74 260z distributor on wrong ??

[Zed Head]

One side is smaller.  That's why the distributor shaft can only install one way.

[Shawninvancouver]

Yes zed. I know. So when I rotate engine one revolution the smaller half is on other side. But still at 1:35 position. 

[siteunseen]

You have a 240/260 pedistal and a 280 distributor. I wonder is that compatible components?

Here's what you have.

 

Heres a 280 distributor . The timing plate and pedestal are different.

 

[Racer X]

25 minutes ago, Shawninvancouver said:

Yes zed. I know. So when I rotate engine one revolution the smaller half is on other side. But still at 1:35 position. 

Before you rotated the engine one revolution, was it at top dead center?

[Zed Head]

21 minutes ago, Shawninvancouver said:

Yes zed. I know. So when I rotate engine one revolution the smaller half is on other side. But still at 1:35 position. 

One rotation puts the engine on the opposite cycle or stroke.  It's a four cycle engine.  Compression (up), combustion (down), exhaust (up), intake (down).  There are two cycles per revolution.  The reason the small side needs to point a certain way is so that you can get the rotor in the distributor to point at the #1 cylinder on the compression stroke so that the spark will light the fire.  If it's pointed the other way the spark happens during the exhaust stroke, where nothing will happen.

https://en.wikipedia.org/wiki/Four-stroke_engine

[Racer X]

34 minutes ago, Shawninvancouver said:

 

 

 

 

In this picture, is the piston at #1 top dead center on the compression stroke?

Oh, and one picture is enough. We don’t need to see 4 pictures of the same thing.

 

Edited June 9, 2021 by Racer X

[Shawninvancouver]

19 minutes ago, Zed Head said:

One rotation puts the engine on the opposite cycle or stroke.  It's a four cycle engine.  Compression (up), combustion (down), exhaust (up), intake (down).  There are two cycles per revolution.  The reason the small side needs to point a certain way is so that you can get the rotor in the distributor to point at the #1 cylinder on the compression stroke so that the spark will light the fire.  If it's pointed the other way the spark happens during the exhaust stroke, where nothing will happen.

https://en.wikipedia.org/wiki/Four-stroke_engine

Ohhhh shoot.  That I did not know.   I just assumed there were two strokes. Up and down.  So I tried once. Then did one revolution and tried again.  I need to do this with valve cover off.   That helped me out a bunch.  Thanks for being patient.  

[Shawninvancouver]

20 minutes ago, Racer X said:

In this picture, is the piston at #1 top dead center on the compression stroke?

Oh, and one picture is enough. We don’t need to see 4 pictures of the same thing.

 

That I don’t know.  I need to do it with valve cover off.  Abs I look for piston up and cam lobes pointing up. ?? That’s all I need to see for tdc? Or do I also need to look at valves. ??

[Racer X]

2 minutes ago, Shawninvancouver said:

Ohhhh shoot.  That I did not know.   I just assumed there were two strokes. Up and down.  So I tried once. Then did one revolution and tried again.  I need to do this with valve cover off.   That helped me out a bunch.  Thanks for being patient.  

Suck, squeeze, bang, blow.

Four events.

Four strokes.

Read the stuff at the link.

https://en.m.wikipedia.org/wiki/Four-stroke_engine

 

 

[Racer X]

3 minutes ago, Shawninvancouver said:

That I don’t know.  I need to do it with valve cover off.  Abs I look for piston up and cam lobes pointing up. ?? That’s all I need to see for tdc? Or do I also need to look at valves. ??

You can see the cam lobes through the oil fill hole.

[Shawninvancouver]

Ya. But can’t see piston up.  I’m just gonna take cover off.  I need to get to the bottom of this.  

[Patcon]

You need to remove the spark plug to check if the piston is all the way up