Grayowl stated in Reply #18:
"Checked at AutoZone and the filter package states it is a Duralast FF7144DL universal filter that is made in China."
Here is a picture of the same part number filter that I purchased at my local Auto Zone and it is imprinted "Made in Israel" followed by the number "1212"
It appears that Auto Zone's part numbers may not be useful for performance comparisons if the parts in the package may come from different manufacturers in different countries. I haven't installed mine yet, so I can't report on how it works.

This thread gave me a headache ! How can anyone can make life so complicated. Life is what you make of it,....I keep it simple. But then, I don't let "petcock paranoia" get me either. And I don't use a filter that filters smaller material than what could ever hurt anything in the fuel system. And it fits perfectly, downhill all the way !

 
Yes Routy, you have added a small flat section of fine metal screen to your fuel flow.   This device was intended for riding lawnmowers and it would indeed be an improvement for a system that had no screen in it at all, like a B&S riding lawnmower.

So now you have a large fine plastic mesh screen up inside your tank on your petcock and a small section of the same sort of mesh, made out of metal this time, in your fuel line.  You have doubled up on your 100 micron protection and you have made sure all solid particles are less than 100 microns.   You will never find sand inside your float bowl ever again.  It will be in your tank and in your little round filter instead.

The mesh filter manufacturers all claim that they can stop 150 micron particles (some claims go as low as 100 microns).

They make no claims for stopping water (because the screens can't).

Lastly, if we occasionally block up the larger screen sections up in the Savage's tank, how long will it take to clog up the little round disc of the same sort of material in the fuel line?   Do you pull it and clean it periodically or wait until whenever the upper screens plug up / varnish up?

But you are right, it is all part of 'petcock paranoia'.           I'm paranoid that my vac petcock is going to strand me in the middle of a busy 6 lane expressway ....

Charon made a statement that his scooter fuel filter wouldn't pass enough gas when his tank went low -- now he is back checking his statement and discovering more about it.   We are all learning and discovering new stuff.   We have quantified how much gas a Savage uses (0.4 cups a minute normal "average" riding) and have set a goal of a cup a minute as an acceptable flow rate at full tilt boogie speeds.  

Now we have a fuel filter test that can be used (wait until you are in reserve, then pull your fuel hose from the carburetor nipple, get your cup and wrist watch ready and throw your petcock lever over to go and see how many seconds it takes to get your cup full -- less than 60 seconds is a pass, more than 60 is a fail)

GreyOwl has an issue he had attributed to his filter, now he is learning more about his petcock because apparently it isn't his filter as his filter (if it is the same as Charon's #3 filter) is easily capable of filtering at like twice the rate our bike needs at full tilt boogie.

And you are right, we are all being silly wanting that big clear sided filter bowl up under the edge of our tanks so we can instantly SEE what's what when our bikes malfunction and stop us by the road side.

Silly us ....

Silly me ....

 
Routy, that was a good answer -- shame you tongue was in your cheek.



Metal parts, too big -- screen would stop those.  Glops of bubble gum rubberitus, mebbe stopped, mebbe oozed right on through.

Sad thing is your bike wouldn't be running well enough to drink it into the carburetor, now would it?

You'd already be hit by the big Ford Truck by then.


Petcock war is declared on a separate labeled thread, it's winter time and time fer debatin' stuff again.

I found it interesting that in the writeup on Honda's CH80 (www.motorscooterguide.net) one of the criticisms was its lack of a fuel filter. It was strongly suggested that a filter be added. The rationale was that a lot of those scooters have sat around for a while and are being resurrected, and they are likely to have dirt and/or rust in the tanks. I bought mine, a 2007, with 4.4 odometer miles as a used unit from a dealership. I looked in the tank using a flashlight, and at least visually it is spotless. However, after a thousand or so miles of playing I decided to add the filter, and it caused trouble.

Also interesting, the first year of production was 1985 and it had a filter. The filter was dropped after the first year, but I have found no explanation. Did Honda decide the filter was not needed? Or did it give trouble?

Here's the filter we used on both Double RYCA Build bikes.  They seem to have no trouble flowing enough fuel. I had mine up to about 85 for several minutes just to keep up with traffic on I-85.







http://www.knfilters.com/search/product.aspx?Prod=81-0261

My third test was the Briggs & Stratton filter. I did as in the second test. I held my finger over the outlet, filled the tank, unblocked the outlet and started the stopwatch. This time flow started, albeit slowly. Then apparently an air bubble exited and flow sped up to normal, taking a total of 88 seconds to empty the tank. The filter never filled with gasoline. No photo attached of this one, as it is the same as the last time. Last time when I "primed" the filter it took 74 seconds. I think the difference is the slow flow until an air bubble exited.

My fourth test was the same as above, with the last filter. This time the flow started quite slowly, then I could see an air bubble in the fuel line above the filter start to move down. When it got into the filter body flow speeded up, and the total time was 113 seconds. Last time, with the filter primed, it took 74 seconds. The photo is of the last filter, but taken from the side opposite its label so as to show pleats.

As a final and very unscientific test, I blew through each of the filters. There was no noticeable difference when blowing from inlet to outlet or from outlet to inlet, so apparently there is no one-way valve. But the Briggs filter seemed least restrictive, followed by the last filter, and the first one (TW FASTEX VISU FILTER) was noticeably more restrictive. These differences can be attributed to filter media area or to filter restrictiveness (micron filtration) or both. I have no way to know.

I did not measure in "cups" and do not intend to do so. In fact, I didn't measure the volume at all, except that my little tank holds somewhere near a quart. My measurements can be approximately translated to gph by dividing the seconds per tank into 900, or gpm by dividing the seconds into 15.

The main conclusion I reached, which will probably require further experimentation, is that none of the filters can be counted on to prime from dry unless the inlet is lower than the outlet, giving the air in the filter a chance to be pushed along the fuel line to the carburetor. This might also be dependent on the diameter of the fuel line, but I only used 1/4" ID lines. I think the air in the fuel line above the filter (introduced when the line is cut and the little bit of gas drains out) combined with the air in the filter cuts off the fuel flow at the very low pressures involved.

Once the flow got started, I think any of the filters would flow enough to satisfy the demands of the S40/Savage, which only requires about 3 gph at full power. My worry would come if the fuel system were run empty (forgot it was in Reserve or Prime). From dry I would worry the filter might not restart flow.