Deteriorating filters+ Oil By Pass Valve

[Patman]

quote:

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Originally posted by Chris:
Hey.. Hey..who took over my thread and changed my title??!! Oh I guess it was the owner of the site...Bob... thats alright then. But don't ever do this again or I'll...well I'll just watch it morph again and sulk.

Anyway, is my thinking correct that 1 year is too long for the paper element and 6 months may be max. irregardless of miles?

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That sounds about right. A lower quality filter media just can't handle a one year interval like a blended or fully synthetic media would. That's what makes the Supertech a good bargain too, a $2 filter that has a blended media.

Hey Bob, if you don't want to try out the K&N, why not try out a Bosch Premium or a Supertech?! Either of these will be better than the Fram too.

 

[BOBISTHEOILGUY]

quote:

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Originally posted by XHVI:
Bob, I think what you're seeing with the "still wet" M1 media is the M1 media's ability to retain oil (like an efficient sponge) versus the Fram's inability to do so. The extra oil that was in the M1 can is a result of the M1 media's ability to hold the oil (again, like an efficient sponge) rather than its simply preventing the oil from draining out. JMHO

And I still can't believe you'd use a Fram POS filter.

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I agree, it's like a sponge, but because it is acting as such, it also is restricting the flow through the media thus providing more pressure difference. This is exactly what you don't want, you want a filter that will allow more oil to flow through the media not the by pass valve.

I'm not all that excited with the fram but... Looking at the wear numbers, and basic structure of this filter, simple as it is, it isn't proving to really be all as bad as one would be lead to believe. There was no deterioration of the cardboard ends and this one has a rubber anti drain back valve like the m1 and puralator. Now, I have taken one apart that didn't have a by pass valve built in to the filter and it too didn't have any kind of anti drain-back valve other than the cardboard end. So, I guess it depends on the design you are using.

The issue I have is flow. Interesting how many people are so worried about flow to such a point that they use 0w oils so it can flow easier, but then put in a high efficient filter which tends to resist flow more, thus causing more "dry" starts than if they were to put in a less resistive oil filter.

I'd like to see someone that does constant oil analysis, that has an established trend with a certain filter, try a cheap fram filter just to see if their wear numbers don't drop slightly.

I think this is another case where technical data sheets mis lead actual field testing as it looks great on a bench for filtering out sub micronic particles but fails to take into account startup flow with cold oil, and flow rates through the media and such. All of these variables would change from one person to another since each use different oil pumps which produce different pressures and different viscosity oils, different brands, and many other aspects not able to be accounted for in plain bench testing.

 

[G-MAN]

quote:

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Originally posted by BOBISTHEOILGUY:
I agree, it's like a sponge, but because it is acting as such, it also is restricting the flow through the media thus providing more pressure difference. This is exactly what you don't want, you want a filter that will allow more oil to flow through the media not the by pass valve.

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I'm not sure your premise is sound. Just because the media will hold more oil, it doesn't follow that it will be more restrictive.

 

[BOBISTHEOILGUY]

Patman, After going back out to the shop, I cut a bosch filter open. that one I may try next as it looks like it isn't that restrictive. I took some pics of all the filters I have cut open. The two on the left are used and off a lexus. Even though used, figured you could get a good idea on how compressed the media is.

From where I see it, the more compressed a media is, the more restrictive to flow. That plus the type of media used to filter makes a difference. Just from pure mechanical looks, there is less pleats for the fram and bosch than the others.

[ January 04, 2003, 08:39 PM: Message edited by: BOBISTHEOILGUY ]

 

[BOBISTHEOILGUY]

quote:

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Originally posted by XHVI:

quote:

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Originally posted by BOBISTHEOILGUY:
I agree, it's like a sponge, but because it is acting as such, it also is restricting the flow through the media thus providing more pressure difference. This is exactly what you don't want, you want a filter that will allow more oil to flow through the media not the by pass valve.

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I'm not sure your premise is sound. Just because the media will hold more oil, it doesn't follow that it will be more restrictive.

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Well, you got me to thinking so here's what I tried, I took a dish rag, and covered the nozzel of the sink while it was running water at a slow moderate rate.. water flowed through it no problem and very little resistance. Now I doubled the fold, again covered the nozzel, and water was trying to come out the sides, of course when I layered the rag again, there was no way the same water flow could penetrate through all of this "media" and was spewing all over. I think I stand by my original statement, higher restriction, lower flow.

Chris I'm the guilty one! ya caught me. Please don't beat me up to bad..

really wasn't trying to change it but felt the topic was broadened and wanted others to see more on this subject as I think many really don't quite understand how a by pass valve works on full flow filters and thought I'd take the time to open this up a little. Thanks for taking it easy on me!

Your a good man.

[ January 04, 2003, 08:37 PM: Message edited by: BOBISTHEOILGUY ]

 

[TheLoneRanger]

Bob, it seems to me the flow will be greater in the filters with the MOST pleats (Motorcraft, Purolator, Mobil 1) Everything else being equal, the more pleats, the more surface area, and the less resistance to flow. The distance between the pleats dosen't matter, as long as they aren't touching.

It is getting late, and my brain cell is hurting, so if this is off-base, forgive me.....

 

[BOBISTHEOILGUY]

quote:

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Originally posted by TheLoneRanger:
Bob, it seems to me the flow will be greater in the filters with the MOST pleats (Motorcraft, Purolator, Mobil 1) Everything else being equal, the more pleats, the more surface area, and the less resistance to flow. The distance between the pleats dosen't matter, as long as they aren't touching.

It is getting late, and my brain cell is hurting, so if this is off-base, forgive me.....

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That's a good point but look at the m1 filter and the bosch, both appear to be about the same size but the m1's pleats are tighter so they are compressed, kind of like taking that dish towel and folding it from a single layer to a double layer. The bosch on the other hand appears to be spead out for the same area and allowing for more flow through the wider gaps.

 

[Spector]

So, if the filter is in bypass a good portion of the time what is to prevent the particles that are captured in the media from simply being washed out again and being circulated. As such, if they do get re-circulated the actual ability of filters to prevent wear is about nil. The oil is doing all the work.

I have left my Amsoil filter on a year and media seemed okay, in fact the Fram I jsut changed out at 1 1/2 years, althought the media was mis shapen it did not in any way crumble. Although 1 1/2 years it did have only 4000 miles on it.

So, we seem to be leaning towards cheap higher flow filters and based upon what I have seen doing autopsys on them I agree. And, if in bypass much of the time as Bob says, perhaps with new oils, better engines they are USELESS APPENDAGES!

 

[MavRick]

Bob, I think you interesting points but there is one major assumption that needs to be proven. That is how much pressure drop is there on a filter under certain steady state conditions. For instance cruising at 65 mph what is the pressure drop on the filter, and is it in bypass mode. My guess is it isn't in bypass in most steady state conditions of driving. If accelerating, then it is likely to kick in the bypass valve. While idling with the engine warm it's unlikely to be in bypass IMO.

If it is true that the filter commonly is dropping 8-12psi or more, then your hypothesis could explain lower wear numbers for the Fram Vs the Mobil 1. On the other hand, what the lower wear numbers could mean is higher flow is more important than high filtering. So in that case K&N wins that battle over either Fram or Mobil 1.

I use a K&N Golf for my external transmission filter and have no problems with flow. I called B&M that makes these and they estimate a differential pressure of 4psi for the external transmission filter which is a Fram PH8A. Of course the viscosity of ATF is lower than Motor Oil.

If you want to get a K&N to test go online at summitracing.com. Do a keyword search for "Oil Filter Gold"

[ January 05, 2003, 12:44 AM: Message edited by: Giles ]

 

[BOBISTHEOILGUY]

quote:

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Originally posted by Spector:
So, if the filter is in bypass a good portion of the time what is to prevent the particles that are captured in the media from simply being washed out again and being circulated. As such, if they do get re-circulated the actual ability of filters to prevent wear is about nil. The oil is doing all the work.

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The design of the media would keep any particles from dropping out. The V shape design is designed to capture what is flowing, bringing it to a point where it would get trapped in the smallest part of the V not allowing it to fall back into the oil. This would work provided it does get into the filtered oil and as long as the oil is flowing through the filter.

Giles
Obviously there is no scientific data to support what I am saying except lab reports on wear numbers and that what I am proposing here is my theory as to what is happening based on my mechanical/lubrication background.

Looking at the info I have provided, wear analysis, pics of filters and such, This filtering was something that was rearing its ugly head and made me wonder about some issues when I had a m1 filter, drained for 2 months, cut it open and it was still full of oil!. This made me wonder why was it still full of oil, only the media was in place to keep it flowing out so why wouldn't it drain under gravity? My first thoughts were, well, it's obvious that at 10,500 miles on this one filter, I have long passed by it's useful life and it's plugged up, so then I decided to do it at 4,000 miles and the same exact senerio happened. It too, would not drain after a 2 month drain period. OH, now I see there is higher resistance to flow under gravity. So it now became obvious it requires oil pressure to push the oil through this media. So, to prove a point about how additives is what protects engines from wear and there is little difference if any between which type of base oil you use, I switched to the fram filter and our mineral based oil, which had no synth base in it as opposed to our blend. Now all of a sudden, my wear numbers decreased using the mineral oil with the same basic additive package as the blend. Now, this really had me interested as to what is happening here.

So,looking at this, I took a brand new fram and m1 filter, put fresh new oil in a can, and dipped the new m1 filter and fram filter into the can and watched for how long the oil took to travel through the media. Interesting enough both took approx the same amount of time, so from what I'm seeing, the filtering process is identical as both had to absorb the oil into the media and slowly passed the oil through. So, this now leads me to the next issue, after 4k of driving with an m1 filter, it wouldn't gravity drain, whereas after 4k and 7k of use on a fram, both would completely drain under gravity. What gives? question that I have is, is it that the m1 filter has filtered out more particles than the fram, therefore now has collected more and clogged it from gravity draining?
What does this mean. Well, from what I have figured out, I'd rather have better flow as this is also proving that start up wear is a lot more agressive than one really would have expected and that issue to me is now more a fact.

 

[TheLoneRanger]

Bob, you have turned the oil industry upside down!

I am now going to stock up on Frams and use whatever mineral oil Wal-Mart has on sale.

Just kidding. But you have brought up a good point. BTW, in years past I did use Frams and mineral oil exclusively. My engines remained clean inside, and never experienced a major failure, with several going over 150K miles.

 

[Tommy]

Bob,

It seems that you are overlooking some very basic hydraulic principles:

quote:

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Oil pump produces anywhere from 30-60LBS of oil pressure

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The oil pump produces flow not pressure - it is the resistance to flow that produces pressure. I am not nit-picking, this is an important point.

quote:

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Lets say 40lbs of pressure is now on pushing inward on the filter media to go through and be filtered. Can a filter media allow 40lbs of oil pressure to pass through it at once?

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The 40 PSI pressure here is caused by the restriction to flow at the engine bearings etc., not from the restriction of the filter element. If you have 40 PSI acting on the outside of the filter element, you also have about 40 PSI on the inside of the element. The filter media does not allow pressure to pass through it as you say, it passes flow.

quote:

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So, if you have 40lbs of pressure on one side of the media(outer in this case) and with the media allowing say 20lbs through at a time(no real idea as to what it is but no way 40) you now have a difference of 20lbs between the inside of the media and the outside. Bingo, you've exceeded the 8-12lb limit thus it has opened.

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There is no way that any filter manufacturer would design an element with a 20 PSI pressure drop! I would say that the pressure drop is closer to 1 or 2 PSI, and this is a far from the 8-12 lb. value of the bypass valve. Flow rates are actually very low in an engine lubricating system - if you look at specs. on hydraulic filters for example, you will be amazed at how low the pressure drops are with much higher flow rates and with tighter media!

Remember, pressure drop across the filter media is determined by the following factors:

1) Flow rate (GPM of lube system)
2) Area and "tightness" of the media
3) Viscosity of the oil

So, just because a filter is more efficient, it does not necessarily mean that it restricts more - is it not possible that they have included more media area?

 

[BOBISTHEOILGUY]

Tommy, I have a question for you but before I ask it, let's both get on the same page with the definition of flow and pressure.

--------------------------------------------
flow ( P ) Pronunciation Key (fl)
v. flowed, flow·ing, flows
v. intr.

To move or run smoothly with unbroken continuity, as in the manner characteristic of a fluid.
To issue in a stream; pour forth: Sap flowed from the gash in the tree.
To circulate, as the blood in the body.
------------------------------------------
pres·sure ( P ) Pronunciation Key (prshr)
n.

The act of pressing.
The condition of being pressed.
The application of continuous force by one body on another that it is touching; compression.
Abbr. P Physics. Force applied uniformly over a surface, measured as force per unit of area.
----------------------------------------

Now, using these definitions of pressure and flow
let me ask this Generated from your comment of mine..
quote:
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Lets say 40lbs of pressure is now on pushing inward on the filter media to go through and be filtered. Can a filter media allow 40lbs of oil pressure to pass through it at once?
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(your response to this is, and bear in mind those numbers are/were hypothetical)
The 40 PSI pressure here is caused by the restriction to flow at the engine bearings etc., not from the restriction of the filter element. If you have 40 PSI acting on the outside of the filter element, you also have about 40 PSI on the inside of the element. The filter media does not allow pressure to pass through it as you say, it passes flow.


If what causes pressure is from the bearings and such(Which I agree with and stated as such in my original post), Then if a filter media has flow resistance(or flow restrictions) would this not create pressure on the outside of the filter media? Ever seen a hydraulic filter collapesed? Isn't that where flow was restricted to such a point that the pressure was greater than the media could handle? Doesn't that have pressure at that point? At any place in a closed in lube system, pressure can be created, before and after the filter. You could even have a higher pressure reading before the filter and a lower filter reading after the filter because the resistance to flow at the filter could be greater than the resistance of flow at the bearings. Is that not possible? Obviously, the idea is to have equal and even pressure in a lube system which would mean even flow throughout the system.

you will be amazed at how low the pressure drops are with much higher flow rates and with tighter media! I guess this is a second question, sorry, but isn't hydraulic fluids usually thinner than motor oil(iso 32-high end of 10wt, iso68 =20wt?) And the size of the hydraulic filter system, are they as small as motor oil filters? I would think that the hydraulic filters are many times bigger due to the higher filtration requriements required and that would allow more fluid to pass or flow through thus creating less back pressure. I honestly haven't delved into hydraulic systems that much so I'm sure I may be off, but if need be, I'll research more on the subject of hyd filtration systems.

 

[Patman]

In this one picture that Bob posted, doesn't it look like the filter is floating in mid air? It's a magic filter!

 

[Tommy]

Yes Bob, filters can and do collapse - but only when clogged. What we are talking about here is filters in normal operation. I maintain that in normal operation, pressure drop over the filter media is minimal, and not anywhere near the hypothetical 20 PSI that you are talking about.

I know of a hyd. filter that we use (Fleetguard) that is rated for around 70 GPM - it is 10 micron with an efficiency in the 90's - it is not much bigger (if any bigger at all) than a Ford Powerstroke filter. The bypass is set for around 25 PSI for this filter. (Fleetguard filter head also) A flow rate of 70 GPM is many times higher than you are going to find in any engine's lube system. If I have time next week I will get all the data from Fleetguard and post it.

I still also maintain that it is not correct to assume that because a filter has a higher efficiency, it will restrict more flow. Filter efficiency is only one variable - the media area mut also be taken into consideration.

There is also the argument that a tighter media does not necessarily mean that it is more flow restrictive. I have heard the analogy that a cellulose media (viewed under a microscope) looks like a bunch of flat strips criss-crossed and overlapped. A synthetic media then looks like a bunch of round straws criss-crossed and overlapped. Using the synthetic media allows for a tighter weave without an increase in the restriction to flow.

 

[rugerman1]

Patman,Bob just threw it up in the air and sapped the picture on its way down!REMEMBER this is BOB were talking about!

Mark

 

[BOBISTHEOILGUY]

quote:

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Originally posted by Tommy:
Yes Bob, filters can and do collapse - but only when clogged. What we are talking about here is filters in normal operation. I maintain that in normal operation, pressure drop over the filter media is minimal, and not anywhere near the hypothetical 20 PSI that you are talking about. I agree, and should have been more realistic as it can't with a 8-12lb bypass valve, it will go into bypass as soon as the oil hits the media and pypass. Once the pressure equals out, no matter what pressure it is, then the bypass will start to close back until the pressure difference increases back to the 8-12 lbs then it would re open. This in my opinion happens more than one would imagine, particularly with higher filtration media.

I know of a hyd. filter that we use (Fleetguard) that is rated for around 70 GPM - it is 10 micron with an efficiency in the 90's - it is not much bigger (if any bigger at all) than a Ford Powerstroke filter. The bypass is set for around 25 PSI for this filter. (Fleetguard filter head also) A flow rate of 70 GPM is many times higher than you are going to find in any engine's lube system. If I have time next week I will get all the data from Fleetguard and post it. While you're looking up this info, see if you can find out the difference in how much test pressure is used to push the 70gpm in a hyd system for rating a filter(btw, this is a full flow hyd filtler you're talking about?) vers the test pressure used to establish gpm for an automotive full flow filter.

I still also maintain that it is not correct to assume that because a filter has a higher efficiency, it will restrict more flow. Filter efficiency is only one variable - the media area mut also be taken into consideration. I totally agree, size, filtration media, pressure produced by pump, oil viscosity etc...

There is also the argument that a tighter media does not necessarily mean that it is more flow restrictive. I have heard the analogy that a cellulose media (viewed under a microscope) looks like a bunch of flat strips criss-crossed and overlapped. A synthetic media then looks like a bunch of round straws criss-crossed and overlapped. Using the synthetic media allows for a tighter weave without an increase in the restriction to flow. I haven't proved or disproved that and have no conclusions on that part of the subject.

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[Tommy]

quote:

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While you're looking up this info, see if you can find out the difference in how much test pressure is used to push the 70gpm in a hyd system for rating a filter(btw, this is a full flow hyd filtler you're talking about?) vers the test pressure used to establish gpm for an automotive full flow filter.

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Well here we go again............if a filter manufacturer tells me that their filter is rated for 70 GPM with x pressure drop across the media then that is the pressure that it took to push the 70 GPM through the media. If the test was conducted at 1000 PSI or 10 PSI, it makes no difference - what matters is the pressure differential across the media.

For example - let's say the filter has a 2 PSI differential @ 70 GPM.....if we are flowing 70 GPM @ 1000 PSI, we will then have 998 PSI on the other side of the media. If we are flowing 70 GPM @ 10 PSI, we will then have 8 PSI on the other side of the media.

Of course, one pressure spec. that they will give is the maximum allowable working pressure for the filter unit.

[ January 06, 2003, 12:23 AM: Message edited by: Tommy ]

 

[Ken2]

I received the following info from Travis Winberg, service engineering supervisor for Baldwin Filters about their B2 (Ford 302 & 351 V8 engine filter which I use):
--quote--
The B2 and B2-HPG will flow approximately 4 gpm at a pressure differential of 7.5 psi. these filters contain an 8 psi by-pass valve. Therefore, the filters will by-pass when the differential pressure across the filter becomes 8 psi or greater.

The B2 is 22 micron nominal ( Beta @ 2 = 2) and 45 absolute (Beta @ 45 = 75). the B2-HPG is 8 micron nominal and 23 micron absolute.
--end quote--

My questions to Mr. Winberg:
Regarding your B2 and B2-HPG, can you provide the following info:

1) Flow rate with warm engine oil.
2) Pressure drop through the clean filter with warm engine oil at this flow
rate.
3) What degree of clogging of the filter will cause the warm oil to bypass
in normal operation, including high rpm operation.
4) Beta ratios for these filters.

So...what's the output of most standard oil pumps? 4gpm or less? With lower capacity oil pumps or slower engine speeds the clean/warm differential pressure will be less than 7.5 psid. The filter will not be in bypass with warm oil until the filter begins to clog. Even when the filter does start to bypass, the bypass valve modulates and only opens enough to dump excess flow. There is still 8 psi pushing any oil that'll go though the filter media. Note also that many engines are spec'ed with filters requiring bypass settings higher than 8...I have two with 17-18 psid bypass settings, although many aftermarket filters are sold with the 8 psid bypass, seemingly to reduce inventory requirements.

Does anyone have a contact at Champion Labs to get similar info for their Mobil1 M1-301 (for these Fords) and the Mobil1 M1-209 (which I think fits the 1.9L Ford Escort engine)?

Ken

[ January 06, 2003, 02:48 PM: Message edited by: Ken2 ]

 

[jsharp]

quote:

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Originally posted by Tommy:

quote:

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While you're looking up this info, see if you can find out the difference in how much test pressure is used to push the 70gpm in a hyd system for rating a filter(btw, this is a full flow hyd filtler you're talking about?) vers the test pressure used to establish gpm for an automotive full flow filter.

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Well here we go again............if a filter manufacturer tells me that their filter is rated for 70 GPM with x pressure drop across the media then that is the pressure that it took to push the 70 GPM through the media. If the test was conducted at 1000 PSI or 10 PSI, it makes no difference - what matters is the pressure differential across the media.

For example - let's say the filter has a 2 PSI differential @ 70 GPM.....if we are flowing 70 GPM @ 1000 PSI, we will then have 998 PSI on the other side of the media. If we are flowing 70 GPM @ 10 PSI, we will then have 8 PSI on the other side of the media.

Of course, one pressure spec. that they will give is the maximum allowable working pressure for the filter unit.

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To repeat - " If the test was conducted at 1000 PSI or 10 PSI, it makes no difference - what matters is the pressure differential across the media."

This is what matters. Differential pressure. This is function of the viscosity of the oil, how restrictive the filter is, how restrictive the system is downstream from the filter, and the system flow rate.

Honestly, I can't believe that once the pressure comes up in the oiling system that the filter is ever in bypass. I can see it during cold starts but once the system is up to pressure past the filter the differential pressure across the filter should drop below the bypass value IMHO.

Provided you have a large enough filter for your anticipated flow rate of course...

I surprised no one here has put a differential gauge on a remote adapter yet to see conclusively if filter bypass ever occurs...

[ January 06, 2003, 12:27 PM: Message edited by: jsharp ]