New bypass system - How slow is too slow?

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Hey guys..

Just finished up my first bypass system using an LF777 filter/head. On the outlet side of the filter, I added an .035 orifice as the built-in .100 was too big.

Testing flow... oil wasn't quite at full temp, I was getting 1/2qt in 3 minutes. Just a slow constant trickle out of the return hose.

I know that slow is good... but when is it TOO slow? This is now a 14qt system meaning at that rate, it would take over an hour to flow the entire sump through the filter.

I'm thinking this is too slow to be effective.

Thoughts?
 
Hard to give any kind of advice with lack of information.

If my math is right:
your orifice change was to aprox 1/9th the cross sectional area of the org. orifice of .1"

So yes probably too drastic a change.
 
What information do you need?

The engine is a 7.3 IDIT. Oil capacity with this filter is ~14qts.

Oil pressure running down the road is ~40psi... 18-20psi at idle.

Oil being used - Delo 5w40 synthetic

I never attempted to run it without a restriction as the filter is designed for a much larger engine. Also from what I was reading, most bypass systems such as amsoil use .030" orifices.

Based on what I was reading, this orifice should flow .177gpm @40psi of water. Petroleum based oils have a multiplier of 1.07-1.27 which should come out to roughly 3/4qt per minute unless my math is off.

I'm currently no where near that.
 
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I would not run less than 0.050" orifice with only 40 PSI. Flow is pipe size and pressure dependent. 40 PSI is fine for the engine, but is not moving much oil through 0.035" ...

0.062 is only 1/16th inch. That is not much of a flow orifice.

I drill 0.035" holes in the end plugs of the lifter galleries just to lube a roller timing chain
laugh.gif
 
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I've always use 1/16th of an inch or 0.0625 for stationary engines, pumps and over the road vehicles. I think that's 1.5mm but I'm not sure and I don't have a calculator here.
 
I don't know how fast oil is supposed to flow through a by-pass filter, but why isn't running all of the oil through a by-pass filter in about an hour a huge improvement?

My understanding is that oil coming out of a by-pass filter is unusually clean, similar to fresh oil (though without fresh additives of course).
 
Originally Posted By: ecotourist
I don't know how fast oil is supposed to flow through a by-pass filter, but why isn't running all of the oil through a by-pass filter in about an hour a huge improvement?

My understanding is that oil coming out of a by-pass filter is unusually clean, similar to fresh oil (though without fresh additives of course).


That's why I'm asking if it's an issue or not. I don't know the ideal flow rate.

I wanted to know when slow is too slow... or when would flow be too slow to be effective.

As far as flow... the orifice I chose was rated - water @ 40psi. Using the multiplier, it should give the same flow rate for oil @ 40psi.. unless I'm thinking wrong?
 
On average, how long does it take you to complete 60 minutes worth of driving?

Is it a few days of driving, or a month? I think that might be of consequence in regards to flow rate.
 
I'm a believer in the orifice should equal the flow rate through your filter media (new), providing it does not drop the oil pressure to the engine by more than a pound or two...

As the media becomes contaminated, it will slow the flow. But fresh media can attain full flow, or close to it
smile.gif


Another way to look at this, is how fast do you want the by-pass to process the volume of your sump. It would be nice if the filter could handle the sump volume in 4 hours or so. Including going back and mixing with existing sump oil, it will take ten to twenty passes to get the oil fairly clean. So that would mean 40 hours filter time to get decently clean oil. All gravy after that
smile.gif
 
Think long term filtration and don't worry about slow oil flow rate (unless the slow flow is caused by the filter having reached it upper limit of dirt holding capacity). You are getting 1/2 quart every 3 minutes / one gallon every 24 minutes and there is no way to tell exactly how long ALL 14 quarts of oil in your sump will be run through the bypass filter since oil is being diverted to the bypass and at the same time it is going through a FF filter and circulating through the oil passages. Run it as is and rest assured that your oil is continually being filtered to low micron levels. Give the system you have installed time to work!!!

Nuff said,

xtell
 
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Thanks for the input guys.

As far as running at the rating of the filter... I believe it's over 2 gallons per minute which would kill oil pressure fairly quickly. Lol

I'll run it and call it good.

Thanks again!
 
AAAaaaannnddd... just because I'm a picture [censored]...





Return setup on my IDI...






Tight fit on the massive filter... Its mounted high on the battery tray and is only 2" off the top of the frame rail.

Was gonna put it under the truck.. but we are progressively building the truck into a part-time overland rig. Don't want anything vulnerable hanging that low under the truck.

Anyways..
 
Hmm... that's a new one. I've been using photobucket for years to hose pictures on forums and this is the first time I've received that error...

Looks like it's time to relocate my pictures.
 
OUCH! Apparently photobucket now charges $400 per year to use their site to host pictures to forums, etc..

Yup.. done with them. Apparently it's a new change.
 
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