Simple yet important engine timing questions

[2wrench]

1974 TR6

Which way does the engine turn, facing it at the front of
the car looking onto the degree marks of the damper, clockwise?

What is the recommended degree mark setting to set the
damper, such as: 4 degrees ATDC, for tune-up?

If the engine rotates clockwise, all degree marks to the
left of the 0 degree mark are properly referred to as
ATDC. Is this correct?

Check out my rebuilt damper. It has two large markings
on it. I believe one to be at TDC. The other is four
degrees to the left of it. Did a previous owner remark
the 0 degree TDC marking, or were they placing another
larger mark at 4 degrees away in order to see that mark
easier for timing? Your best deduction apprecited.

Oh, one more thing: After bolting on the timing chain
cover, how deep into the cover do I press the oil seal
that slides onto the crank and presses into the cover?
Does it go flush with the cover's interior oil seal or
do I leave 1/16 to 1/8 inch protruding?

Thanks,

 

[2wrench]

And, oh, Brosky's damper looked way better than
mine. They didn't paint the numbers and degree
marks on mine real pretty like his. So I tried to do
this myself. Got the things white. Now if I can
only figure how to paint the topside black without
getting black paint down in the degree marks and
numbers....or I could forget about that, suppose.

 

[mikespain]

HI the engine turns clockwise looking from the front,the 4 degree mark is the ignition timing mark-4 degrees before top dead center(BTDC)the oilseal should be fitted before the timing cover goes on and fitted until flush with the outer edge of the cover.

 

[PeterK]

To remove the white from the flat surface, wrap a piece of cloth tightly around a block of wood, dampen the cloth with paint thinner, then buff off the excess white.

The seal goes in with the open side (lip) facing the engine. The lip needs to ride on the smooth nose of the crank to make a seal.

 

[2wrench]

For clarification: Is the extra line
four degrees BTDC or is it four degrees ATDC.

 

[Roger]

If I assume that the front of the damper is to the left, crank to the right, it's 4 deg ATDC. The damper will have rotated 4 deg before the mark comes to the top.

 

[RomanH]

The second line is 4 deg. AFTER TOP DEAD CENTER.

 

[2wrench]

Stock setting to tune a '74 TR6 timing. Is the
timing supposed to be 4 degrees BTDC?

If it is, then it seems a previous owner might have
slightly modified my damper.

My damper's pointer now points directly to the
extra four degree after top dead center mark. If specs
call to time engine four degrees BTDC, then that would
mean that I could see where to set the timing; it would
be set using the original, large and easy to read
TDC marking. Very interesting; very cool, if true.

My Bently Manual kind of confused me. Said my engine
rotates in an anticlockwise direction. Has to be if
you're looking at it from the rear/driver's cab area.
Who works on their engine from the interior cab? Freaked
me out.

 

[poolboy]

2, if you are going to use a timing light after you do your static timing, it might be a good idea to really make the 10- 14 degree BTDC marks distinctive. You will probably be in that neighborhood at idle with the vacuum retard dis connected.

 

[Guest]

You are sure your damper hasn't slipped?
Did you get it rebuilt?

 

[2wrench]

Damper was rebuilt. Points to four degrees ATDC
though. My engine has been balanced, etc. I don't
want to get all excited about it and try to replace,
etc. I could still use it, knowing this is my new
TDC line, couldn't I? I do believe this was the
way it was oriented when the rebuilder got it, so I
couldn't complain.

 

[RomanH]

2wrench, your damper looks exactly like mine in my '74.
The stock timing for a '74 TR 6 is 4 deg AFTER TOP DEAD CENTER. This is the emission standard set up for that year. The only proper way to adjust the timing to achieve 4 deg after is to use a timing light and have the vacuum retard line hooked up. If you disconnect and plug the vacuum line then set the timing to 4 deg after when you reconnect the line the timing will be somewhere around 10 deg after and will not run well if at all.

"My Bently Manual kind of confused me. Said my engine
rotates in an anticlockwise direction. Has to be if
you're looking at it from the rear/driver's cab area.
Who works on their engine from the interior cab? Freaked
me out."

Thats the convention. Crank rotation is always described as one looks at the output side. In the case of a car from the point of view of the transmission forward.