Fuel filter backwards

[imdying]

Typical nylon fuel filters, translucent, non rebuildable, RYCO, FRAM etc. They always have a flow arrow moulded onto them, denoting which of the two connections is inlet and outlet.

What happens if you try to run one in reverse, against what the marks indicate is the correct flow?

[avgas]

Most still work......but restrict flow a little bit.
We used to have issues with em on LINX CIJ printers. If you got the flow round the wrong way the pump would either go up in pressure, or more MEK would enter the mix.
Depends on the internals a lot. Some internals are just a simple filter membrane, and some are like those bait catches with a series of "one way" chambers.

errrr why?

[imdying]

It's a typical nylon bodied filter, the filter media itself it just a barrel shaped concertina paper element.

The why is because space is limited, but a near perfect item is readily available, just with the inlets backwards to what I really want.

[Crasherfromwayback]

, just with the inlets backwards to what I really want.

Suck it (not literally) and see!

[imdying]

Yeah, I might make a mixture of sand and kero, then get another one, and check the flow rate of it in each direction over 20 litres of silt.

Looks to me that there's probably not much in it, and it's a bike that gets more than regular maintenance. But with gravity feed and two strokes it pays to be careful.

[Crasherfromwayback]

. But with gravity feed and two strokes it pays to be careful.

And quick on the clutch lever!!!

[imdying]

Yeah for sure. I've tried to mitigate that as much as possible with dirty big warning lights hooked into the EGT and detonation detection system etc, but you I bypass all the benefits of that by fucking up the install of a $2 fuel filter.

[Crasherfromwayback]

Yeah for sure. I've tried to mitigate that as much as possible with dirty big warning lights hooked into the EGT and detonation detection system etc, but you I bypass all the benefits of that by fucking up the install of a $2 fuel filter.

Some of my most expensive engine failures have been due to a failure of the smallest bits!

[cs363]

It's a typical nylon bodied filter, the filter media itself it just a barrel shaped concertina paper element.

The why is because space is limited, but a near perfect item is readily available, just with the inlets backwards to what I really want.

It will work, but won't last as long and may clog up quicker as you have a smaller area for the shit to collect. Generally they are designed with the flow going from the inside of the filter media to the outside, the inner cavity providing plenty of room to collect crap, running it reversed means the crap will collect on the outside between the filter and the body.

Are you sure you can't find one that works for your application though?

[imdying]

Cheers, that's pretty much what I figured. I might move to a smaller filter per carb line rather than the one collective one; this was just such an artful solution it was worth a look.

[F5 Dave]

Have you seen those Right angled filters? They are a solution looking for a problem, but I bought one as I'm expecting to find a space issue at some stage. Would have been good on my old GSs back in the day.

[LBD]

. Generally they are designed with the flow going from the inside of the filter media to the outside, ?

The fluid flows from the outside in....inside the concertina paper is a cylinder that prevents the element from collapsing when blocked.

If you flow it in reverse, and the filter eveltually blocks the paper element can rupture open and allow the trapped dirt past

[cs363]

The fluid flows from the outside in....inside the concertina paper is a cylinder that prevents the element from collapsing when blocked.

If you flow it in reverse, and the filter eveltually blocks the paper element can rupture open and allow the trapped dirt past

Oops, sorry yes you are correct - I got it arse about face, that'll teach me to go on memory - checked the ones I still have in the shed tonight :) (memo to self: Must not post when distracted...lol). However, whilst it's not advisable to run them in reverse as previously discussed and noted above it is possible to do so which was the original question.
And I agree, in extreme cases you could run the risk of rupturing the filter, though I would imagine that would be more of a risk on a pump fed filter as opposed to a gravity fed one as in this case.