Ok, so I've been at my car for way too long but what's a working man supposed to do,

I've met a few of ya, bought things, etc. Appreciate every bit of the support and thank you.

So here is the situation, mechanically my car is done.
Suspension, fuel, brakes, ignition, etc. It run as exactly as expected, and all systems work as designed.

So for the past 2 years now I've been doing what I can for the body work. Generally getting the exterior presentable, most of the panels I am going to put on the car aren't that bad of shape and I've been working on sanding/prepping for paint but work gets in the way.

So I found someone willing to take on the painting and where things fall awry are this. The oil filter was completely dry when I pulled it off, not a drop I understand it's horizontally mounted and gravity has it's affects but sure this isn't good for any engine with flat tappets

Your thoughts?

[This message has been edited by Stingray92 (edited 10-10-2024).]

I do not have any experience with the 2.5 4...But one day I went by my friend's house and he was doing an oil change on his AMC Javelin 401 (500 hp @ 7000 (He built it like a trans am race engine)....He reached down from above and un-screwed the >>HORIZONTAL<< oil filter without a pan underneath...and it did not drip one drop of oil!

Apparently, mounting the oil filter in a horizontal position allows them to drain down.

quote Originally posted by Stingray92: The oil filter was completely dry when I pulled it off, not a drop...

The obvious question, other than what engine do you have... is whether the engine had been run after the oil filter had been installed?

I can't see how an oil filter on a Fiero 2.5 or 2.8 could be empty if there ever was oil in it.

Sorry for not providing the info earlier yes its an 84 2.5. The engine has been run and verified to have good oil pressure prior to start and during operation. That said I have let it sit while tending to the exterior. The filter I put on was an AC delco. I'll prime it again with an external pump/filter and go from there. This just seems odd, but thanks in advance.

quote Originally posted by Stingray92: The oil filter was completely dry when I pulled it off, not a drop...

I just don't see how that is possible. Look at the angle of the oil filter on the duke below. How would the oil run uphill to completely drain the filter?

quote Originally posted by 82-T/A [At Work]:

quote Originally posted by Stingray92: I'll prime it again with an external pump/filter and go from there.

Maybe what you should do is remove the fuel pump fuse, crank the engine over a bit, and then remove the oil filter to see if it now has any oil in it.

[This message has been edited by Patrick (edited 10-11-2024).]

Ok just so everyone knows where this stands,

This motor was a doner, I got years ago. It has good compression and oil pressure is at 50 on an auxiliary pump with ambient about 65 today.

While I had it out of the engine bay I did most probably anything many of us do, it's obviously easier when out right?

So tonight I drained the oil and it had only been run for less than 20 hours and I'm less than pleased. The drain plug had quite a bit of build up on it and the oil is dark as coffee.

As far as my prep for restart I am using an oil circulation pump with a filter before I attempt to even turn it over. As far as the fuel pump goes I'll just pull the connector of the injector and check for fuel leaks at the same time.

[This message has been edited by Stingray92 (edited 10-12-2024).]

quote Originally posted by Stingray92: So tonight I drained the oil and it had only been run for less than 20 hours and I'm less than pleased. The drain plug had quite a bit of build up on it and the oil is dark as coffee.

So the engine ran for a few hours, and the oil was dark... and not a drop of oil was in the filter. I dunno, sure seems strange to me.

Is it possible for there to be some issue with the oil bypass valve and oil was simply being diverted away from the oil filter? That might also help to explain why oil which only had a few hours on it was so dark... as none of the impurities in the crankcase were being filtered out.

[This message has been edited by Patrick (edited 10-12-2024).]

Sounds like it's missing the oil bypass valve... so it's completely skipping the oil filter altogether.

EDIT: FYI, you can get to it by removing the oil filter.


Now I'm wondering if my daughter and I remembered to check to see if there was one already in there when we got it back from the machine shop... ugh...

[This message has been edited by 82-T/A [At Work] (edited 10-12-2024).]

Hey guys, thanks for the replies. So after flushing for 12 hours still not as clean as I'd hope. I'm going to flush it some more before trying to even crank it. The filter did have dirty colored oil in it and maybe just from sitting it drained through, at any rate I'll see what I can do to check the bypass valve, something I don't recall doing before putting it back in the car doh!

It'll be a few days but I'll let you know how it turns out.

quote Originally posted by Stingray92: at any rate I'll see what I can do to check the bypass valve

I don't even know if it's possible, but make sure it's not stuck in the open position.

Ok, so I was able to look at it late this afternoon and the oil supply is clocked at about 8 which is lower than the filtered supply directly in the middle. The bypass is on top and is moving/seating as expected. There is some resistance but not sure the exact pressure.

Anyway here is the pic of the oil filter housing



And just for teasers

[This message has been edited by Stingray92 (edited 10-13-2024).]

Hi Stingray . nobody has mentioned oil filters themselves. Some filters have check valves in them and others do not. I would double check that you have the appropriate filter for your duke. the ones that usually don't have a check valve are mounted vertically and can't drain back. Hope this helps you. sleek

Sleek thanks, I'm sure others were thinking the same thing. So I cut 2 filters open, the one empty and the one I used for flushing. The Delco filter diaphragm was week at best, the other brand was much more pliable albeit newer (purchased).

After I flushed the engine a few days ago and let it sit the fresher filter had oil retained in it.

In case anyone is curious here's a photo of the cut open filters.



Are 8 ports better than 6?

FYI the media on the suspect filter looked like garbage, the flush filter more expected.

[This message has been edited by Stingray92 (edited 10-16-2024).]

quote Originally posted by Stingray92: Are 8 ports better than 6?

The six port filter has larger ports. I would think the same amount of oil would circulate through the filter. If not I would think you oil pressure readings would be higher.