This guy says pre-filling an oil filter is bad and that all manufacturers say so.

Would it be possible that the muffler had weld through primer??? I cringe whenever he uses the small impact driver on battery terminals...I mean you can do it if you are careful...but still...
No, it was a Cherry Bomb with the red paint. I watched that one waiting for him to sand the rust off and remove the paint. It never happened. To be fair, he did say he was no welder, so I guess that job proved it. 😎
 
I always clean the threads and inspect the inside of the filter.
I was talking to a guy who once found a cigarette but in a filter
 
Any debris that might get in the engine through the oil fill cap would be caught by the filter (or oil pick-up screen if that big) before hitting sensitive parts like bearings. It might still get in something in the valve train and cause damage, or damage the oil pump. So always clean around the oil fill cap if required before removing the cap.

I think Cat or Cummings (don't recall for sure) does recommend pre-filling the oil filter. Of course some of those filters are huge.

I always pre-fill, even vertical filters mounted base down (my Tacoma). On that one, I soak as much oil into the media as possible without it making any mess when installing the filter.
The Cummins trainer that taught the classes I took said to fill the oil filter since it had no priming procedure and put the fuel filters on dry since they could be primed while on the truck.
 
I have been pre filling oil filters since I did my first oil change in 1967. In fact I have never not done it. I have never once experienced a negative issue because of it. I do see the oil pressure gauge rise much sooner after starting, than it would by not pre filling the filter. (Or in the case of an oil light, see it go out much sooner). Which is the object of the whole exercise.

There are people who can find a negative in most everything. Most of this type of reasoning can be eliminated with a simple application of common sense. This is one of them.
My 2 cents, master certified mechanics fill their filters when changing their own 🛢 oil. Nuff said
 
IMO it is a waste of time to prefill an oil filter. It only takes about 2 seconds for the filter to fill and the system to pressurize after the engine is started. The engine is not going to be damaged by this, particularly in view of the fact that the engine is not under a load when it is started, and all of the bearings still have some oil in them from having been recently run (they are not dry). I don't recommend that anybody try this, but you can idle an engine without any oil in it for a substantial length of time without causing any major damage, but it will quickly seize as soon as you put a load on it.
 
The new gasoline or none diesel engines I built I always pre-primed them. They ALL had mechanical oil pressure gauges connected during that process. In the rare exception the oil pressure was developed within seconds using an oil primer and hand drill. In the case no easy way to use a oil primer, removing the spark plugs and spinning the engine developed Oil pressure within seconds These were on new engine with EMPTY new oil filters.
On a normally run engine if oil pressure is not developed within a few second after the engine starts you get a RED engine light. An engine in service still has oil to protect it during the first few seconds of start up to fill the dry/empty oil filter. It takes a few minutes to really harm an engine that has no oil pressure unless the engine is used in high RPM immediately after you start up. Who does that? And who continues to run the engine when the RED engine light is on?
I have rarely seen any shop of DIY that is completely sanitary during a routine oil change. I had a engine assembly clean room and I still needed to clean the "clean room" from time to time for dust. LOL
 
IMO it is a waste of time to prefill an oil filter. It only takes about 2 seconds for the filter to fill and the system to pressurize after the engine is started. The engine is not going to be damaged by this, particularly in view of the fact that the engine is not under a load when it is started, and all of the bearings still have some oil in them from having been recently run (they are not dry). I don't recommend that anybody try this, but you can idle an engine without any oil in it for a substantial length of time without causing any major damage, but it will quickly seize as soon as you put a load on it.

Counterpoint, it's not harming it to be prefilled assuming no contamination, and prefilling only takes seconds to do so. If you can do it without spilling it.
 
IMO it is a waste of time to prefill an oil filter. It only takes about 2 seconds for the filter to fill and the system to pressurize after the engine is started. The engine is not going to be damaged by this, particularly in view of the fact that the engine is not under a load when it is started, and all of the bearings still have some oil in them from having been recently run (they are not dry). I don't recommend that anybody try this, but you can idle an engine without any oil in it for a substantial length of time without causing any major damage, but it will quickly seize as soon as you put a load on it.
Reminds me when I saw a couple of young guys who didn't know much about cars do an oil change - think it was the first car they ever owned. They were doing the work on top of an incline for some reason, so they decided to roll the car down the incline to a more level spot and drain the oil. Then they fire up the engine and drive it back up the incline with no oil in it - I was standing there going :oops:. The engine was starting to make some ticking and knocking noises by the time they got it back up to where they wanted to finish the job - rods and mains were probably not happy. That probably did some slight damage/wear on the bearings, but it seemed to still run OK after new oil was put into it. I told them that what they just did wasn't good for the engine and explained why, and they obviously had zero clue about how engines work by the look on their faces.
 
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I got mixed feelings on this guy, he's a bit of a hack in some of the videos, but there aren't many folks in shops that would put rod bearings in a knocking engine left...
 
Another thing is the size of the filter itself. The filter on my Toyota is tiny compared to the full size PH-8A on my 5.0 Ford V-8. Which takes much longer to fill. The less an engine runs without oil pressure, the better. It takes almost no time to pre fill a filter with fresh oil. So why not do it?
 
I understand the reason to pre-fill a vertically mounted filter, but how do I pre-fill my filter??
screen-shot-2021-08-26-at-6-07-44-pm-jpg.68578
:ROFLMAO::ROFLMAO::ROFLMAO:
 
Does that actually work??
i am also with the pre-fill group. As long as everything is clean, I see no harm in this practice.
Yes it does.
Is your vehicles engines fuel injection system controlled by the PCM? I'm guessing when the gas pedal is floored it shuts down the fuel system?
Someone with more knowledge want to help me out here? :unsure: 🤷‍♂️
 
Priming a filter is usually not bad and kind of fun in a " I have time to burn " scenario.

Priming a filter from any unfiltered source is not best practice.

All kinds of things occur in manufacturing and distribution.

Oil from a drum may contain a partial thread from the bung that didnt clean out..
What if manufacturing accidentally contaminated a small batch of jugs?

There numerous contamination opportunities
 
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