Using Engine Restorer on older Briggs engine.

[sgkent]

yeah right. Had a CJ7 that loved to build up carbon. One night while the manifold was off I took some chunks of carbon and put them in every solvent I had.

MMO - no softening after 2 weeks
Acetone - no softening after 2 weeks
Water - no softening after 2 weeks
Carb cleaner well known brand - minor softening after 3 or 4 days
Alcohol Isopropyl - no softening after 2 weeks
Alcohol denatured - no softening after 2 weeks
Well known foam - no softening after 2 weeks
ATF - no softening after 2 weeks
Oven cleaner - softening over night but dissolves aluminum
Ammonia - softening over night but damages aluminum
GM upper cyl cleaner - over night dissolved into a toothpaste consistency

Maybe one of the new high mileage oils or Techron might knock some carbon on the rings loose. The GM stuff is retired I think although maybe available on Ebay for $$$. The easiest solution is pull the engine sump cover off, pull the head off, pull the connecting rod and piston out, extremely lightly hone the cylinder and put new rings on it. Put it back together.

 

[Auto Doc's]

yeah right. Had a CJ7 that loved to build up carbon. One night while the manifold was off I took some chunks of carbon and put them in every solvent I had.

MMO - no softening after 2 weeks
Acetone - no softening after 2 weeks
Water - no softening after 2 weeks
Carb cleaner well known brand - minor softening after 3 or 4 days
Alcohol Isopropyl - no softening after 2 weeks
Alcohol denatured - no softening after 2 weeks
Well known foam - no softening after 2 weeks
ATF - no softening after 2 weeks
Oven cleaner - softening over night but dissolves aluminum
Ammonia - softening over night but damages aluminum
GM upper cyl cleaner - over night dissolved into a toothpaste consistency

Maybe one of the new high mileage oils or Techron might knock some carbon on the rings loose. The GM stuff is retired I think although maybe available on Ebay for $$$. The easiest solution is pull the engine sump cover off, pull the head off, pull the connecting rod and piston out, extremely lightly hone the cylinder and put new rings on it. Put it back together.

Hello sgkent,

I've never tried a "cold" solvent experiment like that, but it sounds interesting.

Most solvents that used to actually work have been reformulated and hardly ever work. Chemtool cold carburetor/parts dip is one that I miss.