[s-cars] Flywheel TDC mark

[radek at uniserve.com]

Thank you guys, after a lot of searching we found the mark.  It wasn't  
really visible, but you could feel it with the tip of a knife.   
Cleaned it up, put white paint on it, everything is good!

Next question:  does it make sense to change the head gasket if there  
is a slight oil leak from under it in one corner?  It doesn't seem to  
affect the operation, but since we are doing a timing belt, then  
perhaps?
Thanks a lot.

Radek.

> I just did my 95.5s timing belt this weekend.  There were large  
> square pieces >of metal on the flywheel, but they were not the mark.  
>  There was a fairly >faint line on the flywheel at the correct  
> point.  I lined up the marks on the >pulleys on the front first and  
> then checked on the flywheel and was able to >see the mark.

It is actually set up so that the mark is just outside the windows  
when at TDC.

> I believe there is a difference, but it does not look like a  
> documented factory
> change, but rather sloppy work omitting the mark on many of the  
> later engines.
> I don?t even know where to place any blame since I don?t know if the  
> flywheel >is attached at the engine plant or later, but my  
> understanding is the mark is >not made >until the mechanical  
> relationship between #1 cyl TDC is established >with flywheel  
> position since this mark is the most precise.  I can only >surmise  
> that the >worker responsible for this retired without training a  
> replacement.

> IME, the square marks have no place in timing measurements.

> The little oval mark made with a hand stamping tool and hammer that
> seems to be on every rusty flywheel for early models just is not there on
> some later vehicles.  Flywheel changes can account for some since a new
> flywheel won?t have a mark, but others are known original parts.  The timing
> pins for for the crankshaft timing and speed sensors give the most problems
> now by detaching from the flywheel because the attaching welds were weak.

> This causes many to spend some extra time verifying the marks on the front
> of the engine and removing the valve cover to match cam sprocket marks and
> physical piston position.

> Tom

[Hide Quoted Text]
On Tuesday, Oct 27, 2015, at 09:05 AM,radek at uniserve.com wrote:
Is there a difference between early and late models urs4 and urs6?  We
are doing a timing belt job on my son's 1996 and all we can find on
the flywheel are two small square ridges, one a few degrees Before
TDC, the other more or less at TDC.  Meanwhile Bentley says it should
be a notch marking the TDC, consistent with my experience with other
I-5s.  Any clues?  TIA.
I believe there is a difference, but it does not look like a  
documented factory
change, but rather sloppy work omitting the mark on many of the later engines.
I don?t even know where to place any blame since I don?t know if the  
flywheel is
attached at the engine plant or later, but my understanding is the  
mark is not made
until the mechanical relationship between #1 cyl TDC is established  
with flywheel
position since this mark is the most precise.  I can only surmise that  
the worker
responsible for this retired without training a replacement.

IME, the square marks have no place in timing measurements.

The little oval mark made with a hand stamping tool and hammer that
seems to be on every rusty flywheel for early models just is not there on
some later vehicles.  Flywheel changes can account for some since a new
flywheel won?t have a mark, but others are known original parts.  The timing
pins for for the crankshaft timing and speed sensors give the most problems
now by detaching from the flywheel because the attaching welds were weak.

This causes many to spend some extra time verifying the marks on the front
of the engine and removing the valve cover to match cam sprocket marks and
physical piston position.

Tom

[Hide Quoted Text]
On Tuesday, Oct 27, 2015, at 09:05 AM,radek at uniserve.com wrote:
Is there a difference between early and late models urs4 and urs6?  We
are doing a timing belt job on my son's 1996 and all we can find on
the flywheel are two small square ridges, one a few degrees Before
TDC, the other more or less at TDC.  Meanwhile Bentley says it should
be a notch marking the TDC, consistent with my experience with other
I-5s.  Any clues?  TIA.