Alfa Romeo Forums banner
1 - 7 of 7 Posts

·
Certified Oldschooler
Joined
·
7,053 Posts
Discussion Starter · #1 · (Edited)
Your expert advice please:

1. What is the functional difference and intended application of 5mm versus 7mm green Cavis spark plug leads? What is appropriate for a '65 105 with standard ignition?

2. What is the functional difference between a so-called Bosch versus Marelli condenser. Several maintenance manuals say that the condenser is the same capacity as they make no differentiation (0.23-0.33 microfarad). Is it just the physical size (appear to be the same) or mounting?? And, is there any way to test a condenser (capacitor)?

Thanks, B
 

·
Premium Member
Joined
·
15,013 Posts
Set your multimeter to ohms and measure the resistance of the capacitor. It will probably be in the megohms range. Now reverse the leads and it should read negative ohms. This does not measure the capacitance or the breakdown voltage
but it tells you that the capacitor is functional.
 

·
Certified Oldschooler
Joined
·
7,053 Posts
Discussion Starter · #3 ·
I zero the Simpson 260 on the Rx10,000 ohm range and it reads negative offscale, like infinite ohms. When I turn the DC+/DC- switch (reverse polarity) if quickly jumps up and then goes down to negative offscale again. The 260 uses a 9V battery on this scale.

The ignition symptom I was having was massive across the board misfire, progressive over 15 minutes, not any one cylinder. Car jerking like a bronco. Replaced coil, plugs, rotor, cap, points, capacitor, cleaned (Bosch) dizzy trigger wire contacts and entrance insulator, gapped points, set timing static them max advance. OK now. I hit it with a fire hose (as all was of undeterminate age and I wanted to baseline it). Plug wires pending.
 

·
Registered
Joined
·
4,388 Posts
OK now. I hit it with a fire hose (as all was of undeterminate age and I wanted to baseline it). Plug wires pending.
[/QUOTE]

That's most likely your problem. When wires get old they'll develop cracks but still continue to work under most conditions. However, when they get wet they'll fail, often dramatically. Whenever you hose down an engine always spray everything with WD-40. It's a moisture dispersant and will usually cure wet-ign. problems. For a while. :)
 

·
Certified Oldschooler
Joined
·
7,053 Posts
Discussion Starter · #5 ·
You have a way of making me feel like I just wet myself on a cold day. Thanks Jim. I'll change them out for the green car's before we leave. The radiator overflow bottle was puking a bit as I over filled it after the coolant change. Coulda gotten on the wires. B
 

·
Certified Oldschooler
Joined
·
7,053 Posts
Discussion Starter · #7 ·
That's like the set I got but the clamp is yellow chromated. But, are they supposed to be 5 or 7mm on a 105. The label on the package for 5mm I got says, "Giulietta". The description just says "early".

I was also trying to figure out a way to attach them to the brown-red phenolic spark plug connectors but the black wires are internally attached to those connectors. Also, it would be helpful if the #4 wire had a right angle connector as it's right under the crossover air tube. B
 
1 - 7 of 7 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top