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I sent my distributor to Dan and I will get it back tomorrow. I need to know how To place it back in the correct spot (timing).

I'm pretty sure I need to put cylinder 1 at TDC and match the rotor with cylinder 1 of the cap.

Without removing the valve covers how can I know if 1 is at TDC? Remove the spark plug? Would I need to get a bore scope?
 

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Pull #1 spark plug. Have someone turn the engine over with a socket and breaker bar while you have your finger stuck in the hole. When you feel pressure building up, remove your finger and watch the balancer and keep turning until the marks line up. Stab in the dizzy with the rotor pointing at #1 tower. Viola.
 

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No. Remove #1 plug. rotate the crank by hand until you feel compression on your thumb. It will then be on the compression stroke. Rotate crank until piston is at the top of its stroke, pressure will stop. It's pretty intuitive. Aim distributor vacuum canister towards front of car and position rotor just to the right of 1 on the cap. Install distributor. Should be pretty close. Start it and adjust as needed. If you do get it off by a toothe one way or the other, pull it out just enough to adjust and reinstall.

EDIT: Sorry Bart. Didn't mean to type over you.
 

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Sometimes the oil pump shaft will not be lined up exactly like you need it to set the distributor all the way in. If this happens, use a 1/4" deep socket with an extension and turn the shaft enough to get the distributor to sit all the way down. It might take a few times to get it right.

Tim
 

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In a perfect world, shouldn't the balancer be lined up on the timing pointer at TDC? Granted, its still a good idea to confirm TDC as Bart and the others have mentioned. If the pointer and balancer don't match up, I'd imagine you might have a hard time getting the timing right.
 

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Sometimes the oil pump shaft will not be lined up exactly like you need it to set the distributor all the way in. If this happens, use a 1/4" deep socket with an extension and turn the shaft enough to get the distributor to sit all the way down. It might take a few times to get it right.

Tim
If you do this tape the socket to the extension/s. Trust me.

Sent from my SM-N910V using Tapatalk
 

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In a perfect world, shouldn't the balancer be lined up on the timing pointer at TDC? Granted, its still a good idea to confirm TDC as Bart and the others have mentioned. If the pointer and balancer don't match up, I'd imagine you might have a hard time getting the timing right.
In a perfect world, the pointer would line up to whatever the initial timing should be set to and the rotor to #1 tower. That would require no other adjustment. The perfect world doesn't exist, however, and that's why the distributor rotates.
 
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I sent my distributor to Dan and I will get it back tomorrow. I need to know how To place it back in the correct spot (timing).

I'm pretty sure I need to put cylinder 1 at TDC and match the rotor with cylinder 1 of the cap.

Without removing the valve covers how can I know if 1 is at TDC? Remove the spark plug? Would I need to get a bore scope?
Take a small piece of toilet paper and push it slightly in the spark plug hole. Rotate the engine by hand . . when the paper pops out ( and it will ), you are on the compression stroke. TDC is right at the end of that, so move the engine until the pointer lines up with zero. It will be very close once the paper pops out.
 

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...and that's why the distributor rotates.
I thought it rotates to fire on the particular cylinder the rotor is pointing to on the cap? Kidding, of course...

However, in a "perfect" lined-up-with-timing-pointer-pointing-at-TDC world, the piston would be all the way up.

What is the measurable distance that the piston travels from 0 to 6 degrees?
 
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Remember that at the top, some crank rotation causes the pistons to more . . . nowhere.
 

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What is the measurable distance that the piston travels from 0 to 6 degrees?
That would depend on the stroke, rod length, and where the piston is in the stroke. In the middle of the stroke, it would be 6/360ths of the stroke. At the top and bottom of the stroke it would be far less as the crankpin is moving almost parallel to its centerline.
 

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I guess the bigger question is where is the ideal position of where the piston is when the cylinder fires and why is 6 degrees so significant and the standard for most of our cars?

This is class, and I'm taking notes. Sorry for all of the oddball questions...

:cheers:
 

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I guess the bigger question is where is the ideal position of where the piston is when the cylinder fires and why is 6 degrees so significant and the standard for most of our cars?

This is class, and I'm taking notes. Sorry for all of the oddball questions...

:cheers:
Gasoline doesn't explode but burns. You have to light the fire early so that the fire has reached its' maximum strength when the piston is at TDC so that the pressure pushes the piston down at the correct time. If the fire reaches its' max before the piston reaches TDC the pressure tries to push the piston down before TDC and bad things happen.
The faster the RPM the sooner you have to start the fire. That's why the distributor has advance mechanisms. With the engine idling you only need to light the fire around 10* BTDC but at 6000 RPM you need to light it around 36* BTDC. There are some very scientific formulae to compute all this but that's the story in a nutshell.
 

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If the OP had made note of the rotor position before he removed the distributor the distributor could be dropped back in using that orientation. Eliminating all of this cranking and toilet paper. That assumes the engine wasn't turned while the distributor was out. Dave R.
 

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Discussion Starter #19
If the OP had made note of the rotor position before he removed the distributor the distributor could be dropped back in using that orientation. Eliminating all of this cranking and toilet paper. That assumes the engine wasn't turned while the distributor was out. Dave R.
Ya, that's where I made a rookie mistake. I marked the distributor not the rotor. I realized my mistake as soon as it was out.

Hence this post lol.
 

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Discussion Starter #20
In a perfect world, yes. But as you say sometimes that isn't plausible. For instance, if the balancer is not marked, or if the pointer is broken off or missing.
I'm pretty sure the balancer isn't marked so pulling #1 spark plug.

Sometimes the oil pump shaft will not be lined up exactly like you need it to set the distributor all the way in. If this happens, use a 1/4" deep socket with an extension and turn the shaft enough to get the distributor to sit all the way down. It might take a few times to get it right.

Tim
If you do this tape the socket to the extension/s. Trust me.
Sounds like you have a story to tell!
 
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