Right, at #1 the crank is 12 and cam is 12.
Can engine run with timing 180 off?
Thread Starter
Drifting
Joined: Dec 2004
Posts: 1,714
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From: Austin Texas
Can engine run with timing 180 off?
My small block was running great. So I decided to do a cam change and tear it apart. I wanted to check the timing marks from the previous owners build. So I did the following.
1. Marked #1 plug on dist. base and removed cap.
2. Rotated crank until rotor pointed at #1 (confirmed compression) then put the mark on the balancer at zero on the timing tab.
3. Removed the timing chain cover.
Now at this point I was expecting to find the crank dot at 12 o'clock and the cam dot at 6 o'clock. That did not happen.
The crank was at 12 o'clock AND them cam sprocket was also at 12 o'clock.
When I line them up at 12 and 6 the rotor points at #6.
Is this possible?
I am confused
1. Marked #1 plug on dist. base and removed cap.
2. Rotated crank until rotor pointed at #1 (confirmed compression) then put the mark on the balancer at zero on the timing tab.
3. Removed the timing chain cover.
Now at this point I was expecting to find the crank dot at 12 o'clock and the cam dot at 6 o'clock. That did not happen.
The crank was at 12 o'clock AND them cam sprocket was also at 12 o'clock.
When I line them up at 12 and 6 the rotor points at #6.
Is this possible?
I am confused
Thread Starter
Drifting
Joined: Dec 2004
Posts: 1,714
Likes: 42
From: Austin Texas
What am I missing here?
I just don't understand because the cam sprocket is keyed to only go one way.
Here is a better question. When the dots are at 12 and 6, where does the rotor point? mine points at #6 plug
I just don't understand because the cam sprocket is keyed to only go one way.
Here is a better question. When the dots are at 12 and 6, where does the rotor point? mine points at #6 plug
Last edited by johnt365; Mar 12, 2011 at 08:44 AM.
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From: Dayton, Ohio
edit-removed part of my post, it was confusing and I said 180 when I should have said 360 and I misread what the OP was after.
Mike Ward covered it.
Last edited by ...Roger...; Mar 12, 2011 at 10:52 AM.
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That's the way it's supposed to be. Many people make the mistake of thinking that #1 firing is with the dots pointed at each other.
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Thread Starter
Drifting
Joined: Dec 2004
Posts: 1,714
Likes: 42
From: Austin Texas
Okay, just so I can understand.
Dot to dot is TDC but NOT the compression stroke. To time the engine I need to rotate it 180 so that its crank 12 o'clock and cam 12 o'clock and that will be TDC on the compression stroke.
I was about to be "one of those people"
Dot to dot is TDC but NOT the compression stroke. To time the engine I need to rotate it 180 so that its crank 12 o'clock and cam 12 o'clock and that will be TDC on the compression stroke.
I was about to be "one of those people"
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