Distributor (Lucas 43 D) clamp loss ANS: Yes and now extensive d.i.y. KNOCK SENSOR discussion (kit ordered)

[Gridgway]

I may have missed this, but what controls the advance? Is it just mechanical in the dizzy?  You've not got an ab14 Lucas module there as well?

[anthony1956]

5 minutes ago, Gridgway said:

I may have missed this, but what controls the advance? Is it just mechanical in the dizzy?  You've not got an ab14 Lucas module there as well?

We have mechanical advance only. Lucas 43 dizzy = no vacuum. No ab14 Lucas module (whatever that is - the original one?).

So this is about the timing changing overnight, without permisison.

[Gridgway]

So purely mechanical then.  Excellent. 

Another basic question.  How are you checking the timing?

[anthony1956]

2 minutes ago, Gridgway said:

Another basic question.  How are you checking the timing?

Stroboscopic timing gun on the cam sprockets - using 3 degrees for the crank's required 6 degrees.

The mechanical advance mechanism is shown above

Edited September 19 by anthony1956

[OldAndrewE]

4 minutes ago, anthony1956 said:

We have mechanical advance only. Lucas 43 dizzy = no vacuum. No ab14 Lucas module (whatever that is - the original one?).

So this is about the timing changing overnight, without permisison.

Although you have no vacuum advance you do have a vacuum advance base plate which it is why it needs to be fixed.  I have Lumenition in mine

[anthony1956]

One suggestion 

5 minutes ago, OldAndrewE said:

I have Lumenition in mine

the original, that's very good. Incidentally that dog bone is new, never had that in the previous electronic ignition; there is a plate screwed inside to the side and I have never touched it. I guess there is a bit that moves but I don't know which bit that is and anyway if it did my timing would be randomly all over the place which it isn't.

 

My current bet is it's happening during or after driving a hot engine, so my next test has to be to drive it and test the timing again at the end of play, not wait until next day.

Thought about gluing a camera down there, but I don' think it would survive. Markings on the base will have to do.

Edited September 19 by anthony1956

[OldAndrewE]

Yes, I think that should be the plan for now.  Get it right and mark everything up.  Hopefully you can then see what has moved if/when the timing changes

[anthony1956]

odds are it's the clamp as you suspected. So many other bits I have replaced basically due to metal fatigue so this is just another. The clamp does not loosen, so it has to be the body being able to turn regardless

Here's the.. an alternative solution list😉. 1 or 7 most likely 1, not enough miles at only 41,000 for the rest.

I need to find a paint brush more fine than the tippex one..

 

Edited September 19 by anthony1956

[anthony1956]

First nearly 5 hours of time lapse

https://www.dropbox.com/scl/fi/cwrgc29bqhbqh2ozn9gmf/DizzyClampTimelapse01.mov?rlkey=afn5f1aoylv57z0zhrk6ly9qq&dl=0

the flash in the middle is when I altered the spot light position

I've tippex marked it for the rest of the night.

I am not expecting any movement.

Edited September 19 by anthony1956

[anthony1956]

Okay so, no movement at all, and she starts if a bit roughly. Checked the timing and it’s the same as it was last night, and I marked the Distributor with Tippex, and there is no movement at all.

 

[Gridgway]

This must the ignition advance version of the Schrödinger's cat thought experiment where observation changes the outcome!

Rather bizarrely, the distributors on mine and Jen's FF2000s (pintos) had both massively moved overnight at Silverstone one race weekend between Friday test and saturday quali first thing.  Still a mystery.  They ran fine all day, then the timing was out overnight.  We can only think that someone moved them, but that's nonsense as who on earth would do that?

Sorry, not a very helpful comment from me.  Other than, once done up dizzys don't move, so the problem must be in the internals.  Or a problem of measurement.  If it was me, I'd swap another dizzy in (assuming I had one I could swap out or borrow or had a spare) to try and narrow it down.

[anthony1956]

Hi Graham, in the case of my 40-year-old Car, the received wisdom is that the clamp has lost its grip. There is a picture of it further above and it’s clearly very bent.

I have a new one on its way to me

Edited September 20 by anthony1956

[anthony1956]

and instructions:

#BDR   Replace dizzy clamp

I have asked Martin if there is advantage in doing all this with No 1 at TDC on the compression stroke.

Quote

 

Hi Anthony, 
Yes you  have to  remove it (lift the whole dizzy shaft out) completely .
However, there is a  foolproof  way.
 

Take a pic. to  show the  orientation of the  distributor .
Then remove the  cap &  take  a second pic. to show the  orientation of the  rotor  arm.
Undo the  clamp &  pull out the  distributor, as you  do this, the  rotor will  rotate  slightly.
Remove the  clamp.
Fit  new  one.
Orientate the  rotor  to its  post  removal position &  reinsert.
It will  then rotate & realign on  fitment to the  correct  posn .
What  could  possibly  go  wrong ? 🙂
Best Regards Martin

Distributor Doctor 01984 629540 Distributor Doctor Ltd
Unit 8 Old Brewery Road, Wiveliscombe, Taunton, Somerset, TA4 2PW
www.distributordoctor.com

 

 

Another version https://tinyurl.com/2edhkbes

Edited September 20 by anthony1956

[Gridgway]

It's pretty easy to do.  I would indeed set it to TDC and check that the rotor arm points to where #1 is on the cap.  Pull out the dizzy.  Watch the spindle move and get it back in in the right place.  If it nend up on the wrong place that is visually very easy to spot.

[anthony1956]

lovely, thanks - I imagine it will be easy the second time

Went for a run and the timing has not budged one jot. Granted it is way too far advanced, but no movement from this morning. I will wait for it to cool as it's very hot and check again.

wonder if i can find a youtube of someone lifting and refitting a dizzy: yes minute 5:00 of this: https://youtu.be/5a2X9mSSlQY?si=dCxnxR7NxIb-p5Z1

boy does he make aligning the rotor look easy

 

 

 

on a very positive note, the cooling system (an "overflow" system) continues to work as designed = perfectly) This was the original problem several months ago.

Edited September 20 by anthony1956

[anthony1956]

so I un-advanced it and now she won't start, or is very difficult. I have given up until tomorrow. 

in the over advanced state she was going like a rocket.. 

Edited September 20 by anthony1956

[anthony1956]

Heartily tired of all this so I have ordered a knock sensor system.

It's like being near the edge of a cliff without being able to see it, but knowing it's there somewhere. I want to know exactly where.

One of the odd factors is my main jets are 160 which is pretty large

Edited September 20 by anthony1956

[Gridgway]

What's one of those? And why?

[anthony1956]

You surprise me. It detects when the engine has "knocking" (also called "detonation"), what we used to call "pinking". This happens when the ignition is advanced too far and can lead to engine destruction. This fear is why everyone says "don't advance your ignition". My engine just feels like it really wants to so I'm going to give it the chance, but with careful and informed management.

Put it this way tuners use them to make race engines go faster.

Edited September 20 by anthony1956

[ScottR400D]

Will that work on your engine? How will it make any necessary adjustments? They are also used to retard ignition from ‘normal’ eg of poor fuel might be used. 
The point at which detonation happens can also vary with throttle opening and load so it’s not a perfect indicator of whether your timing is right. 

[anthony1956]

no indeed that's rather the point of it isn't it? 

It won't make any adjustments, I do that myself. yes sure, wot, load, fuel and altitude, but I am not planning to live near the edge, just to be informed 

so this thing doesn't tell us when timing is right, it tells us when it is wrong - which is the understandable great fear; so foot off, dial it back. Easy.

edit thanks for the reminder ("poor fuel"); My fuel additive bottle was faulty so that's now fixed. 

Edited September 20 by anthony1956

[ScottR400D]

Actually it doesn’t tell you anything about the timing. It just, if it’s in the right position  and actually senses detonation and not something else, tells you when you’re experiencing detonation. 

Detonation can be caused by various things. Plugs, mixture, fuel just for a few. 
 

Anyway, good luck. 

[anthony1956]

 

Come on, let's talk about how this can be a useful information addition device and how best it can be used? In a 40 year old non ecu no cat carburetted car?

"

"Anyway, good luck"

That's the very idea, luck is not required. 

Edited September 20 by anthony1956

[OldAndrewE]

What I am interested in is how you are going to fix it to the block.  All the knock sensors I have seen are firmly bolted to a special flat section of the block to give full block/sensor contact

[anthony1956]

me too!!