It's best if you do, but if you've used a good quality assembly lube you MIGHT be okay.
Personally, I'd never install an engine where I haven't primed the oil pump.
Wouldnt you like to know.
put in new piston rings or rebuild kit for the entire motor
That is a lubricant, specially an oil for motor vehicles
if it does not leak oil, but the oil level dropps(or you have smoke, white or blue). on these motors, the valve stem seals lie to go out, and that's cheaper than a whole rebuild. start your motor, and remove the oil fill cap. if alot of smoke starts to come out, you need a rebuild. if little or no smoke comes out, your motor is good, and you need new valve stem seals
i believe they have an oil injection system on these engines
To prime the oil pump on most cars all you need to do is turn the motor over without it firing, disconnect the coil and turn the key, this will prime the pump.
To purge the motor with oil on a fresh rebuild of a 1980 Shovelhead before starting, first remove the spark plugs and then use an oil pump priming tool or a drill with an appropriate adapter to circulate oil through the engine. This will help ensure that oil reaches all critical components, including bearings and the oil pump. After priming, inspect for any leaks, re-install the spark plugs, and then start the engine while monitoring oil pressure to ensure proper lubrication.
Short of it...Rebuild your motor. Most likely the cause of it is the piston rings need to be changed but it could be worse. Rebuilding the motor is the easiest solution and saves a lot of hassles
when puting a oil pump in a motor u always need to prime the pump manually and check it screen
Flush the system immediately and install the correct fluid. Oil is too thick for the PS system.
...technically, no you won't need to replace the motor. What will happen is that all the moving parts that depend on fresh oil for lubrication will suffer from its absence, with increased wear (same if there is oil but it's overdue for replacement due to thermal breakdown or contamination). But technically assuming that it won't turn over, a motor rebuild would probably be in order. Not certainly because it might not turn over for other reasons. It's a lot cheaper to get a working motor and have it put in your car, though, because a motor can have hundreds of thousands of miles on it and still run. A rebuild can easily cost $2k or more to have it done by a competent mechanic.
A easy way is to either crank the engine over with the starter motor, without the coil being plugged in until oil pressure is obtained.If rebuilding an engine and you want to prime before completion just squirt oil into the oil pickup while the engine is upside down and turn the pump drive to lube the internals. This will help get pressure faster when it comes time to prime with starter motor when engine is in vehicle.