[LeoGeo]

After it sits for a few days, my 97 will have a second or so of valve clatter and the oil pressure light will stay on for about 2 seconds when it's first started.

When I changed the oil in it, the filter looked empty. It was a cheap filter the previous owner installed, so I replaced it with Bosch. Bosch has never seemed to have problems with the anti-drainback valve on other cars with similarly mounted filters I've owned. It didn't seem to change much; there is less start-up noise, mostly due to fresh oil, but the oil filter still drains down. When I pull it off after sitting for a day or two, none even drips out.

Researching online, there seems to be a “oil cooler relief valve” that the filter screws into? Would this going bad allow oil to drain back into the sump? I'm kinda at a loss here, it really doesn't seem like the engine should be needing to refill a dry oil filter after every start up.

(not my car, images mooched online)

 

[LugNut]

Try a genuine Toyota filter for the RAV4.1/3SFE. Let us know if that makes a difference.

The long-ish delay could also be a sign that the oil pump is worn, or its suction screen is plugging up. Or you really need an oil change, badly!

By chance, are you running a much lighter-weight oil? Or much heavier?

 

[LeoGeo]

Thanks for the reply!

The oil I pulled out was in pretty bad shape, previous owner seemed to let a lot of maintenance slide for the past few years. Although I watched it come out until the final drops started, and it was a homogeneous black, no metal or water seen. Running 5w30 right now, and likely through the winter. I was going to see how much it leaked/burned and then go from there, Austin is warm enough to run 10w30 year round if needed.

I was wondering if a genuine Toyota filter would help. Are the $5 Thailand built filters readily available online of quality construction? (90915-YZZF2)

 

[LugNut]

Get one from your local Toyota dealer, just to make sure it is OEM.

I know Austin well! Hook 'em, Horns. And that green sauce at (the then-only) Chuy's was great!

 

[SlimJim16v]

Yep, try a genuine Toyota oil filter. Mahle are well regarded, but harder to find. I had a similar problem with Amsoil filters.
Where you are, you could also run a thicker oil, 10W40

 

[LeoGeo]

So while hunting for good prices on filters, I noticed something: All 4 of these filters are for use on the 97 Rav4, can you spot the one that appears to be contributing to oil starvation start up issues?

Looks to me like Bosch just undersized the inlet holes. They are even smaller than the ones on the filter designed for my 1.0L Metro! (Pictured below)

10:1 if I slap even that Wix filter on there, it'll pressurize much faster. I was wondering why the oil filter was so small when I first got the car. I guess Toyota wanted the filter to drain so it didn't dribble oil everywhere every 6 months when it was changed. Design the head with enough of an oil reservoir to withstand a second or two of no lubrication pressure at startup, fit a tiny filter that fills quickly, and a powerful pump that is able to fill it. Genius! Looks like I'll be hitting up the dealership tomorrow.

I live near the Chuy's on North Lamar, gotta love that green sauce!

 

[SlimJim16v]

You can't tell from the outside, you need to cut them open. It's do do with the valve in the filter that stops the oil draining out.

 

[LeoGeo]

I was under the impression the anti-drainback valve stops dirty unfiltered oil from draining backwards through the inlet holes into the sump, and filtered oil is normally unrestricted out of the threaded core? The ADV is what I thought had failed on the cheapo filter the previous owner installed, but I've never seen a Bosch ADV fail, and I'm quite confident the silicone it's made of is holding up. I'll be sure to check it when I pull the Bosch filter off; the easiest way is to drive a nail into the valve and see if additional oil drains out after you drain the core, no need to get super messy cutting them open! If there is a special Toyota oil filter available that has an outlet check valve in addition to the ADV, that would solve my problem for sure, but I have been unable to locate one.

How much oil normally drains from the core of the filter when you guys change them?

 

[LugNut]

Usually pretty full, no matter which of my vehicles. And a variety of filters, from OEMs to low-cost FRAMs.