Tech Tip: Got Rust?

Here is a little information that may help some rebuilders combat internal flash rusting that can occur from converters that sit on the shelf for more than a few days. Most rebuilders clean and rebuild converters without a thought of what happens to the internal converter parts after the cap is put on the hub and the box is closed. For some rebuilders this is not a problem. For others it can be an expensive oversight. After completion of the wash cycle, the internal components are subjected to a rinse and dry, most parts will be machined as required and travel to a storage or a staging area to be used within a few days or even a few hours. The rust process has started. Rust particles start forming immediately when exposed to oxygen. Oxidation on the surface, too small to see without the aid of a high power microscope, begins to form without being observed. The torque converter is assembled, packaged and put into inventory awaiting a future delivery. A few days in storage before installation presents little or no threat, but a few weeks can create a disaster.

What problems may occur? Premature bearing failure, reduced performance and increased wear rate, of the clutch material, noises from pitted bearing and thrust surfaces and cross contamination to the transmission are common issues.

This leads to a conclusion that a rust prevention program must be initiated. It must be a product designed to be added to the internal parts after completion. It must coat the parts with an oxidation barrier, be compatible with transmission fluid without the performance being compromised, environmentally safe and affordable. Transmission fluid alone is not enough. Most ATF contains less than 10 parts per million of any antioxidant and will not prevent rust. You must use a product designed for ATF like Flashguard. You simply add 1 ounce into 1 gallon of ATF and add into the converter. It is available from The Spartacus Group at 815-637-1574.

Dennis Sneath
Midwest Converters, Inc., Rockford, IL

– FoundĀ in August 2010 Newsletter