Unusual failure

[Casper]

Taking a nice drive on a rural Dorset road in the lovely Dorset sunshine, SWMBO/vehicle owner in the passenger seat, 'continental' touring kit sat neatly on the racking in the garage, the usual tools in the boot, mobile phone at home.  What a lovely day.  Nice steady 50 mph taking in the views the instantly, NOTHING.  Fortunately, a lay-by approaches and I pulled in there.

1.  Fuel pump is pumping (didn't expect that to be the problem due to the instantaneous failure).

2.  Flicked the points - nothing

3.  Spark test to earth - power to coil

4.  Spark test to earth - power on lead from coil to distributer connection

Dizzie is a 41449 (1500) type with a combined feed wire and capacitor.  Beginning to think the condensor might have failed to earth.

5.  Spark test to earth  on points spring - nothing

The feed wire had broken between the grommet where it enters the dizzie and the connector to the points spring.  It looked as if there had been localised hardening and the break was straight across.  No fraying, rubbing or stray strands.

Spare feed wire/capacitor in the 'continental' touring kit, and more in the 'Dizzie Parts' drawer, both some 5 miles away.  Fortunately there was sufficient slack in the cable run  for me to strip the wire and twist it together.  I was worried about shorting to earth but used the cable entry grommet to sleeve the twisted wire (one of the reasons the touring kit is on the shelf is that I have used the roll of insulating tape - and some other stuff- and not replaced it yet).  Sorted well enough to get home running perfectly.  Passed a Dolomite who would have passed us where we were broken down.  They use a 41449 and might have been carrying a spare!

SWMBO not too put out as she spent 10 minutes watching the views of Corfe Castle and a pair of circling buzzards.

Must sort out the touring kit (and also sharpen the side cutter on the everyday carry tool kit). 

Anyone else had this one?

C

 

[Clive]

Not on a dizzy, but on anoverdrive solenoid. On teh way to teh start of the RBRR in 2018, the OD started intermittently cutting out. I had a poke about, and wired in a direct power feed to teh switch, but no change.

Got near the start and stopped for a last meal, but had a look under the car and extra testing. Just happened to see a spark from the middle of the solenoid earth wire. The easiest solution was a fresh cable with new spade for teh solenoid end, and earthed to a new point. Removed my "power feed testing kit", scoffed fish and chips, all was well and still is.

Inspection of tegh wire showed it was very hard, I assume from oil and age. And had fractured. But I was so glad we found the issue, 2000 miles without OD would have been a pain.

[johny]

Sorry casper but I dont think its an unusual failure if its the original wire and now a gazillion years old! Isnt the dizzy backplate moved back and forward continually while driving by the vac unit, so apart from age, oil and heat the wire gets work hardened - reckon its done well to last this long🙂

[Pete Lewis]

agree heat hardens the plastic sleeving and movement works the wire to a fracture 

its the nature of parts well beyond their expected life  

any place thats got wiring in the hot and oily really need to be serviced out for some new , preferably silicon covered its stays flexible 

pete

[johny]

Yes Ive gone for an accuspark electronic unit which, for me, has been great and it comes with silicone insulated wires to run out of the distributor. They seem to be very flexible and oil/heat resistant but of course we'll have to see what theyre like in 40 years time🤞  

[Casper]

The part that failed is pretty new, certainly less than 5 years / 10,000 miles.  I couldn't imagine it regularly gets that hot.  Item GSC118 now tucked in pocket of every-day tool kit.

C.

[NonMember]

4 hours ago, Casper said:

The feed wire had broken between the grommet where it enters the dizzie and the connector to the points spring.

As johny says, not that unusual. I had exactly the same failure on my GT6 on the M40 quite some years back. (It now has a Lumenition.)

[johny]

19 minutes ago, Casper said:

The part that failed is pretty new, certainly less than 5 years / 10,000 miles.  I couldn't imagine it regularly gets that hot.  Item GSC118 now tucked in pocket of every-day tool kit.

C.

Thats interesting cos it brings up another possibility that unfortunately is well documented on here, the poor quality of replacement parts. It seems we now have to accept that just because a component has been replaced recently that doesnt mean it hasnt or wont fail pretty quickly☹️ 

[paul fosh]

same on my vitesse on a roundabout very embarrassing ,