Timing is everything..Electronic Ignition....?

[splashlog]

Finally got my ignition troubles dealt with. Now, anyone have insights into how to RE time this bad boy now that I have probably messed up the timing real good. It now has the electronic ignition module installed, and it's the old Prestolite Distro. I know where TDC is as I have made a mark, do I just turn the crankshaft until I get a spark on #1 plug and then pray?

[ndutton]

Originally Posted by splashlog

I know where TDC is as I have made a mark

Please describe this mark. Where is it and how did you make it?

[splashlog]

Apparently the pins on the drive shaft that are used to rotate the shaft indicate TDC or BDC. I just rotated the shaft until I had max compression and then marked that pin. I realise it's rough, but should get me in the ball park, no?

[ndutton]

Yes, all correct but please know that the mark you made for the top of the compression stroke will also indicate the top of the exhaust stroke. When setting the timing initially it is imperative you are certain which stroke you are on.

[splashlog]

So with the crank shaft at TDC and the roll pin vertical, where should the rotor on the distro be pointing? Right now it's pointing 3 O'clock, but that would mean it's poised to fire plug #4, not #1 as I would assume to be what we need.
The original set up in terms of plug wires off the distro was plug wire #1, 9 OC, #2, 12 OC, #4, 3 OC, #3, 6 OC (1,2,4,3)

I thought I had been fairly careful in keeping the realative position correct of the distro as I had removed/installed it several times, BUT I never checked where the crankshaft was positioned.

I have the EI installed now, if anyone has a step by step procedure, well that would just make my day...

It's the Prestolite Distro with Electronic Ignition

[JOHN COOKSON]

Originally Posted by splashlog

S
plug wire #1, 9 OC, #2, 12 OC, #4, 3 OC, #3, 6 OC (1,2,4,3)

Firing order facing the engine from the front or flywheel end I presume?
If the engine was rotated while the distributor was out you will have to ascertain if the mark you made is at TDC compression or TDC exhaust.
The easy way to do a distributor removal into put #1 at TDC compression before taking the distributor out and not rotating the crank while the distributor is removed.

TRUE GRIT

Edit: Maybe you can feel the compression as you rotate the engine. See your manual page 3-2.

[splashlog]

Facing the flywheel. I can feel the compression @ TDC. So please correct me here, the rotor needs to be pointing at the contactor in the cap to fire that plug, right? So it makes no difference which contactor is which as long as the rotor is firing the correct plug and the squence is 1,2,4,3.
With an EI, could I use an multi meter and measure for continuity or ohms to figure out the open/closed state for fine tuning?

[ndutton]

I'm not saying this is the case but regarding my earlier caution, if #1 piston is at the top of its travel on the exhaust stroke, the rotor should be pointing at #4!!! (because #4 would be at the top of its travel on the compression stroke)

It does not matter where the rotor points on a clock dial, what matters is #1 TDC on compression stroke gets the rotor in contact with the distributor cap delivering spark to #1. The orientation we talk about often is only a convention on this forum, has nothing to do with the actual timing.

[Sam]

To me little Prestolite dizzy [w/condenser hanging on side and oil cup] means early model. Detail steps are spelled out in Moyer tech pages. Basically, pull the distributor, get to TDC on compression stroke [thumb test, balloon test etc], the front shaft pin now near verticle. Reinstall dizzy with rotor and #1 pointing directly aft. Now your close and you have a lot of rotational clearance to adjust timing.. manually if you like.

[splashlog]

The Atomic Four has a firing order of 1 2 4 3, and the crankshaft is designed so that pistons #1 and #4 go up and down together (and so do pistons #2 and #3, but 180 degrees out... when pistons #1 and #4 are at the top together, pistons #2 and #3 are at the bottom together). The reason to know this is that when piston #1 is at the top its firing stroke... firing #1 cylinder, piston # 4 is at the top of its exhaust stroke and just starting to do down on its intake stroke... with the exhaust valve just closing and the intake valve just opening, AND YOU CAN SEE PART OF THE INTAKE VALVE FOR #4 CYLINDER TO DETERMINE WHEN IT IS JUST STARTING TO OPEN BY LOOKING STRAIGHT DOWN #4 SPARK PLUG HOLE (IT'S THE ONLY VALVE YOU CAN SEE LOOKING STRAIGHT DOWN).

So, remove the spark plug for #4 cylinder (it's easier if you remove all the spark plugs) and turn the engine by hand in the direction of rotation (counterclockwise facing the flywheel) while looking straight down the #4 spark plug hole with a flashlight (if you can't look straight down the plug hole use a little piece of wood such as a popsicle stick to feel the valve going up and down). As the engine turns you will see the intake valve in #4 cylinder rising and falling. Carefully turn the engine over and stop just as you see the #4 intake valve just starting to open. That will mean #1 cylinder is now at the firing position, so remove the distributor and install it so both the rotor and the wide protrusion in the side of the distributor points plate (which fits into a slot in the distributor cap to align it) both point at 9 o'clock (looking down on the top of the distributor facing the flywheel). Once the distributor is in leave the distributor clamp loose, and install the cap, spark plugs, and spark plug wires, making sure the plug wire for #1 cylinder goes in the 9 o'clock postion, #2 plug wire goes in the 12 o'clock position, #4 plug wire goes in the 3 o'clock position, and #3 plug wire goes in the 6 o'clock position. Once the engine starts turn the distributor slightly back and forth so it runs the fastest. When everything is back in place time the engine at full speed as per the section on timing above.

[Administrator]

You can find a helpful video tech tip here. There are both PC and Mac versions.

Bill

[ndutton]

splash, whatever works for you. In your research did you find this post from last year? It's a simple tool that costs pennies and eliminates peering down spark plug holes to watch valves.

[splashlog]

Yes, I will make that balloon tool, however other distractions are aloof. I am wondering now about something else; when I hit the start button, my starter spins up and engages, yet only very briefly, usually not long enough to get a good bite on the flywheel.

(I did jump the gun and install a new alternator mainly because finding the vintage voltage regulator that I had broken was more trouble than it's worth. So now I have a 65A alternator in place of the original 35A Prestolite....)

So the question is, would the new alternator affect the preformance of the starter? Is there perhaps too much load on the system now that the starter (bendix) just does not want to play? Or, am I just unlucky and that this is one more issue that I need to look at, like is it time to pull the starter and have a little poke about? The starter was begining to miss every now and then, but allways managed to hang in long enough to get things going. But now she spins and just makes a quick attempt at grabing the flywheel but then just spins out. This is making me lose my mind, as I am still trying to get this engine to turn over and get the timing sorted.

[ndutton]

Originally Posted by splashlog

So the question is, would the new alternator affect the performance of the starter?

No, the two are mechanically unrelated.

[Dave Neptune]

Splash, the timing, alternator and starter are 3 separate systems.

First, the starter. The bendix could be sticking from dirt or lack of lubrication and/or a weak battery (connection) not twisting the bendix fast enough to force the gear out into the flywheel. This can also be form a weak solenoid. And if the battery is low that may be all it is.

Second, if the alt is in place it may be easier to just remove it if it is in the way. You can start and run the engine for a while without it.

Third, timing. With all 4 plugs removed and a bit of spray oil into each cylinder you should be able to rotate the engine by hand. I could move mine by hand with the accessory drive, a strap wrench like for an oil filter will work too. Now rotate the engine until the flywheel pin is horizontal. Now place your thumb over the desired cylinder 1 or 4. With your thumb over the plug hole rotate the engine the last 90 degrees and you will feel your thumb being pushed off the hole if on compression and nothing if on the exhaust stroke.

Fourth, now you have the compression stroke figured and it's time to drop in the distributor to your desired reference position and line up the #1 or #4 cap post to the rotor and y'er ready to play.

One step at a time. No pun intended.

Dave Neptune

[JOHN COOKSON]

Originally Posted by Dave Neptune

Splash, the timing, alternator and starter are 3 separate systems.

And if the battery is low that may be all it is.
Dave Neptune

R\E "low battery":
There may be corrosion in the wiring connections battery -> starter. Don't forget to check both hot and ground sides of the circuits.
Are all connections bright and shiny and is the wiring in good condition?

TRUE GRIT