Weird Ignition fault

[Richard B]

Stephanie's 1300 Dolomite broke down last week and was recovered home.

On investigation the timing was 180 degrees out. So swapped HT leads 1 & 4 and 2 & 3 and the 1300 ran straight away. Put this down to the recovery mechanic trying to fix it and getting it wrong. Still strange that No.1 was by the block because I thought I had set it up correctly (previously) with No.1 away from the block.

This week she broke down again, guess what. Yep ignition 180 degrees out! Swapped the leads and the engine ran fine again.


So what is causing this? Dissy jumping or a securing pin sheared in the dissy or drive gear?

[beefertoo]

i'd go for the pin in the drive gear,, doesnt the offset dog mean it will only go in one way?

[Nick Jones]

Pin sheared in the drive dog at the bottom of the dizzy.  Don't think there is anything else it could be  :-/

Nick

[mikeyb]

236 wrote:

i'd go for the pin in the drive gear,, doesnt the offset dog mean it will only go in one way?

It is possible to refit the dizzy & drive dog with the offset 180 deg out and still have the car run - ask me (or rather Mr Scrapman) how I know!

We drove his GT6 based Moss Monaco to Lemans and all the way back to the port at Dieppe before it jumped around 180 deg into it's proper position, causing us much grief in trying to work out why the car would not go!

However if it's done it twice, then I too would suspect the pin!

[Nick Jones]

I would be very wary of the distributor generally as you have to wonder how the drive pin got broken?  Not a very high-torque device a distributor...... shouldn't snap a roll pin!

Nick

[junkuser]

Is the dog fitting all the way down into the slot in the drive?

[piman]

Hello richard,

the puzzling thing is the failure going exactly 180 degrees out, which I don't think will happen with a broken pin etc? No answer, I'm afraid, as I'm not so familiar with that engine.

Alec

[heraldcoupe]

junkuser wrote:

Is the dog fitting all the way down into the slot in the drive?

That's my thought too. If the distributor is 'just' engaging in the slot, there's potential for it to jump.
Check the drive gear is fully engaged and can't drop further as the distributor is introduced, and that there isn't endfloat in the distributor itself. Beyond that, ensure that the distributor drive engages cleanly in the slot and that there's no burring.

I can't see what else can cause this precise 180 degree shift,

Cheers,
Bill.

[Richard B]

heraldcoupe wrote:

If the distributor is 'just' engaging in the slot, there's potential for it to jump.

and that there isn't endfloat in the distributor itself. I can't see what else can cause this precise 180 degree shift,

Cheers guys, echoes my thoughts.

I've whipped the dissy out and there is significant endfloat in the shaft; looks like wear in the bronze thrust washer. Pin looks ok.

Also the shaft had dislocated again after we got the engine running on Sunday. At a guess it happened when the engin was turned off. The rotor arm was pointing to No.3 instead of No.1. when I rotated the shaft back to No.1 it clicked into place and would not move. Obviously with the car/engine running its able to come unstuck.

I've ordered a recon Distributor from TD Fitchetts, so hopefully that will resolve the issue.

[Richard B]

Just fitted the recon distributor.

Another part of the problem was that the clamp was very high on the slot. I think it was a combination of this and the endfloat in the main shaft.