318 LA Rotor position and TDC questions

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JeffreyLee

JeffreyLee

1965 Barracuda
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Hi Guys,
I am getting ready to fire up my 318LA engine after a lot of careful work.
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I am cutting and installing my plugs today. I set TDC on #1 cylinder when I installed my new timing chain aligning my timing marks to indicate that. Dropped in the new distributor, rotated my crank until the distributor rotor points at the intake bolt closest to the #1 cylinder.....Right so far? Now that things are all lined up, the timing mark is not even visible, which means that cylinder #1 is not at TDC right? If I keep going without knowing if there's a problem to correct, I might foul this whole thing up. Any thoughts? Thanks
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The slot in the dist/oil pump drive gear should point to the front left intake bolt when #1 is at TDC.

That dist needs to be rotated quite a bit. Vac advance should point a lot more towards the fendrrwell.


in reality it really doesn't matter as long as the rotor points to #1 at TDC and ll the wires are done accordingly.
 
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find TDC on #1 cyl an let us know (picture preferred) where the rotor is pointing. maybe you Are just 180 out.
 
If you aligned the dots at 6 o'clock on the cam and 12 o'clock on the crank, you are firing #6 cylinder.
 
JeffreyLee said:
I set TDC on #1 cylinder when I installed my new timing chain aligning my timing marks to indicate that. Dropped in the new distributor, rotated my crank until the distributor rotor points at the intake bolt closest to the #1 cylinder.....Right so far? Now that things are all lined up, the timing mark is not even visible, which means that cylinder #1 is not at TDC right? If I keep going without knowing if there's a problem to correct, I might foul this whole thing up. Any thoughts? Thanks
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Mmmmm... no, not right so far.
  1. If you lined up the dots on the timing chain with the dot on the cam sprocket at 6 o'clock, and the dot on the crank sprocket at 12 o'clock, then both #1 and #6 are at TDC, and it is #6 that is firing with the timing chain sprockets aligned in that manner, not #1.
  2. You don't rotate the crank to line up the rotor. You keep the crank where it was when you set up the timing chain, and pull up and drop back in intermediate shaft over an over until the slot in the shaft points to the #1 intake bolt as said. THEN you drop in the distributor with the rotor pointing in the opposite direction, which is #6 spark tower.
Do you know if you rotated the crank less than 1 full turn? If so, then rotate it another full turn and then some more until the external (ignition) timing marks line up at 0... so that you are back where you started. (In other words, 2 full turns from where you started.)

Please confirm that you set the timing dots as described above, at 6 and 12 o'clock, so we can be sure what you have. If not, then a valve cover can be removed to get things all sorted out again.
 
I'm trying to think back about how i aligned my marks on the timing gears at the time. Here's a pic. I recall lining up the upper gear and lower gears so that they were closest to one another at 6:00 and 12:00.. That oil slinger is in the way, so I can't see the bottom gear in the pic. 90% sure I did it the right way. When I rotate the crank so that the timing marks indicate TDC, the slot is pointing right down the middle of the engine...Does that distributor drive gear only fall into place one way? Can I lift it out partially and rotate it so it is pointing correctly?
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nm9stheham said:
Mmmmm... no, not right so far.
  1. If you lined up the dots on the timing chain with the dot on the cam sprocket at 6 o'clock, and the dot on the crank sprocket at 12 o'clock, then both #1 and #6 are at TDC, and it is #6 that is firing with the timing chain sprockets aligned in that manner, not #1.
  2. You don't rotate the crank to line up the rotor. You keep the crank where it was when you set up the timing chain, and pull up and drop back in intermediate shaft over an over until the slot in the shaft points to the #1 intake bolt as said. THEN you drop in the distributor with the rotor pointing in the opposite direction, which is #6 spark tower.
Do you know if you rotated the crank less than 1 full turn? If so, then rotate it another full turn and then some more until the external (ignition) timing marks line up at 0... so that you are back where you started. (In other words, 2 full turns from where you started.)

Please confirm that you set the timing dots as described above, at 6 and 12 o'clock, so we can be sure what you have. If not, then a valve cover can be removed to get things all sorted out again.
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I think that you answered my question, I just need to pull the distributor shaft out a bit and re align it pointing properly. BTW, how do I reach way down there and get ahold of the distributor gear to move it? Long needle nose I guess?
 
Pull #1 spark plug out and rotate the engine with your finger over the hole... Then when you feel the pressure push up on your finger note where the rotor is... Then turn the crank until the timing marks on the vibration damper and timing chain cover line up on the stroke that you feel the pressure on, that's the compression stroke on #1 cylinder...

Now were ever the rotor is pointing when you have the crank at TDC, then start with that terminal and make it #1 on the cap and then install the rest of the spark plugs in firing order in the direction of the rotor rotation... 1-8-4-3-6-5-7-2...
 
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JeffreyLee said:
I think that you answered my question, I just need to pull the distributor shaft out a bit and re align it pointing properly. BTW, how do I reach way down there and get ahold of the distributor gear to move it? Long needle nose I guess?
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No, long flat blade screwdriver....
 
I noticed that the rotor position and the distributor shaft don't line up...Even when I align the slot on the gear, pointing towards #1, I'm stll not leined up with my timing marks.
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JeffreyLee said:
The shaft is engaged on the cam gear, doesn't it need to be lifted up to be re aligned?
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You want the slot to point to #2 cylinder before you engage the gears, then with the twist of the gears, it will end up pointing to #1 cylinder when it fully seats...
 
JeffreyLee said:
I noticed that the rotor position and the distributor shaft don't line up...Even when I align the slot on the gear, pointing towards #1, I'm stll not leined up with my timing marks.
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Some distributors are set up 90° off between the slot and rotor...

If you just keep the shaft where it is, and find TDC, then install the distributor and whereever the rotor points, make that your #1 terminal on the distributor cap... Then follow the firing order around the cap with the wires and you will be ok... Like I described in my first post above... ^^^^

You don't have to have the rotor set up like the factory... Especially if the distributor is 90° off what the factory ones are...
 
Thanks again guys, I didn't know about rotating the distributor gear to point correctly. I'm all lined up properly now. The rotor is pointed down the middle of the engine, but the slot is pointed correctly. Next thing to do is establish plug wire #1 (again, pointing towards #1 cyl?) and then install plugs according to firing order....Yes?
Again, I couldn't have done this project without you.
 
Hi KrazyKuda, I just re-read your reply, You are saying that the #1 plug wire should be located where the rotor points and not based on the slot position.
 
JeffreyLee said:
Hi KrazyKuda, I just re-read your reply, You are saying that the #1 plug wire should be located where the rotor points and not based on the slot position.
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correct. make sure #1 cyl is at TDC on the compression stroke. timing mark should point to 0. find where the rotor is pointing and that is where the #1 plug wire goes.
 
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abodyjoe said:
personally i'd rotate that dist a little to the right so the vac advance is pointing straighter to the right fenderwell.
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What he said.
The most important point has been said several times; the #1 piston has to be at TDC on the compression stroke.
The rotor can be pointing anywhere, you just put #1 plugwire into whatever tower is closest to being above it.
But before you do that, you need to put the Vcan into a decent working relationship, and align the magnetic pick-up to a reluctor vane.
To do that;
starting from TDC-compression, back the crank up CCW from the front, to 10* BTDC. Then push the Vcan all the way CW from the top, to the firewall on the passenger side. Pop the rotor off, Observe the relationship of the reluctor vane to the protruding nub on the magnetic pick-up. Align the NUB, with the nearest vane, by pulling the Vcan towards the rad. Lock it down. Install the rotor and seat it. With a sharpie, index the OUT-side of the distributor body where the rotor is pointing. That will be where #1 plugwire will plug in. Install the cap, and wire the rest in.
If the mark you made is not under a tower, within about 1/3 of the distance between towers, then the rotor may have to be indexed. That's another post.
Start the engine and set the POWER-Timing.

Now, if your rotor is not pointing to the front #1 intake bolt,
this is no big deal, to you.
But any mechanic who sees this when trying to solve a no-start, will jump to the conclusion that it got there by the timing chain having jumped a few teeth.If He's a good mechanic, he'll figure it out pretty quick. But the figuring, costs you money. If he's not a good mechanic, you might return to find the front of your engine scattered all over the workbench..... costing you even more money.
So in the interest of saving you money, it behooves you to put it where the textbooks say to put it. And that procedure has already been detailed.
Good luck
 
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With that offset on the rotor, you want the slot pointing towards the drivers front fender /outer headlight.

There is TDC twice on a 4 stroke. You need to be on the compression stroke, thus the finger over hole test, or pull the driver cover and tunr engine over, watch the intake rocker. When the valve closes the next time your timing mark comes around is TDC compression. Turn it over clockwise when looking at the front of engine.

Reality, the engine doesn't care where the distributor is pointing as long as the wires are in the corresponding holes for correct timing.
 
JeffreyLee said:
Hi KrazyKuda, I just re-read your reply, You are saying that the #1 plug wire should be located where the rotor points and not based on the slot position.
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Yes, use your finger in the #1 spark plug hole to find the compression stroke of #1, then get it to TDC and see where the rotor points... Make that your #1 terminal on the distributor cap and then follow the firing order around the cap in the direction of rotation...
 
Keep it simple @JeffreyLee .

When you feel air pressure pushing your finger from the #1 cylinder that's close to TDC.

Run the spark plug wire from #1 cylinder to the distributor cap and connect to the post of the cap the rotor is at. Then go clockwise 8436572.

The slot in the intermediate shaft doesn't matter (to a point until it causes interference with the vacuum can and other things!).
 
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