Misfire ?

[morgan]

Dave - Thanks as always. Yes, the middle of cap springy and no fore/aft in-the-shaft.
Adam - Switched off light. No display.

Todays update quarantined sportsfans.
So the new cap and rotor arrive. I figure for the price of a tank of petrol it eliminates something.

Checked them all carefully - the MSD cap actually comes with a little cardboard tang to check the height of the spring in the middle is within range.

Swapped em over, fired her up.
I didnt roadtest BUT she didnt pop or bang once. The idle is dreadful anyway (v rough cam) but she ran, after a minute or so I was able to remove foot from throttle and she sat lumping away - no bangs, no pops. Ran her out of garage and back and she didnt stall or cough. So early indications are good - fingers crossed pending road test.

Question is still why. Cant see anything obviously wrong - the old cap and rotor have done MAYBE 5K ? Few years old now but still. No cracks, clean enough, spring gap good. If this DOES cure it I'm a little stumped. But I'll report back to my fave therapy group.

Morgan.

[Pete]

The springs look a trifle heavy in the photo.

Also, if you get really keen, you can phase the rotor too....

[morgan]

Interesting point. The new spring did sit lower, i noticed on removal. I’ll check it in the cardboard tang thing.

I dont think i want to go phasing ... haha - i’ll settle for ‘working’. When it comes to see you, knock yourself out.

[Pete]

...you are not yet the master, young Skywalker; but the force is strong.....

[morgan]

Duh - just re-read post. Springs are stock curve. I had a faster advance setup ( lighter springs) but reverted to stock when troubleshooting.
So its 16/34 all in at 3k with stock mech advance currently. (Verified to be true)

I thought you meant the rotor ‘spring’ - because that came with a gap adjuster which was a new one on me - i thought a rotor was a rotor - apparently its sensitive.

[Dave999]

that ball bearing in the cap should be springy and the bendy tang on the rotor should and obviously is, springy

wonder if you had a dirty greasy not springy enough ball.....sounds nasty



dave

[morgan]

Will inspect my dirty ball and give it a prod. Will report back on its suppleness/springyness.

[Pete]

I have had those MSD Pickups go down too....

I drove down to the fire up lane, got all the way to the front and was called othe line and the motor would not run, period.

I changed it for a spare MSD Distributor (as you do) and the car fired up straight away....

[morgan]

Well, had a look. Pickup in cap gave a definite ‘pop’ but now moves freely. This might have been it - i could prove by swapping back i suppose... we’ll see how bored i get :-)
Started her agin, all the way up to temp. Sweet as. So i think its cured - one for the knowledge banks anyway...

Thanks as always chaps.

[RobTwin]

Well, had a look. Pickup in cap gave a definite ‘pop’ but now moves freely. This might have been it - i could prove by swapping back i suppose... we’ll see how bored i get :-)
Started her agin, all the way up to temp. Sweet as. So i think its cured - one for the knowledge banks anyway...

Thanks as always chaps.

Nice one

[Dave999]

YaY!!!!

[morgan]

YaY!!!!

Plus she has better plugs now Dave. Its all learning !