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Discussion Starter #1
Just wanted to share how I prime the oil system on a 12V. I fill the filter as much as is reasonable and still install it. Remember that the center hole is the outlet so you really should fill it from the outter holes.
Then I put all but 2 quarts in the engine as normal. Then I remove the plug for the main oil pressure regulator, be very careful as this will pop out because of the spring tension of the regulators spring. Using a very clean and strong magnet, (I clean my magnets with a wire brush), remove the spring and then the regulator piston. Using a transmission funnel very slowly I pour the last 2 quarts of oil in here. Your filling the pump and the pickup tube, obviously the oil is not going to stay in there so this should be the very last thing to do before cranking the engine. If there is any chance it may start you will need to unplug the fuel solenoid. Reassemble the regulator and lube the oring on the plug/cap before installing. I cranked the engine 30 seconds and had full oil pressure at about 15 seconds.
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Seems like a lot of extra work to me. You do this after every oil drain?
 
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I remember years ago it was recommended not to even prefill the filter due to the chance of a piece of the foil getting into the clean side. Once there, it could wind up trashing a piston cooling nozzle. I still prefill mine, but super careful when doing so.
 

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Now I know why your post count is so high.
I don't think you do, but that is another conversation.

By not answering the question you force me to make another post? Why do you do the exercise? The pump gets "primed" virtually ever time it gets started. During an initial start after major maintenance it gets primed while cranking the engine to purge air out of the injector lines. I don't see any point in doing what you do. I also don't see any point in making sure the oil is poured into the outer holes. I'm assuming you are using new clean oil. What exactly are you afraid of?
 

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Discussion Starter #7
I don't post a lot because I don't have time for this. But regardless.
I thought it was obvious by my post and the pictures that this was a fresh rebuild. Everyone has their own procedures for a fresh engine start. These engines in my experience are hard to get the oil pump primed. Some people are ok with just cranking the engine over, I'm not, no matter how well lubed you are upon assembly it's going to be gone by the time the pump finally starts drawing. I don't care if its a gas or diesel engine, it should be primed before start up or extensive cranking.
Dodge came out with a TSB concerning pre-filling the oil filter because so many engines were burnt after an oil change because of a piece of the foil seal plugging up the piston squirter. Many people like Rotella T4 or T6 engine oil. Next time you empty look in the bottom of the jug. I personally don't worry about it but that is not the prescribed method. Just like filling a fuel filter, your not supposed to fill it using the middle hole. Many shops I have worked at have a machine to fill fuel filters properly. But it really doesn't matter.
These forums are full of keyboard warrior's trying to tear everyone else's post down. I don't come on here much because I have no desire to fight with people. 95% of the assinine comments made from the safety of your keyboard would never be made if you were standing in front of the person you were making them too.
Use the information I have posted, don't use it, kick me off the forum, I really couldn't give 2 shits. I'm not here to prove myself.
 

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I have no trouble with face to face debate and my questions are legitimate. It was you who said "Your filling the pump and the pickup tube, obviously the oil is not going to stay in there so this should be the very last thing to do before cranking the engine." and I agree. Therefore the exercise is pointless IMO because by the time you have reassembled the regulator all the oil has drained into the pan. 15 seconds until oil pressure doesn't sound that impressive to me. Now, if you have a means to prime the entire system I'd love to hear about it. I have a modified distributor from a small block Chevy that I use to pump oil through the system prior to starting and I also have one for a Y block Ford.

I'm well aware of the tin foil deal. Amazingly enough that doesn't happen when you pay attention to the job at hand. I don't use Rotella unless it is on sale so I can't look at the bottom of a jug. Are you saying there are contaminates in new Shell oil? I've never heard of that before.
 
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Well it wasn't clear that this was the 1st start on a rebuilt engine.

The inability to easily prime the oil pump on the Cummins is well known. This is also a common problem on modern gas engines that do not have a distributor.

On the 2 rebuilt common rail Cummins that I have been involved in, we pre-filled the oil filter, poured oil into the turbo oil feed, connected a good quality oil pressure gauge and then disabled the ECM from firing the injectors.
We then cranked the engine with the starter about 10 seconds at a time until we had good oil pressure.

Hardly the best method but it is better IMO than firing the new engine without doing anything.

The Hamilton cams Cummins oil pump primer is an option: Priming pump
Better than nothing but hardly ideal.

On modern gas engines, especially on the common GM LS V8's, many folks are connecting an external oil pump system and then pressure feeding oil into the engine via an oil gallery port.

The days of modifying an old distributor shaft and spinning it with a drill like we all have, doesn't work on all engines!

On a positive note, that is a good looking engine and engine bay on what looks to be an OBS F250!
More pics and info on that truck would interesting also.
 

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While the engine is still on the stand, before I put the timing cover on a fresh rebuild, I install a pump that I pulled the gear off of. I drive the pump with an old 7" air powered angle grinder via a short piece of 5/8" heater hose simply hose clamped on the 5/8" threads of the grinder shaft and clamped on the oil pump shaft (it's close enough to 5/8" to work fine).

Usually primes within seconds and I'll run it until see oil weeping from the rockers (1-2 minutes usually).

I prime the oil systems this way primarily because I am often assembling engines with blocks and bits that didn't come together, but there is always a chance I used the wrong oil cooler gaskets or filter assembly for the block or I missed an oil galley plug somewhere. I'm realistic enough to know I can make a mistake so priming it this way and seeing 50 PSI and oil flowing ensures I didn't miss anything.

When I'm done priming I pull the pump, let it drain in a clean pan for a minute then wrap it in a new heavy plastic bag and put it on the shelf for the next engine.

I don't believe it's a requirement to prime them, but I do it for my own piece of mind knowing it's a 5 minute step that can save a lot of headache if I get the engine in the vehicle or ship it to another country, etc and missed something stupid.
 

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On modern gas engines, especially on the common GM LS V8's, many folks are connecting an external oil pump system and then pressure feeding oil into the engine via an oil gallery port.
While that would certainly work and be ideal, I've done a couple LS's personally and been around at least 10 others and we all just used a good moly assembly lube and fired the engines up with no attempt at priming.

One of those engines (unfortunately or me, it was one of mine) sucked up some water off-roading (operator error, and that operator was me) and bent a connecting rod so the engine had to come back out. This engine had seen 50-60K miles and a lot of WOT mudding time by this point. All the bearing still looked new (but the bottom of one piston was beat to heck by the counterweight of the crankshaft after the connecting rod bent)
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