Topic: Breaker points and timing

[stereosilence]

I'm going through to try to get everything set up before I start tinkering with the carbs. I am following my Clymer manual. It says to rotate the crankshaft "until the points for No 1 and No. 4 cylinders are fully open." The picture shows that TF1-4 should be lined up. However, I notice that the spot where the points are fully open is somewhere about halfway between the 1-4 and 2-3 notches. Is this correct? I set the clearance to .004mm at the notches but I am confused by Clymer.

Also, what is the significance of the ignition timing (that you have to use the light to set)?

[lucky]

Where to start.
OK...

First you need to take the slack (if any) out of the cam chain.
Bottom of page #48 Clymer's.

Then to adjust the valves use a volt ohm meter instead of a light.
If you use a 12V light it has some resistance and the timeing will not be as accurate as using a volt/ohm meter set on the ohms X 1000 scale.

Take the spark plugs out to set the valves so that turning the engine over is much easier.

Refer to the bottom of page 46 right side. Just follow the directions.

Also: after adjusting the intake valve which is rarely off, check it with a .003 gauge and if the .003 goes in then it means it is loose because only the .002 should fit.

For the exhaust which is more likely to be off check it with a .004 thickness gauge.
If a .004 goes in then it is loose too and needs adjustment to get it back to .003

The danger is if the valves are too tight.

[stereosilence]

I have done the cam chain and valves previously. I tried using my ohmmeter but it was freaking out a bit, but the light seemed to do the trick.

Anyway, I don't think it was off much. I don't expect much difference in the operation. I think I need to properly set my carbs (and make them a bit more lean while I'm at it).

I deduced the ignition timing is to make sure the plugs fire at the right moment according to the position of the valves. The breaker points are what apply the spark to the plugs at the right moment (hence the light coming on right when you hit top dead center).

[Spanner 1]

Huh ?... the question was about setting the ignition timing

First turn the crankshaft until the 'F' 1-4 mark lines-up with the mark in the points plate 'window'... now turn a further 90 deg. past the 'F' mark, this is the highest bump on the cam and where you set the point gap at 14 thou. for 1 and 4 points. Next turn to 'F' mark for 2-3 and continue 90 deg. past, set 2-3 points at 14 thou.....next is the actual timing, achieved by adjusting the points plate left or right in it's slots to achieve the points opening at the F mark for each point set. The main plate sets 1-4 points ( lefthand set ). Options are ohm meter or 12v test light... I'm stopping here 'cos 100's of explanations of how to do timing, better than I can explain now  ... read all about it....

[stereosilence]

So you are saying the gap should be .0014" at the widest possible? I set it to that gap at TF1-4. I don't see how you can accurately measure the exact spot where the gap is at its maximum.

[stereosilence]

Sure enough. I checked one of the maintenance manuals (what I should have done in the first place instead of following Clymer).

[dave500]

I don't see how you can accurately measure the exact spot where the gap is at its maximum.

this is where a dwell meter comes in handy.

[Spanner 1]

You don't look at the gap, or worry about it !... just turn the points cam 90 deg. past the F mark ( for the points your working with ) and then set the gap @ 14 thou. Done  .. Repeat for the other set.