The Nitty Gritty On Small Parts Cleaning: Many Ways To Clean Small Engine Parts

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Ehman said these micro-bubbles rapidly form and then violently collapse or implode when they come in contact with the surface to be cleaned. "It is estimated that pressures as high as 10,000 psi are produced in the immediate area of each implosion," Ehman said. "These countless implosions produce a universally dispersed and highly effective scrubbing on all exposed and hidden surfaces of the parts removing carbon, varnish, rust, grit and grime from every surface, nook and cranny."

It's easy to understand why cleaning equipment manufacturers are looking at ways to improve their machines. Nichols, an ASE Master Machinist, said cleaning was the most expensive, time consuming and critical step in engine rebuilding in 1964, when his shop opened for business, and it is still true today. "How parts are cleaned and inspected determines whether or not a machine shop will make a profit or go under," Nichols said. "Yet many shops pay the least wages to and give little or no training to employees who do the dirty work of cleaning.

In our shop cleaning employees must complete a training course on proper cleaning and inspection methods. Then, depending on their score, they receive a pay raise and are put in charge of scheduling all work going through the shop...making sure each machinist receives the correct, clean parts for each item at the proper time."

But Nichols added that while cleaning small parts can save a shop money by not having to purchase new replacement components, cleaning comes at a cost. "Many times we must clean items at no charge just to ensure that it won't compromise the other machine work we do," he said. "For example, it may take 30 minutes to properly clean a timing cover on a chain-driven DOHC Nissan - a value of $35. But getting a customer to pay for that is almost impossible. Most customers, even professional mechanics, don't value cleaning very highly. But not cleaning the cover may jeopardize the $2,000 long block we just rebuilt."

Doug Anderson, vice president of Grooms Engines, Parts, Machining, Inc., Nashville, TN, said rebuilders are constantly looking for ways to reduce the costs associated with cleaning small parts. "For years we had a solvent sink in the assembly area for detailing small parts, but it became too expensive to operate, so we tried something different."

Anderson said because the unit was inside the shop, Grooms also had to retain a VOC permit because of the evaporation of "volatile organic compounds" from the solvent. "In order to maintain the permit, we had to measure the amount of solvent that came and went so we could determine how much had evaporated," he said.

Anderson said the shop also was required to keep the lid closed when the sink wasn't in use, as well as keep a log of the hours that it was used. Once a year, a report had to be submitted and a permit fee paid to the city. A few years ago, Grooms purchased a sink from Grainger, Chicago, IL, a nationwide supplier of industrial and shop tools and equipment, and connected it to a 35-gallon drum that has an electric immersion heater installed in it. Using a water-based cleaner at about 12% solution heated to 130° F, the sink is located near one of the shop's jet spray washers. The location makes it easy to pump the solution into the holding tank when it needs to be changed. "By eliminating the solvent, we have been saving more than $8,000 a year, " Anderson said. "And we were finally able to eliminate the need for a VOC permit."

Rebuilders also need to keep in mind that when it comes to cleaning aluminum parts, the cleaning processes are often very different than those associated with cleaning steel/cast iron parts. Kansas Instruments' Dave Cox said although aluminum parts will have many of the same carbon deposits and oil sludge on them as their cast iron counterparts, special care must be used to clean them. "Small aluminum parts cannot be baked at high temperatures nor cleaned with harsh chemicals," Cox warned.

Automotive Machine & Supply's Nichols said his shop has specialized in aluminum and magnesium engines and small parts for 34 years. "We have experimented with many different processes trying to find the best for quality, the environment and profits," Nichols said. "We think we have found the best for our shop - but we are continually looking for better ways to clean parts. We've even tried blasting with baking soda and dry ice," he added.

Another change in small parts cleaning is the types of solvents available. Because of environmental concerns, Nichols said "old-fashioned carburetor cleaner" is no longer used in the cleaning process. "The old soaking kind of carburetor cleaner is too harmful for the environment," said Nichols. "We use non-chlorinated, consumer-grade spray cans. This is cheaper than other products and satisfies the hazardous waste and workplace laws.

Today, more and more parts cleaner manufacturers are creating water-based or bio-degradable cleaners and degreasers that meet Occupational Safety and Health Administration (OSHA) and Environmental Protection Agency (EPA) standards.

One such aqueous, non-volatile parts cleaner/degreaser manufacturer is Mirachem Corp., Tempe, AZ, which makes a spray can parts cleaner. Founded by Jim Edwards, a former auto racer who sought a solution to solvent sensitivity as he restored cars, Mirachem addresses today's environmental issues which weren't major concerns for parts cleaning products in the past. "When I first formulated this non-caustic, non-corrosive product 20 years ago, no one cared about the environment," Edwards explained. "I was just looking for a way to stop the skin from falling off my own hands.

"Now no company that operates in a global business climate can afford to ignore air quality issues. Workers demand safe solvents, so it helps that these products also work as well as the previous hazardous solvents."

Andy Hernandez, who manufacturers the Green World environmental parts washer, said today's biodegradable soaps, along with heated water, can clean just as effectively as caustic solutions. Hernandez said although separate soaps are available to clean only aluminum or only steel/cast iron, many shops blend the soaps to save cleaning time. "Biodegradable soaps are blended to clean aluminum, cast iron, steel, plastic and rubber without damage," he said, adding the soaps also contain an anti-rust additive to protect parts from corrosion.

Following other cleaning processes, sometimes parts are given a coating to protect them against rust while in storage. Kansas Instruments' Cox said parts that will be in long term storage will look better with some type of coating protection, adding, however, that many rust inhibitors used in rinse cycles of today's cleaning equipment do eliminate the need for a protectant.

Nichols said after most small parts are aqueously cleaned at Automotive Machine & Supply, they are dried in a bake oven followed by a shot of WD40®.

Just as some small engine components are treated following the cleaning process, J & H Diesel Service's Harper said his shop will cold blue the nozzles of some fuel injector models to prohibit rusting while in the engine. "Some injectors are also painted before they are returned to the customer," he said.

The issues of sorting and storing small parts can also be an obstacle for remanufacturers. Dana Pickup, president of Cuba Specialty Mfg., Inc., Fillmore, NY, a manufacturer of automotive parts baskets, said there is growing interest by rebuilders for an inexpensive and organized method to sort, clean and store their small parts for cleaning. "There's a lot of rebuilders out there using various sized paint cans or coffee cans that are drilled with holes in order to clean and store parts," Pickup said. "But there really isn't much in the way of an inexpensive, convenient parts basket system available to the industry."

To accommodate that need, Pickup said Cuba has added two sizes of Small Parts Keepers to its popular Gee-Z line of parts baskets. "These Parts Keepers are specially designed to hold and organize the small parts associated with carburetor, engine, electrical and transmission rebuilding," Pickup said.

Pickup explained his Gee-Z line of parts baskets were introduced at the Engine Rebuilders Association (AERA) show in April of 1997. When talking to rebuilders, Pickup learned many shops were searching for a smaller version of his economical baskets that could hold small engine parts. Pickup then designed a smaller-mesh basket, calling it a Small Parts Keeper. "We took prototypes to the Automotive Parts Rebuilders Association Show (APRA) in October or '97 and were met with tremendous response," Pickup explained. "We sold thousands of the baskets at the show, mostly to electrical rebuilders. When we returned from the show, we went right into production."

Cuba said the Parts Keepers are made of size 8 mesh (1/8"-holes) galvanized wire and can be used in aqueous spray washers, spray booths or tanks to soak small parts. Pickup recommends using the baskets in non-caustic solutions. "We are experimenting with a stainless steel wire design because the galvanized coating will wear off in a caustic solution," explained Pickup. "The stainless steel wire will be more expensive, but we're continually looking at ways to accommodate the rebuilder's cleaning needs."

The following are some component parts cleaning tips provided by rebuilders and parts equipment manufacturers interviewed for this article. Other forms of cleaning may be just as viable depending on the quantity, materials and equipment employed.

Pistons - Disassemble and remove rings. The piston may be initially cleaned in an aluminum-safe spray washer or soak tank. The second process will be to glass bead the piston top only.

Piston cleaning is usually not done as labor costs are usually too high and potential part failure rates too high. Blocks usually have wear areas and require reboring anyway. Nichols said pistons are usually replaced new in his engines, although those that are reused are soaked in a hot detergent vat, rinsed with water and the tops carefully and gently wire wheel buffed.

Intake valves - soaked in hot caustic and wire wheel buffed; stems are polished with a 600-grit belt and inspected for burrs, etc. Valves also can be cleaned in a media tumbler with a solvent where stem protectors are used on the valve ends. Valves can then be glass beaded for cosmetics.

Non-hydraulic lifters - hot caustic soak.
Hydraulic lifters are hand washed with spray carb cleaner.
Steel rocker springs - soaked in a hot caustic vat.
Crankshafts can be soaked in hot caustic vat, later they can be wire wheel buffed or bead blasted. Heat cleaning is another option.
Camshafts can be cleaned the same as cranks with the exception of the bead blasting process.
Rockers - may be cleaned in steel media tumbler for 10-15 minutes or may be cleaned in a spray washer or soak tank. (Many shops recommend that aluminum rockers should be soaked in a non-caustic hot detergent vat).
Valve springs - cleaned in a media tumbler with solvent or spray wash or soak tank.