Picture of How To Clean An Intercooler

Looking inside the intercooler of my '06 MINI Cooper S when I had it off recently, to replace the supercharger, I noticed that the inside was coated in a thin film of oil. This decreases the efficiency of the intercooler by fouling up the heat transfer between the intercooler fins and the air flowing through it.This is the solution I came up with.

Disclaimer: I don't know how your intercooling system works. This How To won't do damage to a first generation MINI Cooper if followed properly but there could be a slight difference in your system that could cause problems. It's unlikely but possible so read the Instructable and then make a decision based on your situation. It is also possible that the inside of your intercooler may never need cleaned. In Gen 1 MINI's the crankcase vents into the air system, which means oil vapor and mist gets into the air system, making a mess of things.

Step 1: Materials and Tools

Picture of Materials and Tools
  • Acetone, 1 qt,  $7 - Acetone evaporates quickly and is safe for the materials we will be using it on.
  • Rubber Bands,  x 2, Free - Look at the size of the openings on your intercooler and choose your bands accordingly. Heavy duty bands are best.
  • Plastic Bags, x 2, Free - Try to find two without holes.

  • Gloves - Make sure solvent won't dissolve them or soak through.
  • Mask - Brain cells are good, acetone hates brain cells.
  • Bucket - I used an oil pan already half full of junk coolent. Check all applicable local laws for disposal of used solvents.