In case anyone is wondering how I know the capacitors are leaking and that it is not flux residue.....when removing these capacitors some were so corroded on the leads that they virtually fell off the board and there was a collection of corroded metal where the leads had one been. A quick sniff test also confirmed leaking electrolyte. Once the capacitor is removed, the remnant leads left on the PCB can be seen and the corrosion on their surface is very obvious. They are a very dark grey colour and easily peel off of the solder pad as corrosion eats away the solder joint interface. You can often see the lead corrosion is visible where it just pokes out past the insulator plate that sits between the capacitor case and PCB. Sometimes there is wet electrolyte under the capacitor, other times the electrolyte has dried to a yellow dusty material. Wet or dry, the electrolyte really pongs when heated with a soldering iron.
I should have taken a photo of the corrosion evidence. Apologies, I was too keen to clean everything ready for the new capacitors to be fitted. If I find another corroded set of leads I shall take a picture.
If in doubt, replace. It saves problems further down the line and may even improve an instruments performance if the capacitor has fallen out of specification due to age.
Fraser
Home
Help
Search
Login
Register
