Apr 29, 2025 12:18 pm

vamram wrote: …..And the edges of the brass gear look ok, although it *may* have a gash on the inside of the "center" spiral. Hard to see in the pictures. I have *not* rotated the engine w/all of this removed. Would it be ok to do so, in order to see all edges of the brass gear?

Can you get a better picture of the gear? It looks a little worn, based solely off of the pointyness of the gear teeth!

What were the measurements you took of the depth of the case to slot? And the distributor body cog?

If you answer, I may have your solution but I am not going to write the entire process out for you without knowing those. It is just too much if the issue is moot.

Also. That is some serious wear mark in that distributor bore. What is up with that? Any idea how that happened? I have never seen a mark like that before, unless something spun for awhile right there. Oooo ooo! Mr. Cotter! Maybe the distributor has more play side to side due to that wear. Can you push and pull on the distributor, you side to side, not in and out of the case. And not the shaft, but the body?

And you can rotate all you want to. Often times the distributor drive gear will ride up, IF there is no fuel pump installed. If you still have the fuel pump installed, rotate away. You are not going to damage anything. It is designed to turn in circles!

Tue Apr 29, 2025 12:28 pm

vamram wrote: 67, confirmed, it's at TDC for #1.

heimlich wrote: For your distributor it doesn't matter how the distributor drive gear is oriented. All you have to do is set the engine to TDC. Then you can reorient the distributor and then reorient the wires. All that matters is that when you have the engine at TDC that where the rotor points you attach wire #1. If you get it a little off from TDC that is ok.

Heimlich, do you mean that I can rotate the distributor so that the vac can is at an easy to manage orietation, then just rotate the wires so #1 points to where ever that happens to be? Same thing 67 suggested higher up I guess?

Yes. Put it in at TDC. Rotate it (preferable in 90 degree segments). There are 4 90 degree segments in your distributor corresponding to the 4 cylinders. Then just attach the #1 wire to the terminal right above the rotor. Rotor is pointing to #1 at TDC. There's a few distributors you can not do this with but yours is fine.

67 has the same idea.

You can't do this in fuel injected or if the distributor has an offset.

Do you have the shims that go under the drive? If I recall correctly someone said to use a pencil to line up the location so the shims don't go in the engine. Whatever you do don't just try to drop them on there.

Tue Apr 29, 2025 12:49 pm

Jimbo - If I'm understanding you:

Depth case edge to bottom of distributor slot where the shims would rest: 134.29mm approximately.

Base of distributor - face that sits on the clamp to the lower tip of the cog: 50.68mm.

Tue Apr 29, 2025 1:33 pm

vamram wrote: Jimbo - If I'm understanding you:

Depth case edge to bottom of distributor slot where the shims would rest: 134.29mm approximately.

Base of distributor - face that sits on the clamp to the lower tip of the cog: 50.68mm.
Almost correct. Place the distributor drive in the case and measure from the case edge to the top of the drive where the cog sits in the groove. Not the groove just the flat top of the drive.

Next, measure from the bottom of the clamp to the flat portion of the drive cog.

Tue Apr 29, 2025 2:56 pm

67, I didn't see your explanation before I started on it again. I was able to reorient the drive gear so that the vacuum can now looks normal when timed - facing straight back as opposed to towards the v-belt.

However, the problem remains. I was able to get the dvda back in and timed, but neither one of my Bosch 034s will catch. So at the very least I need a couple of shims under the gear.

I'll redo the measurements tomorrow using your instructions.

Tue Apr 29, 2025 8:30 pm

What is the difference between the two distributors at that dog?

Wed Apr 30, 2025 10:12 am

Here's what I came up with:

1. Top edge of Dist. slot to top of the distributor gear, not the groove:
47.5mm

2. Length of DVDA shaft to bottom of cog, not including the 2 anchors/teeth:
46.12mm
Clamp: 2.52mm

3. Same as #2 for the SVDA:
45.64MM
Clamp: 2.48 mm

I used my micro-meter for the measurements, but ya gotta figure there's a bit of slack. I used an unsharpened pencil which I notched to measure #1, measuring the distance from the end to the notch.

Wed Apr 30, 2025 11:35 am

Hmmmm!
If I'm adding correctly. The difference between 1. and 2. including the clamp thickness is 1.14mm.
Yet the cog teeth don't engage the drive groove.

The depth of the distributor cog teeth is 4.77mm, I measured two of mine sitting on my bench.

The distributor should engage the drive based on the above measurements

I have a suggestion, but I'm not gonna post in the open forum.
I'd get flamed to death! :D

Victor, I'll shoot ya a quick PM in a few minutes.

Wed Apr 30, 2025 11:47 am

Looking forward to that suggestion!! :lol:

Yeah, that miniscule difference is enough to keep the SVDA cog from engaging, and also why I can relatively easily pop the DVDA out of the cog slot, simply w/the minor vertical play in the dizzy.

Would adding a shim or 2 to between the cog and the DVDA shaft be acceptable....?

Wed Apr 30, 2025 12:08 pm

Failing what I suggested, yeah maybe it's time for a single shim under the driveshaft to raise it a few thousands.

Give what I suggested a try. I've had a few stubborn distributors in the past.

Wed Apr 30, 2025 12:35 pm

I'll take it for a drive later to see if it pops out of the slot again. Regardless I think it's time for an additional shim or two under the drive gear. Probably just a band-aid to a deeper problem, eh?

That said, it's in and holding. Now what about this turning slop? Probably 30-40* of play when I grab and turn the rotor counter or clockwise. Is this normal, or is this an indication of a worn brass or other gear?

Wed Apr 30, 2025 12:41 pm

vamram wrote: I'll take it for a drive later to see if it pops out of the slot again. Regardless I think it's time for an additional shim or two under the drive gear. Probably just a band-aid to a deeper problem, eh?

That said, it's in and holding. Now what about this turning slop? Probably 30-40* of play when I grab and turn the rotor counter or clockwise. Is this normal, or is this an indication of a worn brass or other gear?

It appears that the return spring isn't working.
You need to remove the pick up mounting plate and verify that the spring is in place or broken. It should spring back when twisted/advanced.

Do both distributors act like that?