Mechanics
Tip
Mechanic's Tip: When it comes time to wash greasy parts one of the best strategies I know of is to locate a discarded gallon-sized plastic mayonnaise jar [usually available from a local restaurant for the asking]. Fill the jar about half full with Stoddard's solvent or kerosene. Put any small parts you need to clean in the solution and close the lid tightly. It is best to remove heavy grease and greasy buildup first. Then shake the contents vigorously [more vigorously for steel parts, but less for "soft" parts such as carburetter bits, brass or plastic items, etc.]. It is best not to mix delicate parts such as carbutetter floats with heavier items as they will be damaged. It should also be stressed that the hands must be placed at the top and bottom of the jug at all times while agitating the contents because the solvent [and parts] could fly out should the lid come off inadvertently! Safety glasses should be worn at all times as well. Next, pour off the liquid solvent immediately after shaking the jar, so as to empty both the solvent and the dirty particulate component held in suspension in the cleaning fluid. At this point it is best to leave the dirty solvent mixture in a second container to settle out for 24 hours, whereupon the debris will mostly be found at the bottom of the container. Once the material has had enough time to settle out pour the better, cleaner part of the solution off the top, being careful to leave the debris and the last 5 percent of the dirtiest portion of the mixture at the bottom. It is often best at this point to remove the parts by hand and then clean out the gunk at the bottom of the jar with a rag or newspaper.
If speed is the order of the day, then fresh solvent could be reintroduced to the jug while waiting for the first charge of cleaning fluid to gravity-clean. The remaining debris can then be mixed with sawdust and sent to the landfill, but never placed haphazardly where it could contaminate groundwater or runoff. It should be stressed that while other solvents such as petrol or lacquer thinner would clean parts more aggressively and thoroughly, the flammability and very low flash-point of such materials make them far too dangerous to be considered safe to use.
It may also prove advantageous to remove the parts being cleaned from the jar periodically to wash them off with water, and to reintroduce them to the jug with a fresh change of solvent. For really clean parts it may prove beneficial to introduce an industrial-strength cleaner such as "Mr. Clean" to the jug in a fairly high concentration once the solvent cleaning is completed. This strategy renders the parts virtually clean enough for painting, when rinsed in fresh water. In the interest of economy and ecology, these cleaning materials should be saved and reused over and over, perhaps strengthened with a fresh charge of virgin product.
It should be noted that is not a good idea to clean both "hard" and "soft" materials at the same time, for example steel and white metal or brass parts, or heavy and delicate parts, as the heavy parts could easily damage the smaller bits. Also remember that many British seals and gaiters are made of natural rubber and that when exposed to solvent for more than a very brief period of time will cause them to swell up. Solvent may be used on these parts to remove heavy grease but the rubber parts must be rinsed off thoroughly within minutes or they will be damaged. Rather obviously hydraulic brake seals and common shaft seals should never be reused. Such practices inevitably yield dire results.