Control of Low-Temperature Sludge In Passenger-Car Engines

THIS paper evaluates a new class of detergents, specially effective in controlling sludge formation at the low or moderate temperatures most often encountered in passenger-car operation.

This new Detergent C (a copolymer of lauryl methacrylate plus diethylaminoethyl methacry-late) has undergone extensive bench and laboratory tests in comparison with three other major classes of detergent. It exhibits, among other attributes:

1. 1.
   Complete solubilization of sludge.
2. 2.
   Complete carbon suspension under both wet and dry conditions.
3. 3.
   Residual detergency, as indicated by dispersancy in blotter tests under wet and dry conditions.
4. 4.
   Ability to prevent agglomeration and precipitation of sludge formed during oxidation of lubricating oils, with and without presence of water.
5. 5.
   Effective sludge suspension after 40-hr laboratory tests, and after several months of storage.