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Trying to "find" my timing marks

MetalSteve

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I have a 72 Plym with its original 318...

The engine has been rebuilt but neither the timing cover
nor the harmonic balancer was changed. The timing marks are clear and visible
(No gunk or residue in the mark)

Was trying to time the engine and the marks are no where to be "found" using two
different timing lights. The engine is running so-so and needs to be timed but
I do not want to start guessing so to speak. Car is stuttering around 40-55 mph too...

The engine has a mild cam and Edelbrock Performer 1406 but nothing crazy.
 
Clamps on the right cylinder? :popcorn2:
 
Make sure the harmonic balancer did not shift. Set it to TDC mechanically and see where it is at.
 
There will be a slot/line on the harmonic balancer. Basic "white out" on that line helps a lot
 
Make sure the harmonic balancer did not shift. Set it to TDC mechanically and see where it is at.
Can't really get to a point to pop the head off... Trying to set the timing better in a car port with little tools avail at the moment...
 
Got ya easy way to do it is pull #1 plug, put your finger over the hole and when it pops off while rotating the engine your close. The balancers do slip on the rubber, just something to check. Also are you using a dial back style timing light? They are usually off.
 
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Balancers do slip over time causing the groove not to line up properly. Years ago I made a piston stop tool using a non foul adaptor I got from a parts store. 14mm 3/4" reach, looks like the steel portion of the plug. I put a piece of all thread in it with about an inch sticking out on the piston side and same on the plug wire side. One nut on each end to hold it tight. Pull all of your spark plugs out, thread this into the #1 hole finger tight. Rotate the crank by hand clockwise. When it stops, mark the balancer where 0 is on the cover. Rotate it counter clockwise till it stops again. Remark the balancer. Halfway in between the marks is where your outer balancer ring mark should be. If not, replace.
 
Got ya easy way to do it is pull #1 plug, put your finger over the hole and when it pops off while rotating the engine your close. The balancers do slip on the rubber, just something to check. Also are you using a dial back style timing light? They are usually off.
One was a dial type, the other was a digital. Didn't "see" the marks with either one.
 
Hard to believe that the balancer has slipped that much. Vac adv disconnected. Recheck your methods.
 
It’s easier to verify TDC with two people.
One to turn the engine with a breaker bar, the other to look in the spark plug hole with a good flashlight.

Once you get the piston close enough to TDC to see it thru the plug hole, on a 318 it should be pretty easy to get real close to TDC by using something like a long thin screwdriver in the hole while the other person runs the breaker bar.
When you’re close, you’d turn the crank back and forth to zero in on the center.
There will be about a 5-8 degree range of rotation where the piston barely moves at all.
The center of that range will get you (more than)close enough to see if the outer ring of the damper has slipped.
Once you’ve “zeroed out” the screw driver travel, the line on the damper should be very close to the TDC mark on the cover.
If it isn’t, the ring has slipped……..which is not at all uncommon with a 50 year old damper.

If the marks don’t line up, the other possibility is that the damper was swapped at a previous point, with one that would be used with a different timing cover.

To check the timing, if the original marks don’t line up…….make a new mark on the damper that’s in line with the TDC mark on the cover, and check the timing using your newly confirmed line on the damper.

And yes, vacuum advance disconnected.
 
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