fl500s and fl820s interchangeable?

Status
Not open for further replies.
Sorry if this has been posted, but i didnt have much luck with the search...
 
Last edited:
I think it's one of those cases of 'if you have room', you can use the FL-820S.....some engines may have tight spaces where only the FL-500 will fit.

With the vehicle under warranty, I'd stick to what Ford calls for on the vehicle...if something goes wrong, and they find the wrong filter there, you might loose your warranty.

Mine's long out of warranty, so I can 'afford' to experiment...but if I were in your shoes, I wouldn't.
 
Originally Posted By: cobos06GT
Yeah, i guess ill just return it, no big deal. Not work using the wrong filter to save a few bucks.


You might want to ask ford - they may well allow it, I don't know!

laugh.gif
 
Originally Posted By: Roadkingnc
fl820 and fl500 will interchange I would rather have the 820 for the extra capacity and media


The FL820 has a 16 PSI bypass vs the Fl500S which has an 8 lb bypass. In other words the FL500S is in bypass more often, especially on cold starts. The FL820 is a cheap filter, is it really worth a possible increase in engine wear?
 
Originally Posted By: Joenpb
Originally Posted By: Roadkingnc
fl820 and fl500 will interchange I would rather have the 820 for the extra capacity and media


The FL820 has a 16 PSI bypass vs the Fl500S which has an 8 lb bypass. In other words the FL500S is in bypass more often, especially on cold starts. The FL820 is a cheap filter, is it really worth a possible increase in engine wear?


Not necessarily ... the bypass setting can also be dependent on how restrictive the filter media is, or even how fast the filter is anticipated to clog up with debris.

In other words, the filter with the higher bypass setting may not flow as well and create more delta P across the element, and/or might clog easier/faster because of the design of the media itself, which would increase its flow resistance quicker. Another important factor is what the expected oil flow rate is in the engine it's specified for, and the recommended oil viscosity range for that engine. Many factors go into the design.

Therefore, the engineers might have set the bypass valve setting higher to prevent unnecessary bypass openings based on these kind of design factors.
 
Originally Posted By: ZeeOSix
Originally Posted By: Joenpb
Originally Posted By: Roadkingnc
fl820 and fl500 will interchange I would rather have the 820 for the extra capacity and media


The FL820 has a 16 PSI bypass vs the Fl500S which has an 8 lb bypass. In other words the FL500S is in bypass more often, especially on cold starts. The FL820 is a cheap filter, is it really worth a possible increase in engine wear?


Not necessarily ... the bypass setting can also be dependent on how restrictive the filter media is, or even how fast the filter is anticipated to clog up with debris.

In other words, the filter with the higher bypass setting may not flow as well and create more delta P across the element, and/or might clog easier/faster because of the design of the media itself, which would increase its flow resistance quicker. Another important factor is what the expected oil flow rate is in the engine it's specified for, and the recommended oil viscosity range for that engine. Many factors go into the design.

Therefore, the engineers might have set the bypass valve setting higher to prevent unnecessary bypass openings based on these kind of design factors.


My thought is the bypass is to protect the filter element from collapsing or tearing from pressure difference and has nothing to do with the application. I do think the 500 will be in bypass more vs the 820, maybe not so much on my 1.6l engine
laugh.gif
.
 
I understand your poinr Z06, but its well known that Ford's horizontal mounting of the oil filter contributes to leakage by the anti drain back rubber or silicone. The lower bypass of the FL500S has everything to do with getting more oil to the motor on start up. Many of Ford's new models use this filter, and it looks like the FL820S is slowly being phased out.
 
Originally Posted By: Provi
My thought is the bypass is to protect the filter element from collapsing or tearing from pressure difference and has nothing to do with the application. I do think the 500 will be in bypass more vs the 820, maybe not so much on my 1.6l engine
laugh.gif
.


Sure the bypass valve setting has something to do with application. It's thinks like oil viscosity, oil flow volume, debris loading rate, media flow restrictiveness that determine what the actual PSID will be across the media under normal use conditions. The engineers then tack on some PSID headroom onto the bypass valve opening setting so it won't open unless it has to.
 
Originally Posted By: Joenpb
I understand your poinr Z06, but its well known that Ford's horizontal mounting of the oil filter contributes to leakage by the anti drain back rubber or silicone. The lower bypass of the FL500S has everything to do with getting more oil to the motor on start up. Many of Ford's new models use this filter, and it looks like the FL820S is slowly being phased out.


The mounting orientation or the material used for the ADBV should have nothing to do with the bypass valve setting. If these filters are draining back because of bad ADBVs, then Ford should fix that instead of lowering the bypass valve setting ... doesn't make sense. IMO, the lower bypass setting has something to do with the design and performance of the filter.
 
You could be correct, there is so little information on Motorcraft oil filter specifications. It would be interesting to have a FL500S & a FL820S cut open to compare the medias.
 
Originally Posted By: ZeeOSix
IMO, the lower bypass setting has something to do with the design and performance of the filter.


Based on this, the flow rates seem basically the same: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2508115

That looks to me to be the sort of difference attributed to the surface area of the media, i.e. the larger media of the 820S flows marginally more oil. I think a more likely guess is that it has something to do with the displacement of the oil pumps. I agree that ADBV and filter orientation play no role at all. I've drained every 820S I've ever removed, and they all are holding nearly 3/4 of a quart of oil. My filter sits horizontally.
 
Originally Posted By: JOD
Originally Posted By: ZeeOSix
IMO, the lower bypass setting has something to do with the design and performance of the filter.


Based on this, the flow rates seem basically the same: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2508115

That looks to me to be the sort of difference attributed to the surface area of the media, i.e. the larger media of the 820S flows marginally more oil. I think a more likely guess is that it has something to do with the displacement of the oil pumps. I agree that ADBV and filter orientation play no role at all. I've drained every 820S I've ever removed, and they all are holding nearly 3/4 of a quart of oil. My filter sits horizontally.


Good find.
 
Status
Not open for further replies.
Back
Top