Not sure what engine you are working on but sometimes you can roll the engine backward and get the gear to disengauge .
No, it will not. Low oil & or pressure will not prevent the engine from starting.
the fuel pressure is around 30psi
There is no ideal pressure. Of course the oil pressure will be higher when the engine is cold. After it is running and at full operating temp, the pressure should read at least 10 lbs while idling. The pressure will be directly related to how many miles are on the engine and the amount of wear. A new engine will have around 40 lbs when hot and running at 2,000 rpms, and around 30 lbs at idle.
Engine oil pressure will vary depending on if the vehicle is in an idle state or not. However, on average, it should be around 40, which is typically half of the gauge.
After starting the engine, the oil pressure rises. The switch changes from either open or closed at a predetermined oil pressure, switching off the warning light. If oil pressure drops during operation, this light should come on, warning you of this dangerous situation for the engine (and your wallet).
Yes, that is possible. Never overfill any engine.
Did you change the fuel filter? Have you checked the fuel pressure regulator?
Could be the TDC Sensor, sometimes called the crankshaft Sensor.
Worn main bearings sometimes knock when cold starting
It means that the oil pressure switch is showing low pressure.
Yes, any piston engine draws air in when the piston move downward on the intake stroke, and as a result does create a lower pressure with respect to the atmospheric pressure around the engine.
A blown head gasket can prevent an engine from starting. A blown head gasket may not provide the pressure needed to get the engine started, and will also allow oil to leak out uncontrollably.
the pressure in the engine will stop it from starting (oh 305's are shite)
there is no oil pressure on a lawn mower it has a splash the oil around inside the engine. There are some small engines with an oil pump. It is mounted inside the engine oil pan.
Bad oil pressure sending unit? Try replacing with a mechanical gauge Excessive engine wear? Do a compression test
What to do before starting auxiliary engine?
High oil pressure is not usually a problem. The relief will open around 100psi on most engines.
Answer 1 - Fluctuating Oil Pressure Gauge IndicationI am not familiar with your particular vehicle, BUT... Usually fluctuating oil pressure during idle indicates that the engine idle speed is fluctuating and may need to be adjusted to manufacturer's specifications. Sometimes, this is an indication of wear in an engine.While the check engine warning lights are ON, indicates that during that time the engine oil pressure is below the manufacturer's recommended "safe" level.Although sustained low oil pressure can damage an engine, during idle, brief, intermittent, low oil pressure excursions do not harm the engine, but do suggest that you have the low oil pressure issue "checked out" by a qualified automotive technician.If this problem occurs at normal driving speeds, then you either are low on oil in the engine, or have other problems which could be hazardous for the health of your engine.
The oil pressure may vary depend on mileage. However, typically on a 1988 GM engine should be around 14.25 ohms or more.
A good practice is to let your engine idle for a few minutes after starting so the oil pressure can build and lube all the internal parts of the engine. A vehicle with turbo should be idled before shutting off to let the turbo cool down.
Hard starting on a fuel injected engine is often caused by low fuel pressure. The fuel pressure should be 45 psi. Low pressure might be caused by a clogged fuel filter or a weak fuel pump. Low pressure can also be caused by leaks in the fuel system.
Oil pressure has to built up. As long as the pressure is normal and the oil level is good. There is no problem.
The fuel pressure regulator maintains a constant predetermined fuel pressure regardless of engine RPMs.