What Causes Dizzy Cap To Get "furred" Up?

[pa402 0]

Hi guys

 

Just swapped my engine, replacing 1.9 with 1.9 and had no issues (done about 100 miles so far) until yesterday evening when it didnt start. As it was dark, didn't manage to check everything but after taking distributor cap off noticed that the four metal prong things had a white fur-like lining (like limescale in a kettle) where the rotor arm would hit them.

 

Basically I want to know whats causing this as my old engine never used to do this (its the same cap as only about a 1000 miles old) and whether this would be the cause for the non-start.

 

Any help appreciated before I investigate at the weekend.

 

Paul

[Ricardo 0]

Mix water with aluminum and steel (or other metal), and add some electrical currents, and you will get corrosion.

The furry ali is prob due to small amounts of water (vapour even) inside the dizzy cap. If enough it will break away and could short out causing week spark or hardened black deposits from being melted by a spark jumping accross to the pins from rotor. If this black stuff is Ali Oxide I don't think this isn't conductive.

[DamirGTI 344]

Well it's usual , however i dunno how to describe in which conditions this sediment starts forming on the cap terminals

 

Anyway it's some kind of “carbon deposits” , and surprisingly , it assists electrical conduction

 

Damir

[pa402 0]

Cheers

 

1 less thing to worry about. Hopefully I'll find why it doesn't start at the weekend!!

 

Paul

[DamirGTI 344]

Checked for spark and fuel delivery while cranking ?

 

Damir