Help - Distributor install questions (devil is in the details)

[soundquest]

97 Vortec 5.7 (K1500). Since all threads on distributor installation have only bits and pieces of proper installation, and non of them are "complete" as there are some rather important intricacies that always manage to get glossed over... I am asking for a few points of clarification (and let me just say, I can't believe how complicated GM made it).

First point of clarification -- there are two different styles of Distributor hold-down. One allows for distributor adjustment and rotation, and the other one absolutely LOCKS the distributor in place, leaving no room for adjustment (what the???!!!). So the question becomes, why do aftermarket distributors (most) come with these ridiculous non-adjustable hold-downs, when they know they will need to be rotated? And second... short of modifying this non-adjustable hold down via cutting and grinding, do the brick and mortar stores carry the adjustable hold-downs? (and didn't they come from the factory with the adjustable style?)

I am in possession of a modified hold-down (cut and ground -- see picture link below) -- can I trust this thing (pictured) or should I hold out for a brand new adjustable style? https://drive.google.com/file/d/1BsC9wr2xUJL5-PyuhYVu9nFpOe3DrZVK/view?usp=sharing

Second -- what is the best way to align the oil pump shaft to received the distributor shaft?

Thanks all in advance.

 

[L29Sub]

The hold brackets are cheap. Get one for an adjustable distributor and be done with that.
Be sure you have the engine at #1 TDC compression stroke.
The oil pump shaft is a PITA. You'll want the rotor electrode facing forward when engaged with the cam gear and oil pump shaft. You've gotta back the rotor up a fraction of a turn so that it drops in with the rotor generally forward (towards carb).
Once you get close, look at the position of the distibutor shaft when carefully pulled out after engaging the cam gear, but not aligning with the pump. Take a long, clean screwdriver or an oil pump primer and carefully position the oil pump shaft notch as close as possible to the dist shaft. Drop the distributor in and see if it drops all the way down. If not, rinse and repeat. Move the pump shaft slightly and try again. It'll go in once its positioned correctly. And it won't go in unless the pump shaft is about spot on. You can see the pump shaft and get it close...and just advance a tiny bit with each try.
GM hei distributors are not position sensitive, but, you best be able to work out the plug wire positions ad-lib. Some pre-cut wiring won't allow for #1 being on the back or pax side. The distributor timing will require some adjustment. If using a vacuum advance, install so that nothing interferes with the vacuum advance being moved a little either way.
The electronic factory distributors have an electronic base advance that communicates with the ECM. Reads cam or crank sensor and sets it's own timing correctly. Still, it must be within the base circle. They also must be accurately installed with #1 in correct position. These may be non-adjustable....or not.




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[L29Sub]

The two adjusters pictured are the same. One has longer fingers for easy install. They are for adjustable distributors. They come in some really cool aluminum anodized colors too.
Even though adjustable, once locked down, the dist won't move. Snug up, set timing, lock down.

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[delta_p]

Take the pin out of an old distributor to disassemble it and use the shaft to monkey with the oil pump. it'll fit better than a screwdriver for alignment.

You must be registered for see images attach

 

[east302]

I reused my old hold-down clamp on the new distributor. Tossed the fixed one in the trash.

 

[Allen4rmGromLak]

If I can't get the oil pump shaft to align up. I drop the distributor in as far as it goes (proper alignment with #1) and instead of trying to fish something and turn the shaft, I bump the engine over. Dizzy drops down onto the shaft and my timing is still in time due to the camshaft and dizzy was turning at the same rate of each other. Been doing that for 25+years.

 

[Allen4rmGromLak]

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Starts at 2:20 what I was trying to explain

 

[What?]

Long flat head or file. Use it to turn the oil shaft a bit at a time.

As someone mentioned above, using old dismantled distributor will help re-position it a bit. It's not adjusting like previous ones does as the sensors will do that with the ECM.

 

[soundquest]

That repurposed distributor idea is genius (as is the starter-bump method... but that method scares me too much -- I just see gear pieces going flying everywhere inside the engine with my luck). So to close this out (and I am sure all of your input will likely help some poor old soul working through a similar quandary in the future)... I will let y'all know that I was able to successfully install the dist and was able to successfully set the CMP offset (cam retard) via DashCommand, GM PID Add-on package, and a $10 OBDII dongle from Amazon. And... the engine now runs like a top at 0.00 to -0.20 at 1000 - 1200 RPM. It's never run this good in fact. Hot damn!