Fill oil filter with oil well before screwing on horizontally?

General Discussion
1

The Letsuck RX350h engine has a horizontal oil filter.
After an oil change there is no oil in the oil filter when the engine is firstarted.
(Is the oil first pumped from the sump to the engine and then through the filter?)

Would filling the oil filter well in advance allow oil to permeate the filter media and at least fill the void between the can and filter?

I shall try it and report.

Thank you.

2

My Mazdas and Fords all have a filter mount that has the open end of the filter facing straight up. I prefill those filters at each oil change before installing them as it allows full oil flow more quickly when I start the car. The one Nissan we own has a sideways facing filter so there is nothing I can do but leave it empty when I install it.

I don’t think it’s a huge issue if you fill the filter or not, but it doesn’t cost anything and it makes me feel better about the first start after the oil change.

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3

When able, I always put some oil in the new filter as well as put fresh oil on the gasket before installing…

Oil should flow as follows, pan, pickup screen, oil pump (bypass varies), filter and then pumped though the engine…

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4

Be aware that any oil you pour inside a new filter goes directly into the engine when you start the engine, doesn’t go through the filter first. So it must be perfectly clean.

5

George, I don’t know where you are getting your oil from and why you think it would be dirty but As long as you open the oil cap from a sealed bottle and pour it into the filter and then engine there is no problem, EVERY mechanic that I know (in person) has been doing this for a very long time, me 35+ years, couple old buddy’s, since the 60’s, and many many more, and NONE of us nor have I ever heard of anyone ever having an issue with adding oil to the filter…

Now if you DON’T know how to put the cap back on a bottle when done with it, then that is on you…
I also don’t use oil 2nd hand, I always put the cap back on the bottle rather it be empty or some left over, so I will never have an issue with adding oil to a new filter…
I also retired from a very large company after 17 years and if anyone had ever had a problem in the company that caused engine failure, every shop (2,200+ shops company wide) would know about it…

BTW, anytime you replace a torque converter, you have to add about a quart of ATF, the fluid goes through the converter and then the transmission before finally going through the filter… Transmissions are way more sensitive to dirt, a human hair can stick a spool valve and burn up an entire transmission… I have never heard of anyone filtering the new ATF before adding it to the converter from adding straight from the bottle…

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6

If you prefer that method, it is ok by me. I concur, it seems pretty unlikely a major oil supplier would allow any foreign matter into the inside of one of their containers. Similar to food products, seldom find any foreign matter inside those containers either.

7

Years ago we could buy filtered used motor oil for 10¢/qt. or something.
Can’t remember if it even had a viscosity rating.
Came in quart cans, I recall.

8

I’ve never done it. Many vehicles it’s even IMPOSSIBLE to. My 05 4runner is just one example. The filter is up inside the engine bay and sits upside-down. Never had an engine problem with any of my vehicles - even after 300k miles.

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