Talk Morgan Forums Community Vehicle Talk (non-Morgan) Ever worried about oil?

Found this on YT .... has an annoying AI translating voice but interesting if you ever a shakey hand and worry you slightly overfilled your sump. Bit of fun rather than science but interesting nevertheless


[video:youtube]http://www.youtube.comwatch?v=/VaTbfvzNbxQ?si=qBx8pxqCNsnOPEPK[/video]




K

I only worry when there is a large pool of it under one of my motors!

Thanks. I did a car maintenance course for NT volunteers last winter& one lady admitted adding 5 l of oil when the oil warning light came on. It wrecked the engine.
Another added frying oil as she ad no motor oil. That one ran OK & they sold it on!

Not universal ... I know landrover diesels are sensitive to overfilling (hence a big spat between LR and the army a while back) ... and the effect of foamy oil if the engine was run for longer ... a bit of fun rather than science but interesting to actually see inside the engine as it runs.

K

Some early engines used to have a sort of dipper that was cast into the end of the conrod big end, it was designed to pick up some oil from the sump, often called splash lubrication

As seen in your lawn mower

As does this big, old (but incredibly long-lived and reliable) dinosaur .... crank dips into the oil in the sump splashing it everywhere ... must work as it's still going 80 years and counting 🙂




Though I think it's 'splash' lubrication (unless you're taking the p*ss pf course!! 😁)

K

Oops, it's been a long day Keith, now corrected

Engine lubrication has developed over the years starting with a man with an oil can feeling each bearing for noticeable heat and lubing accordingly. Glass oil reservoirs positioned directly over bearings followed. Then on larger engines a central high mounted oil chest immediately above a series of glass monitor tubes which were piped to individual bearings to allow gravity fed supply. The flow rate from oil chest measured by drips was controlled by individual valves. The positive loss waste oil was often burnt in the case of two stroke engines particularly if lubricant was mixed with fuel, or drained off at the end of engine use.

Wet sumped pressure pumped systems then replaced gravity feeds as power outputs increased requiring lubrication on greater bearing loads to prevent the oil film between moving parts being broken. Pressures were little more than a few psi though for the generous bearing surfaces and often just enough to allow oil to reach upper parts of engine. My 1936 Lister diesel required only 8 -15 psi at running rpm for example and barely 5 psi at idle. Being a marine diesel it also had a scavenge pump in the shallow sump to return oil to a remote large oil tank located high enough to guarantee a head of oil to pressure pump no matter how heavy the sea. Such dry sump systems are used today in race, some performance cars and older bikes of course for similar reasons.

The big end mounted dipper was an answer for slow revving engines often stationary and widely adopted by Lister to allow cylinder bore lubrication and possibly piston cooling from underneath. In many cases it didn't replace pressure lubrication still required elsewhere. Similarly my 1945 Guzzi single turns in such a direction to sling oil from pressure fed big end onto upper surface of horizontal cylinder.

Little thought was given to oil filtration on earlier engines. Perhaps a fine mesh gauze but little else, relying instead on regular oil changes. Important in such cases that non or low detergent oil is used in such allowing wear debris to fall to bottom of sump out of harms way rather than being encapsulated as with modern oils to be trapped by a full flow filter.

My 1936 500cc BSA Q8 Empire Star and the 1935 500cc BSA W35-7 have split port single cylinder engines, both utilize a sort of half way house design between vintage and more modern oil delivery systems. The oil is pumped to the engine big end via a crank driven gear pump, the flow rate can be manually adjusted. However, there is no pump to recover the oil back to the oil tank. The oil tank is cast into the engine crankcase at the front of the engine, as the crankshaft rotates the (large) crank webs picks up the oil from the bottom of the crankcase, the oil is then scraped off the crank by a knife edge design at the top of the crankcase oil tank, thus returning the oil back to the oil tank. It works well. The only other direct gear pump oil supply is to the rear inlet valve area, which has it own cover, the front exhaust valve is exposed and has to be lubricated by hand periodically. All other internal engine lubrication is by splash feed.