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This is on a 250 Monza. After replacing the seal behind the points, I'm confused about whether I'm correctly lining up the timing marks. This is the situation:

1. The engine is at TDC on a compression stroke.
2. The pair of marks on the bevel gears in the head are lined up.
3. The pair of marks on the bevel gears at the bottom of the towershaft are lined up.
4. The integral pinion on the crankshaft doesn't seem to have an inscribed mark on it, instead it has a white paint mark on it, which is now at about 5 o'clock as I look at it.
5. The large pinion gear driving the oil pump has 2 marks on it, about 60 degrees apart. One of these is lined up with the white paint mark on the integral pinion. The other mark is lined up with the single mark on the smaller pinion gear that drives the points.
6. In this position, the drive at the end of the points shaft, the part that engages in the auto advance unit, is vertical.

Is this the correct timing?

I'm sorry if this has been covered lots of times. I've looked in all 3 of manuals and searched this site and the web, and can't quite find the information I'm looking for.

Thanks in advance.

[quote= cooperplace ...
" I'm confused about whether I'm correctly lining up the timing marks.
The pair of marks on the bevel gears in the head are lined up.
The pair of marks on the bevel gears at the bottom of the towershaft are lined up. "

____ Your bevel-gear timing is CERTAINLY correct.



" The integral pinion on the crankshaft doesn't seem to have an inscribed mark on it, instead it has a white paint mark on it, which is now at about 5 o'clock as I look at it. "

____ The paint often fills-in the timing-dots and-thus tends to obscure their otherwise quite-notable existence.
__ The position where you've found the white-marked tooth located at, is consistent with where the timing-dot should be.



" One of these is lined up with the white paint mark on the integral pinion. The other mark is lined up with the single mark on the smaller pinion gear that drives the points. "

____ That should be correct.



" the drive at the end of the points shaft, "

____ I assume you must mean the 'male-slot' -("drive") rather at the base (not "end") of the points-shaft ?



" the part that engages in the auto advance unit, is vertical.
Is this the correct timing? "

____ Once you go-ahead & install the AAU in the one position which will cause the points-cam to position it's lobe-ramp so that the points have just-become pretty-much fully opened,, then yes, that's the 'correct' timing !



" I'm sorry if this has been covered lots of times. "

____ Indeed it has been covered at-least twice before.



I've
searched this site
and can't quite find the information I'm looking for. "

____ Too-bad we don't have a tree-structured thread-topic GUIDE set-up in place, (as only I've suggested), where you could've reasonably quickly homed-in on most-any such subject-matter. - (Such-as these two related thread-posts... viewtopic.php?f=3&t=1833&p=13588&#p13588 ; viewtopic.php?f=3&t=248&p=1539&#p1539 .)


Dukaddy-DUKEs,
-Bob

DewCatTea-Bob wrote:
I've
searched this site
and can't quite find the information I'm looking for. "

____ Too-bad we don't have a tree-structured topic-guide set-up in place, (as only I've suggested), where you could've reasonably quickly homed-in on most-any such subject-matter.

Nice idea in some ways, Bob.
But I don't think it's so bad to go over old topics. People come and go, details get forgotten.
An forum is a good place to look for "instant" info. They've got me out of trouble many times.

[quote= Jordan ...
" But I don't think it's so bad to go over old topics. "

____ Well, that's actually just what a 'tree-structured' thread-directory would be meant to help do ! ... And that's allow searchers to branch-out directly-towards just the particular topic-matter which they wish to find already-established thread-posts covering same (or closely related) stuff they seek.



" An forum is a good place to look for "instant" info. "

____ Yes but, waiting for a rather direct-response can quite possibly take considerably longer than directing 'yourself' to already long-established thread-posts which have previously covered the same question-topics before, ALREADY !
So WHY-not include such handy convenience for searchers to take advantage-of, (rather than be stuck with just our near useless search-engine [which tends to ALSO include everything-else under the sun, moon, & stars along-with just-what ya WANT to find!]) ?
__ I-myself would've gone-ahead & implemented the tree-style directory,, but (as it should be), only Jim-himself has the capability to touch those higher-order w.site feature-alterations.
It seems that no-one other than myself sees the GREAT-advantage of my-idea. (?)


Forum-Cheers,
-Bob

Sorry to start off a firestorm of controversy re searching, but I really appreciate all the great advice. Thank you everyone.

[quote= cooperplace ...
" Sorry to start off a firestorm of controversy re searching, "

____ It's certainly unlikely to be anything so tense as a "firestorm" ! _ In-fact if it weren't for Jordan's use of the word "But", it wouldn't seem controversial at-all,, as he really seems to be in general agreement, (for the most-part, at-least).


Hopeful-Cheers,
-Bob

Yes indeed - easily searchable old messages would be a good thing, alongside the normal banter.

Cooperplace,

It would be great if you could include a photo for each of the condition you're listing.


-Adrian

DewCatTea-Bob wrote:[quote= cooperplace ...

____ Once you go-ahead & install the AAU in the one position which will cause the points-cam to position it's lobe-ramp so that the points have just-become pretty-much fully opened,, then yes, that's the 'correct' timing !


Dukaddy-DUKEs,
-Bob

this is the one thing that still isn't clear. And yes, i have read the other long thread on this. The AUU can be installed in one of two positions. One of these positions the corner, the opening edge, of the lobe, at 2 o'clock. The other has the bulk of the lobe facing to the right. SO it seems to me that both positions fit the descriptions given for the correct position.

If it's all correct apart from the 2 possible positions for the AAU, it's just a matter of seeing when the points are just at the point of opening.
That is a little different to how Bob described it (fully open).
You need to take into account the direction of rotation, otherwise you might use the wrong side of the cam ramp.
There's also variation due to the movable advance range, but it's a lot less than 180 degrees, so shouldn't be a problem.