Never Prefill oil filters!

[DoubleWasp]

That is the thing, there actually are Manuel's that state to pre-fill an oil filter before starting the engine.

Important? I'm not even sure that that was a topic during this thread. It absolutely wasn't the topic presented by the OP.

Worthwhile? That's going to be far more of a subjective statement.

The topic at hand, was whether or not pre filling a filter is detrimental. There has been absolutely no information presented to support it being a problem.

 

[StevieC]

My point was that if it was beneficial or detrimental they would have a statement either way.

I have not encountered a manual that says to fill it first, and I bet you those engines where this is stated in their manuals are just fine at the quick lube places where it isn't being done.
I'm not suggesting not to do it if the manual says to, just that it isn't happening and we don't hear horror stories about it.

 

[Pinoak]

Originally Posted by SubieRubyRoo
Originally Posted by Pinoak
I shake but never more than 3 times.


If you shake it more than 3 times, you're just playing with it.

exactly

 

[DoubleWasp]

Originally Posted by StevieC
My point was that if it was beneficial or detrimental they would have a statement either way.

I have not encountered a manual that says to fill it first, and I bet you those engines where this is stated in their manuals are just fine at the quick lube places where it isn't being done.
I'm not suggesting not to do it if the manual says to, just that it isn't happening and we don't hear horror stories about it.


I'll agree it doesn't make a difference either way.

 

[Uphill_Both_Ways]

Originally Posted by Charlie2015
I never prefill oil filters. I rub the old filter and the new filter together to lube the gasket, too...

i used to rub only the new filter in case a genie would pop out.

But I stopped doing that after a particularly ugly Mr. Goodwrench appeared in a puff of blue smoke and charged me flat-rate $120 an hour for the oil change.
Originally Posted by ZeeOSix
Originally Posted by PimTac

"I have no problem pre-filling oil filters. I dont shake the bottle just in case any heavy stuff has settled out in the bottle. "
I hadn't heard this one before. Should we shake or not shake?

I can start another dumb thread.


I'm sure you've seen the many threads in the PC oil forum about sediments in the bottom of oil jugs. If not, start reading more forms on BITOG.

I always vigorously shake the new, pre-filled filter. That way I can see and remove any dirt from the dust storms that blew into the manufacturing plant.

 

[WellOiled]

Originally Posted by advocate
This is why I prime my vehicles before starting them after an oil change. Simply put the gas pedal to the floor. This shuts off fuel in Ford's since the 1990's or so. Crank till the oil pressure gauge is in the normal range. Then I'll start it.

Advocate - this is the best solution for a Ford that has been posted. Hopefully the Ranger is setup this way.

 

[StevieC]

Originally Posted by Uphill_Both_Ways
i used to rub only the new filter in case a genie would pop out.
But I stopped doing that after a particularly ugly Mr. Goodwrench appeared in a puff of blue smoke and charged me flat-rate $120 an hour for the oil change.

 

[ZeeOSix]

Originally Posted by Uphill_Both_Ways
I always vigorously shake the new, pre-filled filter. That way I can see and remove any dirt from the dust storms that blew into the manufacturing plant.


A shop vac on the center tube hole works better.

 

[y_p_w]

Sure. Because the overhead camshafts (visible from the fill hole) in the cars I've worked on were only an optical illusion. I wasn't actually pouring oil straight from the bottle onto the camshaft.

Seriously though - I don't specifically "prefill" in any meaningful way if the filter is mounted horizontally. My WRX filter is mounted base up - actually the mount is on the oil cooler. However, every Honda-made car I've changed oil was mounted closer to horizontal. Maybe tilted a little bit up. If I did anything it was to wet the filter on the premise that it might take a split second less time before it start flowing - as long as it's not absorbing oil into dry media.

And how do you do it with the new filters that are mounted base down? Found this for a newer Subaru:

 

[WellOiled]

Originally Posted by y_p_w
Sure. Because the overhead camshafts (visible from the fill hole) in the cars I've worked on were only an optical illusion. I wasn't actually pouring oil straight from the bottle onto the camshaft.

Seriously though - I don't specifically "prefill" in any meaningful way if the filter is mounted horizontally. My WRX filter is mounted base up - actually the mount is on the oil cooler. However, every Honda-made car I've changed oil was mounted closer to horizontal. Maybe tilted a little bit up. If I did anything it was to wet the filter on the premise that it might take a split second less time before it start flowing - as long as it's not absorbing oil into dry media.

And how do you do it with the new filters that are mounted base down? Found this for a newer Subaru:

Using a sharp punch, punch a small hole in the dome end. Oil should drain out of the filter. Remove, clean and replace. Do a cut & post on the used filter.

 

[CharBaby]

Originally Posted by SubieRubyRoo
Originally Posted by Pinoak
I shake but never more than 3 times.


If you shake it more than 3 times, you're just playing with it.


Stirred, not shaken.

 

[Dallas69]

Totally unnecessary to prefill a filter except for vehicles that do require it.
Just some ocd nonsense from someone with a history of it.

 

[WhizkidTN]

Well that discussion went to "11" pretty quickly!

My Optima's oil filter position (straight up) allows me to fully pre-fill my oil filter which I do. I shake my 5qt jug of oil as well. And I DO play with it!
I like seeing my oil pressure light go out near instantly upon starting her up.

I do wish Fram would seal their filters with plastic (like my OEM does, at least the Ultra's anyway) and not just the quality seal on the box but I always inspect them with a strong light anyway prior to filling them with oil - "just in case" I bought a dud.

What was the name of the prolific BITOG poster who always advocated for this and he passed about a year or two ago? He seemed to be a pretty nice guy.

 

[Patman]

Originally Posted by StevieC
My point was that if it was beneficial or detrimental they would have a statement either way.



For the longest time I always pre filled my oil filters before putting them on, but now I don't bother as I don't think it will make a difference either way, so by NOT doing it anymore it saves me a messy step at oil change time. I still make sure to put some fresh oil on the gasket though, I never put the filter on an engine without that important step.

 

[PimTac]

I prefill my filter out of habit but with the Mazda the filter is So small it probably will fill up in a flash. So it might be unnecessary.

 

[StevieC]

Originally Posted by Patman
Originally Posted by StevieC
My point was that if it was beneficial or detrimental they would have a statement either way.



For the longest time I always pre filled my oil filters before putting them on, but now I don't bother as I don't think it will make a difference either way, so by NOT doing it anymore it saves me a messy step at oil change time. I still make sure to put some fresh oil on the gasket though, I never put the filter on an engine without that important step.

Especially on a CRV where you can't easily get a belt wrench around the filter. My father inlaw did the change and then I did the following one and guess who had to try and get the filter off after 1 year after it had been put on dry. THIS GUY!

Let me tell you how I mangled that filter.

 

[DoubleWasp]

Originally Posted by WhizkidTN
Well that discussion went to "11" pretty quickly!

My Optima's oil filter position (straight up) allows me to fully pre-fill my oil filter which I do. I shake my 5qt jug of oil as well. And I DO play with it!
I like seeing my oil pressure light go out near instantly upon starting her up.

I do wish Fram would seal their filters with plastic (like my OEM does, at least the Ultra's anyway) and not just the quality seal on the box but I always inspect them with a strong light anyway prior to filling them with oil - "just in case" I bought a dud.

What was the name of the prolific BITOG poster who always advocated for this and he passed about a year or two ago? He seemed to be a pretty nice guy.



You'd love the filter for my car. Not only does it come sealed in plastic, but they actually test it on a rig that pumps oil through it and cap the base end with a hard plastic cover before bagging it.

 

[y_p_w]

Originally Posted by StevieC
Originally Posted by Patman
Originally Posted by StevieC
My point was that if it was beneficial or detrimental they would have a statement either way.



For the longest time I always pre filled my oil filters before putting them on, but now I don't bother as I don't think it will make a difference either way, so by NOT doing it anymore it saves me a messy step at oil change time. I still make sure to put some fresh oil on the gasket though, I never put the filter on an engine without that important step.

Especially on a CRV where you can't easily get a belt wrench around the filter. My father inlaw did the change and then I did the following one and guess who had to try and get the filter off after 1 year after it had been put on dry. THIS GUY!

Let me tell you how I mangled that filter.

Every oil filter I've used has some instructions or a drawing indicating that at least a drop of oil needs to go on the gasket. I mean - who skips that step?

And over the years I've collected a variety of different oil filter removal tools. Some were filter specific cap wrenches and only work on some shapes. Some instructions even say to use a cap wrench to install since they cause little damage to the can. I can't find most of them though.

I had a Lisle metal band wrench and tried using it on my WRX where it frankly was a bad choice. I had no other tool at the time to do it. Also a claw somewhere that was a piece of junk. But the one I use now is a cam-action one for small filters. This may not be the exact model, but mine is similar. It's like a Vise Grip that I can use with a 3/8 socket wrench.

 

[Pinoak]

[You'd love the filter for my car. Not only does it come sealed in plastic, but they actually test it on a rig that pumps oil through it and cap the base end with a hard plastic cover before bagging it.[/quote]

What filter is that?

 

[Shannow]

More BITOG gold....

Facts
* new oil can be very very dirty
* prefilling put the new oil on the engine side of the rock trap
* bypass is closed when the filter is passing air to pre-fill the engine
* the dirty oil that you are emptying into the engine gets to go through the filter first before the bearings
* even at that point IF the filter is in bypass, then some/most of the oil gets through the media.
* prefilling gives you more chance of dropping something bigger down the hole, which another poster has identified with bits of foil.
* there is no metal to metal contact on that start, as there's plenty of oil and tribofilm left from when the engine was running.

Another fact is that I have never seen an automotive maintenance document produced by an OEM that tells one to prefill a filter...would be very interested in seeing one, to make it my first.

Of COURSE manuals telling you not to prefill are not common (the big diesel example cited excepted), as telling you to not to do something that you wouldn't normally do is superfluous:
* don't add coolant to windshield washer fluid
* don't use icepick to clear windscreen.