What is crank case oil?
engine oil (crankcase oil, motor oil) – oil carried in the crankcase, sump, or oil pan of a reciprocating internal combustion engine to lubricate all major engine parts; also used in reciprocating compressors and in steam engines of crankcase design.
Can a high crankcase pressure cause an oil leak?
Manuals can be found at the manufacturers website.** An abnormally high crankcase pressure can cause oil leaks. The engine crankcase is designed to operate below atmospheric pressure, and the breather valve or pcv (positive crankcase ventilation) valve is the device used to keep crankcase pressure below atmospheric pressure.
What do you need to know about crankcases?
Frame and running gear (Crankcase and crosshead). Typical crankcase condition monitoring and safety devices are: Relief device—To prevent crankcase breakage in the event of explosion (caused by entrance of process gas into the crankcase). Breather vent—To allow removal of entrained air from the lube oil.
What should the crankcase pressure be in an engine?
The engine crankcase is designed to operate below atmospheric pressure, and the breather valve or pcv (positive crankcase ventilation) valve is the device used to keep crankcase pressure below atmospheric pressure.
How is stiffness achieved in a crankcase?
Crankcase is a nodular cast iron design specified for resilient or rigid mounting. Stiffness in bending and in torsion is achieved by strong base strips and by integration of the boost air and camshaft casings; the transverse bolting of the basic cover also contributes.
What causes oil to build up in crank case?
The plastic tubing and fittings get extremely brittle with age and also becomes restricted internally due to oil deposits and sludge forming inside the tubing. The restricted breather flow results in excessive crank case pressure, which in turn begins to force oil past seals.
Is there any oil in the crankcase breather?
If you don’t overfill the oil tank you’ll never see more than a few ccs of oil in there even after a 200-mile thrash. It’s possible (but unlikely) that all the oil returns by the crankcase breather at high engine speeds, but as long as it gets back in the tank I’m not unduly concerned.
Why is oil leaking out of my Norton crankcase?
As you may be aware, the Norton motor acts like a giant air compressor during running. As the pistons go up and down the air within the case also expands and contracts. If the breather is not functioning properly oil will almost certainly leak out of the cracks and crevices.
What’s the problem with the Norton combat crankcase?
More recently someone on Brit-Iron or NOC-L referred to a related design flaw in the Combat crankcase. He indicated that the oil pickup for the return pump was too far forward, and that by drilling new holes into an existing return oil passage at the rear of the case, the scavenging of oil from the crankcase would be greatly improved.