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Testing Engine electricals?
Andy - January 10th, 2004 at 10:00 AM

So how do you all fault find electricals on your engine??
Thought this might be useful to track down problems with poor or no spark.
How do you all check the following:
Spark plugs
plug leads (copper or silicon)
coils
condensor
rotor
distributor cap
points (or electronic)
power lead
:thumb

Andy - January 10th, 2004 at 10:09 AM

I'll start with my simplified answers.
Plugs: visual check only for any build up that may cause misfiring. Check also gap, cracks in insulator, clean thread and good sealing washer.
Leads (copper) check they are clean (cable outer), no corrosion on lead ends and resistance (value varies depending on type) For silicon ones, no idea?
Coil: measure primary resistance (again varies coil to coil). Anything else?
Condensor: No idea?
Rotor: Visual check it's clean and not cracked. Measure resistance (varies rotor to rotor)
Cap: Visual check it's clean and not cracked.
Points: Visual check they are clean and not burnt and gapped correctly.
Power: Check 12V makes it to coil. (6V for 6V systems!!)
Anything I missed?
Hope this helps people :)

count - January 10th, 2004 at 02:50 PM

Thanks Andy,

I must admit:cry
I've not done any serious,
or even NOT so serious work on the Dub.

Because of where I live I am going to have to:(

I'm copying your write up to Word for my refering back to when needed.

The Guzzi [you know? 'older' pushrod Air-cooled Italian Motorcycle] Forum
has quite a few pages of similar.
It's at:-
http://home.pacific.net.au/~cusacks4/aigor/ 
More specificly:-
http://www.mypage.tsn.cc/rdd/TT/ 

Would someone please comment on these?
Some 'outside' feedback.

Ivan in Oz
count@[remove]norcom.net.au

vw54 - January 10th, 2004 at 05:22 PM

Thanks Andy

I was going to say that most checks would be Visual but you have described them 2 a Tee

11CAB - January 10th, 2004 at 08:35 PM

Copper leads should have close to zero resistance....

Rotor Button should have about 5000 ohms resistance (less is better than more)

Silicon leads should have 5000-8000 ohms per 30cm of lead.

Coil you are looking at about 3 ohm resistance

Plugs check for gap, also for the shape of the electrode (should be nice and square)

Cap, check for cracks and carbon tracking, also make sure the centre carbon and spring are intact

Andy - January 10th, 2004 at 09:28 PM

Cool,
Thanks for all the info 11CAB.

Anyone else have anything to add?

Might do one on fuel next :thumb

MickH - January 10th, 2004 at 09:35 PM

hehe...fuel....throw in match.If burns is good.:jesus. Sorry have hit da RUMMM(hic)

Andy - January 12th, 2004 at 08:30 AM

Oh,
just to add a condensor should read ~0.2uF.