Rotor position at TDC

[JayJay]

Originally Posted by Y-Blockhead

Nope. The slot on the bottom of the distributor is offset. The distributor will only drop down into the slot in one position. If he is 180° off he will have to loosen the rotor and turn just the rotor 180° to line up with TDC on #1 compression stroke. No need to lift the distributor.

I believe OP stated he was using the NuRex tool. If so it's pretty much foolproof. At #1 TDC compression you loosen the distributor cam, rotate the cam a couple of times, stop with the tool resting against the #4 terminal, then tighten the cam.

[Dan McEachern]

Easy way to find your compression stroke is to just put a finger over the spark plug hole while you are cranking the engine over and when you feel pressure increasing, you're there. Now look in the hole as the piston comes up, and start using the timing pin. When the pin drops in the detent, stop and set your point cam.

[J Franklin]

Dan, Well said it really is that easy!

[katy]

Originally Posted by fried okra

I am visibly at TDC on #1 piston and get a slight motion on the timing pin against the timing gear but it does not readily go into the timing gear hole. I assume the timing pin is just too tight a fit.

Try using a stubby phillips screwdriver in place of the pin.

[Y-Blockhead]

Originally Posted by ModelA29

You can lift it anywhere and turn it 180 degrees so it drops back into the drive slot. When the pin is in the dimple it's always at TDC.

Originally Posted by Y-Blockhead

Nope. The slot on the bottom of the distributor is offset. The distributor will only drop down into the slot in one position. If he is 180° off he will have to loosen the rotor and turn just the rotor 180° to line up with TDC on #1 compression stroke. No need to lift the distributor.

[QUOTE=JayJay;2293572]I believe OP stated he was using the NuRex tool.

JayJay, Please read what I was referring too. Regardless if you use the Nurex tool or not, you can not just lift the distributor and turn it 180°!

[JayJay]

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[QUOTE=Y-Blockhead;2293610]

Originally Posted by JayJay

I believe OP stated he was using the NuRex tool.

JayJay, Please read what I was referring too. Regardless if you use the Nurex tool or not, you can not just lift the distributor and turn it 180°!

YB - I agree, and wasn’t trying to imply otherwise. If the distributor is properly in the head and the rotor is pointing 180 degrees out, then likely you have the exhaust stroke, not the compression stroke.

[Afordman31]

Some of the cam gears don't have a very deep dimple. After I locate the dimple I use a small mirror and flashlight to see if the dimple is perfectly in line with the pin hole.
Alway's remember to install and snug the pin at this point.

[fried okra]

Good input group, thx....am making progress here.

[Bruce of MN]

I have left the pin there too many times, but luckily it fell to under the radiator, so I painted it gold to try to remember to screw it where it belongs.

[Synchro909]

Originally Posted by Afordman31

Some of the cam gears don't have a very deep dimple. After I locate the dimple I use a small mirror and flashlight to see if the dimple is perfectly in line with the pin hole.
Alway's remember to install and snug the pin at this point.

I know many people think those degree scales that go on the front of the engine are an unnecessary gizmo but with one fitted, you can pretty much go straight to TDC once you have done it once and marked the pulley.
I found the scale VERY useful timing my diamond B engine fitted with an A distributor. I found the dimple using the pin (and B timing cover) but I didn't mark the pulley at zero. I marked it at 19° advanced, then turned the motor back to where that mark was at the zero mark (the engine was now at TDC) and set the timing in the usual Model A way. Perfect!

[Y-Blockhead]

Originally Posted by Synchro909

I know many people think those degree scales that go on the front of the engine are an unnecessary gizmo but with one fitted, you can pretty much go straight to TDC once you have done it once and marked the pulley.

As Synchro state, once marked it makes #1 TDC easy to find.

I actually set my timing a little after TDC because I have a Nurex Auto Timer and I want to limit total timing to ~30° BTDC.

[Bruce of MN]

I’ve done the same, but my pulley flange is too narrow for a mark, so I filed a small notch.

[Bob Bidonde]

Y-Blockhead, is that sexy looking fan belt noisy?

[john charlton]

Years ago I forgot to refit the timing pin . After a short drive the engine was well covered in oil . I was amazed at how much oil had come out of that tiny hole !!! The pin was lost on the road somewhere .

John in sunny Chandler AZ .

[Y-Blockhead]

Originally Posted by Bob Bidonde

Y-Blockhead, is that sexy looking fan belt noisy?

Bob, No the segmented belt is not noisy. They are directional tho so you have to ensure they are installed corectly. I use them on my table saw as well.

I originally installed it because with the thicker Murrey Horn Harmonic Balancer I could not fit the stock type belt between to pulley and the frame.

An added bonus is that they can be shortened so you can bypass your water pump or generator if you lose a bearing while out on the road. Until you can get to a place to repair or change them safely. (I have never had to test this tho).