Donaldson Air Box off Kawasaki FX691 question

7394

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I picked up an FX691V air box 'slightly used' and after clean up, I'm testing the Donaldson Outer Air Filter # P821575 that came with it. Just to be sure I order the correct new one, when ready.

Question: Is it normal for the outer filter to fit into both cup ends (for lack of a better word) of the canister & end cap with only approx 1/8" or so air gap on each side outside of the filter ? Actually both sides combined is approx 1/4" or so.

Filter is 10.75" long filter, & O.D. is 4.25"

To me seems like that may be a little tight in the canister cups, but uncharted waters for me here. Appreciate any input.
 
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Darryl G

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I picked up an FX691V air box 'slightly used' and after clean up, I'm testing the Donaldson Outer Air Filter # P821575 that came with it. Just to be sure I order the correct new one, when ready.

Question: Is it normal for the outer filter to fit into both cup ends (for lack of a better word) of the canister & end cap with only approx 1/8" or so air gap on each side of the filter ? Actually both sides combined is approx 1/4" or so.

Filter is 10.75" long filter, & O.D. is 4.25"

To me seems like that may be a little tight in the canister cups, but uncharted waters for me here. Appreciate any input.

P821575 is the same part number as the original filter for my 691V Donaldson filter :) I just pulled it to check. I believe it's supposed to be a tight fit so it stays in place.
 

7394

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Thank You for checking ! It fits fine on the I.D. Inside Diameter, where it pushes on to make the seal.

I am referring to the outside of the filter surrounded by the cups inside the canister, the air-gap surrounding the filter.
 

Darryl G

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I see. Well, it appears to be the correct primary filter so I guess that's just their design. Air doesn't need a lot of room to move, ya know.
 

7394

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Appreciate the input, Agree about the air. Upon inspecting the used P821575 filter, it is mostly dirty where it is open in the canister. The ends seem visibly cleaner. That's the nature of my concern.

I'm working on a conversion for my FR651V Kaw.
 

7394

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Appreciate the input, Agree about the air. Upon inspecting the used P821575 filter, it is mostly dirty where it is open in the canister. The ends seem visibly cleaner. That's the nature of my concern.

bump
 

BlazNT

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Not sure what you are looking for but air moves through the path of least resistance. So as the dirt collects and the opening it will move to the cleaner spots till it gets dirty and so on. This is not the exact process but I think you get my point. Also, remember it will only take in what it needs. The entire filter is not used when new and clean. Just the space it needs to draw in the right amount of air.
 

7394

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BlazNT- Thank You Sir, that sums it up nicely. My concern was the 1/8" or so air gap (per side) around the outer filter in the canister cups. Seemed to me kinda tight.

Guess I can check this obsession off my list now. FWIW: I'm trying to do my research to do this swap one time, with good end results.

Darryl- Thank You as well Sir.
 
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