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131mirafiori home => The Garage => Topic started by: Crazypierre on January 26, 2020, 09:10:10 PM



Title: Non starter- HELP!
Post by: Crazypierre on January 26, 2020, 09:10:10 PM
Hey Guys,
You've always helped me with my 131 issues but hoping you can assist with something else.
I've acquired a 1970 Fiat 500 with a 652cc Fiat 126 engine in it.
It had an erratic idle but always started very easily.
Then one day, doing about 50mph, it started to splutter and run rough, losing revs, ran a bit more, then finally cut out.
Had no tools so called the AA man who diagnosed fuel starvation or blocked carb.
He stripped the carb, cleaned all the jets, tested fuel pump, all good but still wouldn't start so towed me home.
Next day, I removed carb again, cleaned all the jets through, tested the needle valve, all good.
But...no start.
Plugs wet so fuel getting through and there's a spark.
Changed the plugs, they spark but still not starting.  It doesn't even attempt to fire.
So, thinking ignition issues: it has a funny electronic ignition set-up whereby the normal coil has been replaced by this black electronic ignition coil/module, the rotor in the distributor removed but the contact points and condensor are still in/on the distributor....but the HT leads don't run from the distributor (See pics)  I think the electronic ignition still relies on the points as the switch/trigger for the electronic ignition coil/module.
Any ideas what could be the cause of the engine dying and now non starting?
I'm thinking could this be a condensor failure which is causing irregular sparking at the wrong time? (Because there are sparks at the plugs....) Maybe the erratic idling was the condensor starting to break down till it failed completely?
Thoughts from the experts?
Thanks
Pete



Title: Re: Non starter- HELP!
Post by: Henk on January 29, 2020, 05:41:02 PM
Never saw this set up so far....
But I think you are right, the coil module uses the breaker signal, I think
if you have a spark but it is not starting, it normally means be that the timing of the breaker points is not ok. (Or cam belt/chain, whatever it has)
Is the distributor still fixed or maybe got loose and turned a bit so timing is too far off...?
Did you check the setting / timing of the breaker? (old school with testing bulb)


Title: Re: Non starter- HELP!
Post by: Crazypierre on January 29, 2020, 05:48:23 PM
Hi,
Thanks for your thoughts.
The distributor has not moved, the clamp holding it to the block is still solid.  I cleaned the points and the gap is good.
I've since found out this is a "wasted" spark set up meaning the coil fires the two spark plugs at the same time with one firing on the compression stroke (as it should) and other on one of the other strokes where the spark is not normally needed and has no use- hence "wasted".

Do you think the condensor may be duff making a weak spark?

Regards,
PC


Title: Re: Non starter- HELP!
Post by: Henk on January 29, 2020, 07:40:45 PM
yep, bad condensers can cause a weak spark.
they are not that expensive so worth a try.

You cleaned the breaker contacts but also check the path to ground