MoparFins

Techical Discussions => Tech- - Engine => Topic started by: attkrlufy on October 05, 2009, 06:11:03 PM

Title: Timing chain line-up
Post by: attkrlufy on October 05, 2009, 06:11:03 PM
I don't think I screwed things up...but I don't think I helped myself, either.  I'm replacing the timing set on my 360 and after removing the harmonic balancer and timing cover I find this is my situation:
 
(http://farm4.static.flickr.com/3436/3985386483_14f45539b8.jpg)
 
If you can see, the timing mark on the cam sprocket is at around 8 o'clock and the timing mark on the crank sprocket is at around 3 o'clock.  I thought I had reached TDC on #1 cyl. but I guess I was wrong.
 
So here's my question.....can I just pull the timing set and then replace it with the replacement set - making sure the timing marks are in the same place, or should I try....somehow.....to rotate the crank 1/4 turn to the L to get the timing marks to line up at 12 o'clock and 6 o'clock respectively?
Title: Timing chain line-up
Post by: Steve on October 05, 2009, 06:59:40 PM
There are two little dots on the two gears.  You have to line them up.  Lower gear points up and upper gear points down.  It's just a little zero.  You need to clean the crud off that one to see them.
 
If you are replacing the chain and gears, you could line them up later.  The 318 and 360 have valve relief
Title: Timing chain line-up
Post by: Stitcherbob on October 05, 2009, 08:12:01 PM
(http://www.moparfins.com/forum/smileys/smiley10.gif) you have to start by lining them up....rotate the crank with the bolt back in the snout until #1 is TDC and you will be sure that everything is right where it is supposed to be (pull all the spark plugs to make it easier)

Title: Timing chain line-up
Post by: firedome on October 06, 2009, 02:45:33 AM
Make sure to check the cover for corrosion holes  - coolant leaking in has been known to happen!

Title: Timing chain line-up
Post by: Stan Paralikis on October 06, 2009, 03:06:08 AM
Quote from: attkrlufy
 
If you can see, the timing mark on the cam sprocket is at around 8 o'clock and the timing mark on the crank sprocket is at around 3 o'clock. 
I'm shocked that it ran at all!
Title: Timing chain line-up
Post by: Steve on October 06, 2009, 06:39:07 AM
It doesn't work that way
Title: Timing chain line-up
Post by: Stan Paralikis on October 06, 2009, 09:08:40 AM
Quote from: POLARACO
It doesn't work that way

What doesn't?
What is "it"?   (http://s65605.gridserver.com/wp-content/uploads/2009/02/bill-clinton1.jpg)
Title: Timing chain line-up
Post by: firedome on October 06, 2009, 10:27:28 AM
"what is it?" That's what Monica said.
Title: Timing chain line-up
Post by: Steve on October 06, 2009, 11:41:06 AM
No she said she needed the Hubble
 
He didn't inhale. . .  She didn't. . . . . . . . .
 
If you spin the engine around enough times. the marks will come back to TDC.  It has to go through the 32 cycles to do so.  Or is it 16.  I forget
Title: Timing chain line-up
Post by: Stitcherbob on October 06, 2009, 03:45:29 PM
remove distributor cap and look for rotor lining up on #1 plug terminal while turning it over.

Title: Timing chain line-up
Post by: attkrlufy on October 06, 2009, 04:12:48 PM
Quote from: Commando1
I'm shocked that it ran at all!
 
Maybe I wasn't clear, sorry.  The engine is timed perfectly fine - I missed TDC on cylinder 1 by a 1/4 turn of the crank (I thought I had it....I guess not  (http://www.moparfins.com/forum/smileys/smiley17.gif)).  My question is:  can I simply pull the two gears AS IS and just replicate where each dot is (8 o'clock and 3 0'clock respectively) when I put the replacement set in, or should I spin the crank to get the timing marks to line up facing each other at 6 and 12 o'clock and then pull 'em?
 
Quote from: POLARACO
If you spin the engine around enough times. the marks will come back to TDC.  It has to go through the 32 cycles to do so.  Or is it 16.  I forget
 
So I can't just spin the crank backwards to get the dots to line up?  Honestly, I don't understand.  If the timing marks line up when both shafts are moving clockwise, why won't they line up going counter-clockwise?  Does it damage the engine somehow, or something?
Title: Timing chain line-up
Post by: Steve on October 06, 2009, 04:57:26 PM
I said that earlier.
 
Yes You can align it after you take the gears off.  If the push rods are still out, it's better.  Take the plugs out too.
Title: Timing chain line-up
Post by: Butch Houghton on October 07, 2009, 05:05:15 AM
You only need to go no more than 2 revolutions to get a timing chain lined up.   They're either right on the first or 180 degrees out,  one more & you would have it.

You do have to make sure it's on the compression stroke though.    You can turn it over with the bolt in & stick your finger in the # 1 plug hole & feel for the compression.  Watch the dots to see if they come up in line.  Or if you want stick the timing cover on with 2 bolts & put the damper back on temporarily to get a visual on exactly where you are while still feeling for compression.

The bottom line is...if you can spin it & the dots DO line up ( take a straightedge & hold it across the bolts for crank & cam to check ) then it probably is really OK & not slipped.   The Cam & crank gears are on keyways & if the dot come up right then everythings still in time & you can change right there.  Using the straightedge if it was off you'd see it right away.  I just prefer to make sure of TDC at the same time but this would work.

And yes you can back it all up & come at it again,    back a good 1/2 revolution to let everything re-set ( take back up the slack in the chain ) & come back to line up.

2 complete revolutions of the engine is 1 cycle ( 720 degrees ) & the cam & distributor run at 1/2 that.