S2 multiple timing marks - Solved!

[Richard48Y]

Red S2 has multiple timing marks on the flywheel rather than the single mark portrayed in the manual.
Looks to be at least ten marks.
Performance flywheel or from another engine variation?
Leaves me wondering which mark is actually TDC?
Engine is not simple to turn over incrementally to check at the piston.
And the head is on.

[dakazman]

  Of the three flywheels I have just one mark.
   You will eventually have to turn by hand to set the value clearances but if you did that then you have two alternatives.
  Without gearbox , screwdriver turning the flywheel one tooth at a time , of course with plugs out.
  Gearbox in , one wheel on ground turn the other. I don’t like this because it’s impossible to get exact because you can’t see critical motions. Even with two people you pass thing up.
Dakazman

[jbcollier]

Just use a piston stop.  Turn the engine one way and mark the flywheel where it stops turning.  Then turn the other way and do the same.  TDC is exactly between your two marks.

[dakazman]

 JB,
    What is a piston stop?  I'll give it a try on my engine that's on the stand, after I mount it sideways.
Dakazman

[Richard48Y]

I was hoping this was a known issue to avoid the piston stop hassle.
My only way to safely turn the engine with the suspension off is prying the flywheel.

[TurboFource]

I made one by breaking the ceramic out of a spark plug, welding a nut to it and using a long bolt with the end rounded so it wouldn’t mar the top of the piston

[My S1]

Then there is the old guy method;  remove #1 plug, put your finger over the hole and have your woman crank the engine until the compressed air pops the finger out.

[dakazman]

  Luckily I’ll forgo that process. I put the forward pulley on the crankshaft with a nice bolt for turning the engine. It will come in handy when I plot the cam. The shop gave me a card for an 8 cylinder. 
  I can also do this on my wedge engine as long as the plugs are out for easier turning.
Dakazman

[GavinT]

I've seen a method similar to the one Turbo describes.
'Twas somewhat different in that it used a drilled guide at the top of the spark plug tube on a crossflow head to maintain alignment of the rod. The rod isn't threaded and freely slides up and down in response to the piston movement.

YouTube demo of removing the porcelain from the spark plug.

https://youtu.be/QU-2HQ7NakQ

[Richard48Y]

I have a piston stop.
But working alone crawling under, climbing out from under, checking, repeat until TDC is found, will be annoying.
I've inquired at a Renault enthusiast site which may have an answer.
I may also try the cell-phone camera magnification trick to see if one of the lines is longer than others.
I would expect that either the middle or last line is TDC.

[dakazman]

  This would work, and I might try it myself.
  Anything the would show continuity would work , bringing the contact down slowly would pinpoint it.
   Can’t you use the flywheel bolts to turn? Is the gearbox in?
Dakazman

[Richard48Y]

Yes, gearbox is in.
Not a critical item, it is close enough to start.
Just like to get it done properly.
Knowing which mark is TDC will be useful when I am able to use a timing light.
So far no one at the Renault group has a clue either.

[dakazman]

  So your turning the rear wheels with gearbox in third with one wheel on ground ?
 
  I’m right there with you on the timing light. Still haven’t gotten to it.
Dakazman

[Richard48Y]

Rear suspension is off for cleanup and new mounts.
So the flywheel from underneath is my only way to turn it slowly.

[dakazman]

  Well then it’s time to punt… live to fight another day .
 
  I’m positive you can find some else to do , trust me , some of these so called small jobs takes up a lot of time .  I’ve done a bunch of other things and shelved them . It seems I’m always saying what else can I do .  Keep positive and circle back.
Dakazman