Oil Pressure question

[Ecomike]

Considering the cost of an engine I am probably going to stick with K&N or Mobil one from now on, but I have bought one of each and I am getting ready to run a pressure test comparison between them and the Quaker State (Really its a Fram in disguise) that I was forced to buy recently at the oil change place I used (I use to use that is).

I have read that the oil pressure is measured after the filter and I am starting to think some of the oil pressure problems and engine bearing damage and wear is being caused by plugged up filters, and / or leaking filters (antidrain back valves opening and leaking back to crankcase while the engine is running reducing the flow and pressure to the bearings and the presure gauge) in addition to all the other problems others have posted about the cardboard end caps.

I am also preparing to upgrade my oil filter adapter to allow me to use the larger oil filters.

 

[clunk]

changed out the FRAM filter for an equally cheap (motormaster) oil filter this morning and I'm happy to say that my oil pressure has increased a fair bit. It wasn't dangerously low before, but it still registered lower than I was comfortable with.
For some reason I can't seem to get a decent oil filter here! I have tried and tried, but everywhere just stocks FRAM. Decided to spend the 4 dollars on a new motormaster filter and it did the trick. I think the anti-drain back wasn't working properly.

 

[Ecomike]

changed out the FRAM filter for an equally cheap (motormaster) oil filter this morning and I'm happy to say that my oil pressure has increased a fair bit. It wasn't dangerously low before, but it still registered lower than I was comfortable with.
For some reason I can't seem to get a decent oil filter here! I have tried and tried, but everywhere just stocks FRAM. Decided to spend the 4 dollars on a new motormaster filter and it did the trick. I think the anti-drain back wasn't working properly.

Great news. :sunshine: The only question now is whether the filter was plugging up with sludge earlier than normal (whatever that is) and thus lowering the oil pressure to the engine and the sensor, or if the antidrainback valve was leaking, or maybe some of both!

Thanks for the report on your success!!! Perhaps it will encourage others to try some similar filter only swaps to see how common this is!:yap:

 

[Ecomike]

changed out the FRAM filter for an equally cheap (motormaster) oil filter this morning and I'm happy to say that my oil pressure has increased a fair bit. It wasn't dangerously low before, but it still registered lower than I was comfortable with.
For some reason I can't seem to get a decent oil filter here! I have tried and tried, but everywhere just stocks FRAM. Decided to spend the 4 dollars on a new motormaster filter and it did the trick. I think the anti-drain back wasn't working properly.

Clunk,

When you get a chance can you please quantify the new pressures with the new filter???? Many would like to know how much difference it made.:sunshine:

 

[clunk]

Clunk,

When you get a chance can you please quantify the new pressures with the new filter???? Many would like to know how much difference it made.:sunshine:

It's hard to compare because I'm in canada and my XJ is measured in bars, not PSI. All I can do is estimate, but at times today when I was out for a drive my oil pressure was dropping as low as aroudn 15PSI at hot idle, which was a first. I have always had the equivalent of around 23PSI+ at hot idle as a minimum.
It is definately a difference, and I feared that with the FRAM filter it would continue dropping until it reached below 13PSI (causing me to have an aneurism and shit a brick).
It's interesting to note that the FRAM had good pressure initially, yet after around 200km's of driving it had started to wane noticably, REALLY noticably. The motormaster looks like it might even be a rebadged FRAM filter, but it is giving me good pressure again. I'll see how long it lasts. To be safe I will be replacing it with something like a delco or K&N unit as soon as I have the chance..I have not been able to find one to date here, only fram, quacker state and motormaster(checked all local parts stores). Also some brand named "viper" which looked really cheap. Didn't want to risk it.

THIS IS THE INTERESTING/IMPORTANT PART:

It's also very interesting to note that when I removed the FRAM filter, there was less than 1/8th of a quart of oil in it. Normally, if the anti-drainback valve in there was working right it should hold close to a quart. I think the valve was buggered and was letting all oil drain back into the block and not holding any in the oil filter explaining why it was so empty when I removed it. That would lead to dry starts and a low or nonexistant PSI reading initially, which I believe I was experiencing.
Long story short, I'm done with fram. When I have the chance I'll be swapping to something like a K&N oil filter which I trust. I don't really trust the motormaster since it just looks like a rebadged FRAM and the internals(holes etc) all looked the same as

 

[Ecomike]

Clunk,

Thanks for the update. What year is your engine, is it a 1 quart, or 1/2 quart filter you are using? What is the Fram part number?

So the presure came back up at hot idle by about 8 psi? (23-15=8) If so that is a huge number for many others here to consider!:sunshine:

So is your gauge showing, calibrated in tenths of a bar?

1 bar is = to 14.5 PSI.

 

[clunk]

the engine is a 1990 4.0
I'm was using whatever the stock filter size is, FRAM P/N 3985 I believe.
I don't see much difference either way whether it was a 1/2 or 1 quart filter---there was literally nothing in the filter, and the oil that drained when I changed the filter was trapped in a clean ice cream bucket. Poured it into an old empty oil bottle and verified it was in fact even less than 1/8th of a quart. Punched a hole in the bottom of the used FRAM filter and let the remaining oil drain out, and after draining for an hour I only got another 2 tablespoons out of it. There should have been much more oil in there no matter how you look at it. When I removed the old DELCO filter before this past oil change, it had trapped nearly a quart of oil after I punched a hole and let it drain(this is an estimate, I didn't measure it, but ALOT came out compared to the fram filter).

My gauge reads 0-3-5.4 bars with one hash mark between each of those figures(representing approx. 1.5 bars I guess?)
My figures are definately not the most accurate thanks to the crappy gauge setup, but I can tell you it was drastic enough of a difference to be relieved.

 

[Ecomike]

the engine is a 1990 4.0
I'm was using whatever the stock filter size is, FRAM P/N 3985 I believe.
I don't see much difference either way whether it was a 1/2 or 1 quart filter---there was literally nothing in the filter, and the oil that drained when I changed the filter was trapped in a clean ice cream bucket. Poured it into an old empty oil bottle and verified it was in fact even less than 1/8th of a quart. Punched a hole in the bottom of the used FRAM filter and let the remaining oil drain out, and after draining for an hour I only got another 2 tablespoons out of it. There should have been much more oil in there no matter how you look at it. When I removed the old DELCO filter before this past oil change, it had trapped nearly a quart of oil after I punched a hole and let it drain(this is an estimate, I didn't measure it, but ALOT came out compared to the fram filter).

My gauge reads 0-3-5.4 bars with one hash mark between each of those figures(representing approx. 1.5 bars I guess?)
My figures are definately not the most accurate thanks to the crappy gauge setup, but I can tell you it was drastic enough of a difference to be relieved.

Thanks. The Fram #3985 filter, the Renix standard filter size is actually a 1/2 quart capacity according to some research sites I have visited on the filter topic recently. The newer jeeps use a larger 3/4" thread on the filter and are able to use (if one knows about it) a larger, non-standard 1 quart filter. I am preparing to upgrade mine to the newer 1 quart size to help with the filter pressure drop issue, so I can get more flow and pressure to my older tired 4.0 engine.

The four best sites I found on this are;

http://www.madxj.com/MADXJ/technical/technicalfiles/ARoilFilterConversion/OilFilterConversion.htm

Http://www.yuccaman.com/jeep/filter.html

http://minimopar.knizefamily.net/oilfilterstudy.html

http://www.frankhunt.com/FRANK/corvette/articles/oilfilterstudy/oilfilters.html

 

[Ecomike]

Well I think I just found another piece of the puzzle thatI have been puzzling over. Knize says the following on his filter study page and I am inclinded to think he may be right to some extent, or in some cases, depending on the oil viscosity, temperature and filter.

"Also, when the oil is cold and very thick, it will tend to bypass the filter through the pressure relief valve because it cannot pass through the element until it thins out somewhat. If it did not do this, the filter element media would tear open."

Quoted from:

http://minimopar.knizefamily.net/oilfilters.html