Author Topic: I've killed my spark and fuel supply - how on earth...?  (Read 4219 times)

Online Triton Thrasher

  • Scotland
  • Wise & Enlightened
  • *
  • Join Date: Feb 2009
  • Posts: 1927
  • Karma: 23
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #30 on: 31.07. 2016 18:45 »
If it won't even shock you, there's more wrong than a dirty slip ring.

Can you check whether the centre screw that holds the points plate on has electrical continuity to the casing?

Offline RichardL

  • Outside Chicago, IL
  • Wise & Enlightened
  • *
  • Join Date: Nov 2007
  • Posts: 6361
  • Karma: 55
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #31 on: 31.07. 2016 20:12 »
And I know what an HT shock feels like after an unfortunate incident with a James Captain when I was about 14. Quite a jolt.

Crispin,

You've only had ONE shock from HT? You must officially hold the forum record for the fewest such shocks.

I have a few ideas that I don't think have been shared yet, however, I'm not really optimistic any of them hold the answer if all you did between sparking and not sparking was clean the points.

In no particular order:

1. Is the correct notch in the cam ring sitting over the cam ring stop peg and is the stop peg visible and not broken? One of the pictures below shows two stop pegs and covers (though, there is only one in the mag). The other picture shows the stop peg location with the cover in place. If the stop peg is missing or broken off it is possible that the cam ring is rotated such that the points open when the brass on the slip ring is not in contact with the pickup brush.

2. It is possible that the connections of the plug wires within the brush holders have come loose or otherwise degraded. With so much trouble going on, it would not be a bad idea to renew these connections anyway, meaning, cut back a little wire for a fresh end for the pickup to screw into. (we assume you are using copper plug wire and not carbon-impregnated fabric filament plug wire).

3. Be sure the springs that hold the brushes in the holders are seated at the bottom of the holes in the holders. They may be pushed down with a very small screwdriver (I have also used a cut-off toothpick). 

I think the idea of finding a bit of local help is a good one. It doesn't mean you couldn't do it yourself. Sometimes when we are frustrated we just go blind to the big picture and it can really help to have another set of eyes on the issue.

Richard L.


Offline duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4528
  • Karma: 41
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #32 on: 31.07. 2016 22:32 »
 
Quote
Another possibility: How critical is the tightening of the bezelled ring that holds the black Bakelite end cap in? There is a little brass triangular marker which sits in one of the grooves, but no indication of which one it should sit in. I took it off and put it back fine the first time, but could this be an issue? I have it finger tight at present.

 I think the 'pointer' may be an anti-rattle doodad, and you need to screw the cover on so it's snug...?

 Without re-reading the whole thread, is it possible you've crossed the plug leads? Swap them over again anyway.. *conf*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline RichardL

  • Outside Chicago, IL
  • Wise & Enlightened
  • *
  • Join Date: Nov 2007
  • Posts: 6361
  • Karma: 55
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #33 on: 31.07. 2016 23:26 »
Dutch,

Apparently, Crispin is geting no spark when testing by placing hand on engine and touching tongue to lead end, so, issue of crossed leads might be there, but not the basic problem, me thinks.

Richard L.

Offline duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4528
  • Karma: 41
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #34 on: 01.08. 2016 00:55 »
 You;
Quote
Apparently, Crispin is geting no spark when testing by placing hand on engine and touching tongue to lead end, so, issue of crossed leads might be there, but not the basic problem, me thinks.

 Me; brainfart *shh*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline CrispinA10

  • A's Good Friend
  • ***
  • Join Date: Mar 2015
  • Posts: 63
  • Karma: 0
  • 1960 Super Rocket in RGS spec. 1965 Enfield GT
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #35 on: 01.08. 2016 19:00 »
Many thanks for all this - I am working through ideas one by one.
However the suggestion about asking someone who knows a lot more about mags than I do and who lives nearby is a good one.
Have just phoned a bloke named John who lives in the next village. You can tell he's a great bloke because he keeps a pair of Triumph GP racers in his sitting room and has had loads of BSAs including a Goldie. He went through most of the ideas posted here, and after gathering that I was reluctant to take off the mag and take it apart for detailed study, he said: "and if nothing else works and you're not in a hurry, I might be able to take a look at it."
I'm to clean off that slip ring with petrol, check the length of the carbon brushes and if nothing happens, phone him back...

Offline CrispinA10

  • A's Good Friend
  • ***
  • Join Date: Mar 2015
  • Posts: 63
  • Karma: 0
  • 1960 Super Rocket in RGS spec. 1965 Enfield GT
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #36 on: 04.08. 2016 16:46 »
Right - progress I think! Perhaps my magneto isn't dead after all. Have just discovered that if I kick the bike over with the points end cap removed completely, then there is a faint spark at both plugs. Pale and weak, but a definite spark. Put the end cap back on (with or without the kill lead) and nothing.
What could cause that? The carbon brush in the cap looks clean and springs in and out as it should. There is no visible damage and it looks in excellent condition.
I'm assuming that the mag should generate a big fat spark rather than a Tinker-bell style flicker - might that mean the condenser did give up the ghost at exactly the moment I cleaned the points?
Really looking forward to some suggestions - day off work tomorrow so I can fiddle at will.

Offline CrispinA10

  • A's Good Friend
  • ***
  • Join Date: Mar 2015
  • Posts: 63
  • Karma: 0
  • 1960 Super Rocket in RGS spec. 1965 Enfield GT
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #37 on: 04.08. 2016 16:59 »
This is the type of cap I have - not sure if there are varients.

Offline metalflake11

  • Resident Legend
  • *****
  • Join Date: Aug 2012
  • Posts: 678
  • Karma: 9
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #38 on: 04.08. 2016 17:23 »
Firstly, the brass pointer thing is there to sit in the serrations in the end cap to stop it unscrewing, period. With the cap off the end of the mag, take the plug caps off the H.T. leads and hold the ends close to the engine and kick it over........... No plug, no cap, just the end of the lead close to the engine. Let me know if the spark improves. I'm on line for a bit and will reply quickly.
England N.W
1960 A10
England

Online Triton Thrasher

  • Scotland
  • Wise & Enlightened
  • *
  • Join Date: Feb 2009
  • Posts: 1927
  • Karma: 23
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #39 on: 04.08. 2016 17:50 »
Ok, it sparks with the points cover off.

Does it spark with the cover screwed on, but no kill switch wire attached to the cover?


Offline metalflake11

  • Resident Legend
  • *****
  • Join Date: Aug 2012
  • Posts: 678
  • Karma: 9
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #40 on: 04.08. 2016 17:54 »
Ok, it sparks with the points cover off.

Does it spark with the cover screwed on, but no kill switch wire attached to the cover?

No.
England N.W
1960 A10
England

Offline CrispinA10

  • A's Good Friend
  • ***
  • Join Date: Mar 2015
  • Posts: 63
  • Karma: 0
  • 1960 Super Rocket in RGS spec. 1965 Enfield GT
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #41 on: 04.08. 2016 18:42 »
The spark is no better using the bare end of the HT lead with no cap.
No, it doesn't spark with the cap on whether the kill wire is attached or not. Unless..... of course there is an intermittent fault and there is an element of coincidence.

Offline RichardL

  • Outside Chicago, IL
  • Wise & Enlightened
  • *
  • Join Date: Nov 2007
  • Posts: 6361
  • Karma: 55
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #42 on: 04.08. 2016 19:14 »
Take a look at the attached image. It appears you are missing an insulating cork washer between the steel washer and the end-cap body. I believe that would explain it.

Richard L.

Online Triton Thrasher

  • Scotland
  • Wise & Enlightened
  • *
  • Join Date: Feb 2009
  • Posts: 1927
  • Karma: 23
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #43 on: 04.08. 2016 19:30 »
Take a look at the attached image. It appears you are missing an insulating cork washer between the steel washer and the end-cap body. I believe that would explain it.

Richard L.

The brush holder certainly does have to be insulated from the magneto casing.

Offline CrispinA10

  • A's Good Friend
  • ***
  • Join Date: Mar 2015
  • Posts: 63
  • Karma: 0
  • 1960 Super Rocket in RGS spec. 1965 Enfield GT
Re: I've killed my spark and fuel supply - how on earth...?
« Reply #44 on: 04.08. 2016 20:04 »
My response appears to have disappeared into the ether rather like my washer - basically it said Arggggh! Then well spotted mate to Richard L - then thanks to everyone else who has been so, so helpful. Off to grovel around on the bricks in attempt to find the washer...