Top entry distributer cap?

[Millrat]

Finally recieved my backordered generator from Moss after about 4 months. The charging system seems up to snuff now and I would like to put new plug wires on. How do I keep the plug wires straight changing from side entry to top entry? I have the cap and wires but not the intestinal fortitude to make the switch:confusion:.

 

[Trevor Jessie]

note the number one position, then follow the firing order 1342

 

[Pythias]

You CAN do it. Since you know the firing order from above, the worst that can happen is that you're out of rotation, not out of order.

 

[Millrat]

So I have an amatuer ?. Is the #1 piston at the front of the engine? If so I would assume that it would be a matter of tracing that wire back to find the rotor position and then go counterclockwise in the proper firing order.

 

[Pythias]

Set the timing pointer to mark on the pulley to the mark so it aligns with the zero timing mark. When you pull the dizzy cap off, it will be pointing at #1. Rest the new cap in place and that will tell you which hole is the number one hole. as the rotor will be pointed directly at it. Then counter clockwise .. go 1 3 4 2 .. front to back on the engine.

 

[dklawson]

I have just one tiny addition to Bill's method above. The rotor can be pointing anywhere if the dizzy drive gear has been removed at some time in the past such as during an engine rebuild. To make sure you have found #1 at/near TDC on its firing stroke, remove the spark plug from cylinder #1 (water pump end of block). Look for the piston at/near the top when the Zero degree timing marks line up. Now remove the valve cover and grab the rocker arms for cylinder #1. You should be able to "wiggle" them. That indicates that #1 is at the beginning of its firing stroke and the valves are closed. If the rocker arms are angled down and "tight" so you cannot move them, turn the engine over one more complete revolution.

 

[Bayless]

Just one more little trick to find #1 firing. Remove the #1 sparkplug then as you turn the crank to align the timing marks, it will turn with little resistance when #1 is in position to fire. If it is #3 instead (another turn of the crank is needed) there will be significant compression resistance. A lazy man will figure out how not to remove the valve cover.

 

[dklawson]

If it is #3 instead (another turn of the crank is needed) there will be significant compression resistance.

I believe you mean #4 instead. 1 & 4 are "up" at the same time that 2 & 3 are "down".

 

[Millrat]

You CAN do it. Since you know the firing order from above, the worst that can happen is that you're out of rotation, not out of order.

Thanks for all the input. Does it make a difference in performance to be out of rotation?

 

[Bayless]

Thanks for the correction Doug (slaps self upside the head) Sometimes I talk or type faster than I think. (See my sig) I hope the idea came across anyway.

 

[dklawson]

Thanks for all the input. Does it make a difference in performance to be out of rotation?

If you have the wires on the correct plugs for the firing order, no it does not matter (performance wise) where the plug wires are around the cap. Obviously putting the wires on in the wrong order will cause problems. Generally the only issue with the distributor drive in the wrong position is you might be unable to rotate the distributor body to the position you want/need to achieve the correct ignition timing due to interference from the vacuum advance unit.

That being said, IF you were talking about air cooled VWs, having the distributor in the correct position and the plug wires on in the correct order can be important. Because of oil cooler placement and the extra heat on one cylinder (#3 ?) they have a different dizzy cam profile for that cylinder. But I digress... that has nothing to do with an A-series engine.

 

[Pythias]

Does it make a difference in performance to be out of rotation?

Yes it makes a difference. Your car won't run at all.

 

[Millrat]

So now I am confused. Not that it doesn't happen on occasion:topsy_turvy:. Obviously I would like to be correct all the way around. The next best thing is to have the car run in blissful ignorance in correct firing order but out of rotation. The thirty plus year old wires and cap work okay now, but will fail the minute my wife gets more than 5 miles from home. This car has been the best entertainment I've been able to put money into for a long time.

 

[The_architect]

See if this picture doesn't help you see what the order is. Okay, one at a time, transfer your wires from the old to the new, standard distributor cap, making sure that the places where the clips go are lined up in the same way on the new cap as the old one. The distributor in your car may be installed 180 degrees differently than this, but you should be able to tell this just by looking. Just trace the wires and see which one is going to #1. Or better yet, post a photo and someone will tell you. Don't overthink this. It is very simple.
.

 

[dklawson]

OK... let me clarify my last post a bit.

Yes the firing order has to be correct. The plug wires do have to go around the A-series distributor cap 1-3-4-2 counterclockwise with plug wire #1 being the cylinder closest to the water pump. When the distributor drive gear is in the block correctly per the factory position, this will have the rotor in the dizzy pointing to about 1:00 to 2:00 o'clock when cylinder #1 is at/near TDC on its firing stroke.

However, during an engine rebuild it is not uncommon to insert the dizzy drive gear in the block in the "wrong" position. That means that when you put the dizzy in and bring #1 piston to TDC on its firing stroke the rotor is NOT going to point at the 1:00 to 2:00 o'clock position. That is not the end of the world. You can either use a long bolt to pull, rotate, and re-position the distributor drive gear OR you can re-locate the plug wires around the cap. Moving the drive gear leaves everything "stock" and will prevent future confusion. It is preferred. However, if you are in a hurry or don't want to be bothered, you CAN reposition the plug wires around the dizzy cap. To do this, you install and static time the distributor as you normally would. That requires you have the engine sitting at your desired timing mark with #1 cylinder at the beginning of its firing stroke. After setting the static timing, look at where the rotor is pointing. Place the dizzy cap on the distributor and note which cap terminal the rotor is pointing at. The plug wire for cylinder #1 goes there. The others follow in the order 1-3-4-2 counterclockwise around the cap.

Placing the wires like this maintains the firing order. However, the wires are repositioned (not in the factory locations) to compensate for the dizzy drive gear being in the wrong orientation. In essence you have rotated the plug wire positions to compensate for the drive gear position. I'm sorry that I didn't make that more clear in my previous post.

 

[Millrat]

See if this picture doesn't help you see what the order is. Okay, one at a time, transfer your wires from the old to the new, standard distributor cap, making sure that the places where the clips go are lined up in the same way on the new cap as the old one. The distributor in your car may be installed 180 degrees differently than this, but you should be able to tell this just by looking. Just trace the wires and see which one is going to #1. Or better yet, post a photo and someone will tell you. Don't overthink this. It is very simple.
. View attachment 26166

That should do the trick! Thanks all for the input. I don't know if the engine has been rebuilt, but it was painted red at some point 30+ years ago. everything on it seems stock and does'nt look disturbed but what is the difference between 30 and 50? I will post as to my success.