The tension of the belt is important from the exhaust cam down to the crank. Take a look at this lot, it may help.

Here’s the last bit.

thanks yes seen that - s/be 3/4" and currently it's less than that, which it wasn't before all this, so that's where the "slippage" has gone. 

I may have found a source for that manual.. we'll see

does that manual show a TDC marker on the block for the crank to match to?

No, it doesn’t. I looked on mine just now and can’t see anything on the front cover- saying that, there is so much going on down there it’s impossible to see!

The crank pulley is keyed and it matches up to the auxiliary shaft marks. There is another section in the book(!) describing it as per the pics.

note the bit about the jackshaft alignment 

1 hour ago, Nigel Blandin said:

there is so much going on down there it’s impossible to see!

exactly

ok I have to find jackshaft - I thought that was for the dizzy..

and 

auxiliary shaft - I have seen a mark that looks like an alignment mark on the big wheel behind the crank sprocket.

I'll look at this again tomorrow (my head is asleep)

thanks

p.s. if that's the Haynes manual.. is it? you can just quote page numbers...

how do you loosen the tensioner? working down there is practically impossible

Jackshaft is the auxiliary shaft. It does drive the distributor.

It’s still the Ford workshop manual.

use as socket and spanner to adjust the tensioner as per the picture.

Distributor timing.

have you got an instruction in there about using this lock tool? 

That is not the locking tool Anthony, it is the lock tabs for the X-flow cam sprocket (or in your case the jack shaft sprocket).  If you look at pic 42.38 on page 33 of the Haynes manual you will see it

I need to know how to release the tensioner - indeed where it is, it looks like very low down; I'll add a couple of pics here in a very soon moment

pics show how I have locked the cams (noted where their TDC alignment marks align) and the other piv what I think is the tensioner, with what looks like the only nut available to undo, except wait a minute that nut is the alty holder nut..

ok so belay that, just looked back and seen your image from the manual as here:

any idea what sizes those are? I'be been through both metric and imperial and failed to find so far. I will search again, but tea required..

so, apres tea, I found the outer lock nut is 11/16" spanner (sockets too shallow) and was so tight I tapped it with a lump hammer. Then I found the big inner nut turns with my fingers alone. However, it doe snot turn far and shows how the tightening works. I think. It seems not possible to loosen the belt a lot, only enough to be able to dismount it from the tensioner sprocket gain with my fingers, leaving  the belt loose everywhere thus (next pic) 

so this just leaves the final "shortest way" turn of the crank to TDC; which I (happen to) know is clockwise about 20 degrees. 

and when I put back the belt I have to make sure all the slack is in the run from the exhaust (right side) cam down to the idler pulley, and ultimately 3/4" of play exactly.

Ugh. I need the slack on the right but the tensioner works on the left. great...

I have no experience of these engines (only the X-flow) so possibly someone with knowledge can comment but I would be puzzled as to why the cam pullies are not in the orientation shown in the manual (wrt the bosses) although the timing marks are lined up - does it matter?

The tensioner is circled with the large nut ,1 and small nut, 2 indicated.

are you at tdc on number 1? Let me check where mine sit at that position.

Good evening AndrewE and Nigel, thanks for your input. Regards the alignment marks it seems they are correct (as checked to the position of the cams/valves) in so far as the cams are ready to fire on no 1, or at least they would be if the crank was also in alignment. Which it isn't/ or maybe (BIG maybe) it now is. I await judgement ... and that judgement is it is now ok, being just one rib out would mean a correction of half a rib which is not possible given we do not have verniers. So the next step is to set the tensioner to the 3/4" play on the exhaust cam sprocket to idler pulley (what is that for?) - I feel like this should be trivial, but nothing at all has been so far.

Note: during this second attempt I found the belt gets jammed between the idler pulley and the large cam pulley and I had to put my hand underneath the engine to grasp the belt and pull it free/through. Not being aware if this may be why in my first attempt I made it worse.

The tensioner I find very strange, it has very little give in it and the amount of force I am using to mount the belt (twice now, first time I made it worse) is disconcerting to say the least. Once the locknut is released with 11/16ths spanner the big nut seems to accept adjustment with my fingers alone. I didn't need a second spanner, just gave it a sharp tap.

In my latest (2nd) attempt I clamped the belt to the cam sprockets so I was only adjusting the crank sprocket. I won't bore you with the failure pictures (I made it worse) and will just add the current state of play. Each try is taking me about an hour. I thought it would be dead easy. It's not.

Pictures : The pic of the rotor lets me know the firing position (previously established), the pic of the cams lets those who speak camshaft the same thing (THIS is the help I am relying on, be stuffed without it), I hope and the pic showing the sprockets shows they are now very close; possibly even close enough that the tensioner when adjusted MIGHT take up the difference.

3rd belt attempt, this time even better; what I did different was manage the transition between the idler pulley and the large crank pulley working from underneath the car. 

I can't get the belt tension to 3/4", more like 1/2" so I will return to it later.

Here are the pics showing dizzy rotor (firing position), cams and sprocket alignment markers:

maybe the belt needs pushing more on to the sprockets.

So, 6 degrees BTDC is I gather and vaguely recall set using the distributor; so undo its clamp and twist until the strobe light indicates 6 degrees before top dead centre. 

Now the, I have not altered the cams at all, nor the dizzy and the crank I have "merely" returned to where it was in the first place. Styrikes me that means no need to move the dizzy as it will still be set as it always was, which I would like to think is 6 deg btdc.

One thing perplexing me is there is no 6 degrees mark on the diagram above which looks like 3, 10,18 and 20. I suppose given when I have a working engine I will be using Gunsons Colortune on all four cylinders (simultaneously) the dizzy timing becomes a variable I can tune. 

Need to look in the book - manual pages welcome Nigel s.v.p and Andrew any references? 

I found what looks like the workshop manual still (or edited/adopted) available from Wilcox who I will call tomorrow. edit nope, they are away until September so sent an email.

I found this 

www.britishcarforum.com/community/threads/setting-static-timing-with-pertronix-ignitor.44799/

Quote

Works just like static timing with points. Note, however, that you need to apply power to the red lead of the pertronix ignitor unit while doing this, whether that be via the ignition key turned with the harness all wired up, or a 12V source applied to that lead.
NOTE: I heard something about not leaving power applied to the ignitor with the engine running. Please do this at your own risk, unless someone can step in and correct this technique! I simply applied power for 10 seconds or so, just enough to set the timing, and removed it. Seemed to work for me and not damage anything.
Here's the setup:
- If your harness is not hooked up (i.e., bare distributor with nothing connected), apply 12 V to the red ignitor lead (in which case the wiring harness should NOT be connected to the coil). If your harness is hooked up, turn the key in the ignition to apply power to the ignitor.
- Connect one side of a test lamp to the negative ignitor lead (disconnected from coil... note the red ignitor lead can be left on the coil or disconnected... I found the coil terminal a convenient place to apply 12V to all the leads)
- Ground the test lamp and 12V supply (if applicable) to engine ground.
- Turn timing wheel to static timing point (4deg BTDC in my case, varies with distributor, look up in Bentley)
- Rotate distributor until the light just turns out, and clamp the distributor down. Timing should be close enough to enable the engine to run.
Troubleshooting for novices like myself:
- Be sure the distributor rotor points toward the number one cylinder plug wire when cylinder one is near TDC, transitioning between compression and combustion stroke. You can check this by making sure the rotor points to the #1 plug wire when the valves for cylinder six are both in motion. If it's pointing at the #6 cylinder, take the distributor out, rotate the shaft 180 degrees, and reinstall.
- If the timing light never lights, and you had your distributor drive gear out for a rebuild, for example, your drive gear may be off by a tooth. Try taking the distributor rotational clamp bolt out, and rotating the distributor beyond the range the bolt normally allows. If the light lights, then take the distributor drive gear out and rotate it by a tooth (or however much you need) to get it back in the range allowed by the clamp bolt.
Any corrections or additions welcome!

with thanks to mtribe in 2008 

I think what I will do is see if it starts "as is". then explore the strobe, see if that identifies any block mark lining up with the crank pulley marks.

and I can do this test BEFORE I put the carbs back on, so if I end up changing the ignition again it will be easy.

So, put it all back together and turned the starter: BANG. That's it. One backfire. 

Anyway I think it's because I have installed a different electronic ignitor and I should re install the original to rule out timing differences to see if she starts. 

SPRINGS in the Carbs

I have also replaced the huge central return spring between the two carbs. Upon bending 90 degrees the bit that pokes through the point where the accelerator cable connects, which took a lot of force, it bent nicely without breaking. What I mean is the old one broke and the new one did not upon being bent said 90 degrees. I think this demonstrates metal fatigue of several decades was in play, so again like all the other springs I have replaced I think a degree of flexibility is now renewed in to the mechanism. It is subtle, this " old springs " matter. Previously I have thought of them as less springy because in all cases they have been stretched longer than the new ones. Now it seems the metal itself must be more brittle (hence less springy as well) so that's two elements of less springiness. It will be nice to see if this improves the feel when driving it, I imagine as regards responsiveness and perhaps less "jerky" on the pedal. Shame I can't easily replace all my own springy bits 😉

morning all.

Anthony

ok so despite high hopes not much progress. It seems e v e r y t h i n g is correctly lined up and all that can remain is setting the distributor exactly right.

However, not had any luck with that so far. Next step is to use a timing strobe pointed at the crank pulley to see exactly when it is firing and I suppose whether it is at all where it is expected to be. 

I gotta say, the vast number of errors I have made during all of this is .. vast. And it takes a while to find each one so I keep wondering what's going on here. Have I set TDC on the wrong stroke (not the compression stroke) so the dizzy is 180 degrees out? Are my HT leads in the right order both on the dizzy and into the engine. Is No 1 HT lead on the correct dizzy socket? (it's a side exit). Is the rotor pointed at the no 1 correctly? all I can think of for now.

I Do know we have spark at each plug for sure, having seen each one. A faulty spade connector to the coil meant no spark at all.

Of course I have checked all the above things, so many times I have lost count. BUT iterating procedures over and over again can lead to errors (like that faulty spade terminal).

Car has now started.

Hoo f…. Ray!

Well done.

Unlimited thanks to revilla for constant help and endless patience. 
The final trick was using the strobe timing light while cranking and using the camshaft sprocket timing marks instead of the crank pulley. 
 

oh and putting the HT leads on to the dizzy in correct order after the last recent removal.

I suppose at some point I should list the catalogue of errors and disasters

 so if I can’t be a good example, I can definitely be a terrible warning