Special Maintenance Tips from the Experts ..
Please remember that extending the life of your engine, machinery and oils reduces your Environmental Impact .. sometimes quite a lot.
Do these 3 simple tests and you’ll get more life out of your engine, especially diesels.
1) Finger / thumb test:
When you next check the dipstick, rub some of the engine oil between your thumb and forefinger. Then wipe it off. The pores of your skin should be left looking nice and clean. BUT if the oil has blackened your finger prints, you’ve got a problem .. the oil cleaning ability is exhausted! You should change the oil immediately. Your engine is accumulating sludge, (black abrasive soot) is causing excess wear!
Here’s what to do. Change your engine oil and filter immediately and do this finger/thumb check frequently. Ensure air filters and fuel injectors are clean. Ensure fuel delivery, timing and valve clearance are correct and check that the turbocharger, governor, intercooler are working properly. Avoid excessive idling and light work.
Bear in mind that the feel of the engine oil is not the “be all and end all” to determining whether it’s still OK. But if it doesn’t feel OK, then it will not be fit for further service. Compare this with new oil of the same type and grade as you are using. Oil will eventually feel thinner and less oily than new oil. This could be from fuel diluting the oil or “shearing effects” on the oil itself from prolonged service reducing the oil viscosity. Always make a note of the oil discoloration. The darker it is, the more contaminants it holds and the less its ability to protect your engine .. which leads to the next simple “Oil Spot Test” below.
Petrol engines do not suffer from the same degree of soot as diesels, but you should still be able to see and feel when the engine oil needs replacing.
2) Oil Spot Test .. simple oil science anyone can do:
All you need is a piece of ordinary blotting paper for this test. Place 1 drop only of used oil (usually engine oil) onto the blotting paper. It’s a good idea to also compare it with the clean oil of the same type, until you learn what to look for. Wait for the oil to migrate sideways through the blotting paper. It may take several hours to fully stabilize. Hot oil will migrate faster. As the oil migrates, it carries with it contaminants which may not move as fast as the oil body. Ideally, the contaminant band should migrate with the oil, to leave a fairly even discoloration. Both total contaminant load and particle size of the contaminants have a bearing on the pattern formed. When the oil is too heavily contaminated, the contaminants clump together and do not migrate easily with the oil front, or alternatively they may migrate in a very heavy even pattern. In each case, it indicates that the despersancy power of the oil is exhausted and deposits will be forming throughout your engine. In addition, abrasive wear from the soot will be occurring at an accelerated rate.
Here’s what to do. Change your engine oil and filter immediately and do this oil spot check frequently. Ensure air filters and fuel injectors are clean. Ensure fuel delivery, timing and valve clearance are correct and check that the turbocharger, governor, intercooler are right. Avoid excessive idling and light work.
3) Oil Spatter Test. This test is very useful if you suspect water contamination in your engine oil (eg slight loss of coolant without outward signs of leaks). A milky appearance of the oil will confirm a substantial amount of water content. However, if there is no visual sign of water in the oil, you can try this test. We suggest that you use eye protection doing this test.
How clean is your engine internally?
You wouldn’t really know for sure how clean your engine is internally, unless you took it apart. For this reason, it’s a good idea to periodically give it a flush out, say once every 3-4 engine oil and filter changes.
If your engine oil and filter have not been changed as frequently as they should, then the Finger / Thumb test and the Oil Spot test should give you an idea of how internally clean your engine might be.
In some engine types (eg Japanese indirect injection diesels) and any diesel engine that thickens and blackens the oil quickly after an oil change, a flushing oil concentrate should be added prior to each engine oil change.
An idea of the cleanliness of combustion chambers can often be gained by looking at sparking plug deposits and fuel injector tip deposits. It is sometimes possible to view, with the aid of a torch, the piston crown through the injector (direct injection diesels) or spark plug hole. Removing a glow plug from a diesel engine will also give you an idea of combustion chamber deposits. Sludge will often settle around valve rockers, so it can be useful to remove the rocker cover for a visual inspection.
An internally clean engine is paramount to engine longevity.