Lab tests of RV lubricant and coolant samples reveal much about motorhome health.
By Mark Quasius, F333630
It’s common for fluid analysis to be performed on expensive, heavy-industrial equipment. An oil or coolant sample is sent to a laboratory where it is scientifically analyzed to determine what is happening inside the engine or certain components. But what about motorhomes? Are there benefits to analyzing an RV’s engine oil and coolant? Or will the information be filed away and have no practical use?
For the answers, I turned to a respected authority in this field, Tom Johnson, president and founder of JG Lubricant Services LLC in Plainfield, Indiana. He previously was a transmission fluids engineer at GM Powertrain and Allison Transmission and was involved in the development, testing, and approval of TranSynd, the synthetic transmission fluid widely used in RVs and trucks. JG Lubricant Services provides fleet managers and maintenance directors the scientific data needed to fine-tune their maintenance programs and keep their vehicles in good working order.
Benefits Of Fluid Analysis
Engine oil is a common lubricant, of course, but axles, fan drive gear cases, and other components also require lubricants in the form of gear lube. A scientific lubricant analysis can reveal much about an engine or component, as well as the condition of the oil itself.
Fuel dilution of a lubricant may indicate incomplete combustion or a faulty fuel system. Water content, soot, and system debris also can be tested. Other tests check for oxidation, the presence of acids, as well as the lubricant’s ability to hold its original viscosity. Many tests can reveal the beginning of a larger issue, such as excessive wear on the crankshaft bearings or other engine parts.
Tests also may reveal something about the operation of the engine. Excessive water content may indicate that the engine never warms up, allowing crankcase condensation to form. As the engine or component begins to wear from use, various materials are shed and held in the lubricant. An oil analysis can point to a potentially expensive problem while it’s still in the early stages. Think of such analysis as health care for your RV.
In addition to monitoring an engine’s health, lubricant analysis also reveals important data about the lubricant itself. All lubricants have a definite life cycle. The owners manual spells out recommended service schedules based on average usage, but that may not match your needs. The recommended service schedule should never be exceeded while a vehicle is under the manufacturer’s warranty, but once the warranty ends, service schedules perhaps can be extended based on accurate data from laboratory-tested samples. In some cases, it might be necessary to shorten a service interval or to change to a better lubricant, possibly a synthetic. Either way, a lubricant analysis can provide information about the RV engine, transmission, generator, cooling systems (of both the main engine and generator), and hydraulic systems.
Lab tests also can be performed on engine and generator coolants, which may help avoid engine downtime, expensive repairs, or failures. A basic hydrometer measures the freeze point of antifreeze, but it won’t reveal the boiling point, the particles present in the coolant, or its pH. Coolant analysis provides information about corrosion metals, nonmagnetic precipitates, nitrite, glycol, total hardness, and a host of other properties. The analysis can determine whether the coolant can continue to perform its job, whether foreign particles are entering the system, and whether the cooling system is gradually eroding as a result of inadequate protection. Cooling system test kits also can be used to measure the performance of boiler antifreeze in hydronic heating systems, such as Aqua-Hot or Oasis.
Do-it-yourself testing kits are available for analyzing oil and for testing coolant, but I don’t recommend them. The best testing is done in a lab that runs samples through a battery of tests to get detailed, accurate results. Coolant test strips can be purchased and used to test pH, supplemental coolant additives (SCA) concentration, and freeze points, but the strips have a limited shelf life and do not provide detailed information about impending cooling system problems.
The labs at JG Lubricant Services are certified by the International Organization for Standardization under the ISO 17025 standard, which means that quality control and accuracy are equal to that of a medical laboratory.
Using The Kit
Consistency is a key to lubricant and coolant analysis. Analyzing a single sample shows what is in the lubricant, but sampling at regular intervals — typically at an annual service — reveals a pattern of what is happening in a motorhome’s components.
The process begins by purchasing a kit from a vendor. Most lubricant test kits can be used for engine oil as well as transmission fluid, while a second kit is designed specifically for coolants. You’ll most likely want to test the generator’s engine and coolant as well, so consider buying kits in packs of three to save money.
JG Lubricant Services sells its Basic Oil Analysis Kit for $20.99. I recommend motorhome owners choose the Advanced Oil Analysis Kit, which costs $26.95; it not only covers basic oil analysis but also can test transmission and gear box fluids. The typical RV owner won’t need the Ultimate Oil Analysis Kit, which costs $40.61 and is designed for heavy-duty fleet analysis. JG’s price for a coolant analysis kit is $34.58. Kit prices cover lab work and processing.
A kit includes a jar to hold the sample, a short piece of tubing, a registration tag, and a shipping bag. To draw a sample, you’ll need a small hand vacuum pump (which JG also sells); this ensures a more consistent sample than taking the sediment from the bottom of the oil pan.
The kit also includes the necessary labels and forms, so the sample is ready to send to the laboratory. After the laboratory analyzes the sample, the results are returned to the owner within 24 to 48 hours.
To obtain an engine oil sample, first run the engine a minimum of 10 minutes. This allows the warm oil to freely flow through the engine and stir up sediment. The goal is a representative sample. Attach one end of the plastic tubing that came with the kit to the vacuum pump and insert the other end down through the dipstick into the crankcase. Attach the sample bottle to the other end of the pump and work the handle to draw the sample into the jar. Fill the jar about two-thirds full, remove it from the pump, and replace the jar’s cap. Dispose of the plastic tubing and clean the pump’s O-ring cavity with a paper towel before returning the pump to its storage container.
It’s also possible to obtain a representative oil sample from the drain plug while changing the oil, but this method can be messy. If you go this route, collect the sample when half of the used oil has drained from the pan.
Detach the tracking code from the registration form and stick it to the outside of the jar. The jar goes into the return shipping bag, along with the filled-out sample information form. Then send the bag to the closest laboratory.
The process is similar when taking a coolant sample. Run the vehicle for at least a half hour to heat the coolant and allow it to circulate. This time, the coolant pump is used to draw a sample from the radiator or coolant reservoir. Once again, use a fresh bottle and piece of tubing to procure a pure sample. Never reuse tubing.
Coolant test kits also can be used to sample source water. Mr. Johnson recommends that RV owners always use a 50/50 premix coolant. That way, the coolant does not get contaminated with excess minerals from a hard-water source.
Videos that demonstrate how to obtain samples of engine oil, coolant, and RV generator engine oil are posted on the JG Lubricant Services website, www.jglubricantservices.com. Click on the “RV” tab at the top of the home page, and then look for “How-to Videos.”
A periodic analysis of the lubricants and coolant in a motorhome provides important information about what’s happening in the engine, transmission, generator, and cooling systems. Knowledge is power. When the data shows that lubricants and coolants are not performing as desired, or there are signs of excessive internal part wear, changes can be made to your service schedule and problems can be corrected before they become costly.
JG Lubricant Services LLC
P.O. Box 662
Plainfield, IN 46168