Which fuel filter??

[65oldsboy]

I just changed out all of my fuel lines and added inline fuel filters (between the airbox carb boot as suggested in the tech tip). The problem is that the filters I bought from Bike Bandit are too large (diameter) to fit down very far between the boots. I didn't notice that there was any problem until I was ready to make the final connections to the petcocks. When I pushed the back of the tank down, the petcock outlets were right at the fuel filters, which caused kinks in the fuel lined - bad. A trip to Autozone and Advance Auto Parts yielded only larger than what I already have automotive filters or tiny filters for lawn mowers. All of the automotive filters and the ones I bought from Bike Bandit are folded paper filters. The little lawn mower filters are just fine mesh screen filters. I know these will fit but I'm afraid they will not be sufficient to keep small particles out of the freshly rebuilt carbs. Will these be sufficient or should I keep trying other auto parts stores until I find something better? Or, can anybody suggest some filters that will fit?

[cywelchjr]

Napa used to have some small cone shaped ones. You also should run a little extra line and cross connect them (right petcock to left carbs and left to right), to give more slack and make this less likely to happen. Plus it makes it easier to just turn the tank about and set it where the seat would be when tuning the engine.

[natemoen]

I use some small ones I found at O'Rileys. They are even small enough that I can slide them in between the boots on the aribox.

[dbeardslee]

Do you still have the octy? If not, you can point the fuel T's down, and run the lines underneath the air box boots. The lines cross underneath, and one comes up between the boots for 1 & 2, and the other comes up between 3 & 4, and they'll point straight at the petcock taps. When done this way you can use some pretty big filters. If you leave the lines a little long, you'll have enough to turn the tank around backwards and set it where the seat mounts, and run the lines straight back for syncing and adjusting carbs. The only down side is you have to remember to turn your petcocks on and off. With the octy it can be a royal PITA.

On the fuel filters, you might want to be careful with plastic filters - some have a tendency to melt and deform - particularly if you run seafoam regularly although they've been known to do it just from the ethynol in gas. I prefer the type that use the mesh internally, as opposed to the type that have a paper element. The paper doesn't like water, and they will plug up quickly if they come in contact with it - like if there's some in the bottom of the tank and you switch to the reserve position. Personally I like the NAPA FIL 3027's (same as a wix 33027). They have a mesh element, and housing is made out of metal. They flow plenty of gas and last a long time, but they're a bit large to use with an octy.

[65oldsboy]

Yeah, I am still using the octy. My petcock rebuild kit came with an octy diaphragm. I figured since I already had the parts to rebuild it, I would just go ahead and use it. It sure does make for a rat's nest of fuel lines though.

I hadn't heard of the plastic filters melting from alcohol in the fuel before. That has got to really suck. Speaking of melting, isn't the mesh filter material made of plastic too? Wouldn't that be just as likely to melt? I bought a couple of the really small lawn mower filters with the mesh filter material. I might put one in a bath of seafoam and gas (using A LOT of Seafoam) just to see what happens before I install them. I did stop at Pep Boys last night on the way home from work. They had nothing even close to working. There is a mom and pop auto parts store not too far from work that I will try tonight. It really shouldn't be this hard to find a suitable $5 part.

[dbeardslee]

Speaking of melting, isn't the mesh filter material made of plastic too?

Can't speak to all of them, but the Napa/wix uses a wire screen and filters down to 50 microns (.05 mm). On the gas/ethynol/seafoam - I ran some Z1 plastic filters for about 6 months, and when I took them off they were deformed but not yet leaking, so you might need to let them soak for a while before you notice it.

[dbeardslee]

I was just re-reading the thread and it occurred to me that if you do what Cy's suggesting and try running the lines down between the boots and then back up you might be able to accomodate the larger filters under the boots, as well as making it easier to get the kinks out without ditching the octy. I haven't tried it personally, but it might just work. JAT

[65oldsboy]

I did loop the fuel lines and cross them under the boots. In reading the tech tip, it states that there is the possibility of having an air bubble trapped in the filter if mounted sideways. That is why I wanted to have them mounted vertically, between the boots. I think I also read (maybe a post from TC?) that the fuel line loops shouldn't be too long or go below the float bowls because it is a gravity-fed fuel system without a fuel pump. I'm probably making this way more difficult than it needs to be.

[dbeardslee]

I've got mine horizontal, and have never had a problem with them. As far as the loop going below the bowls - I think that's nonsense. Fredintoon's post on pascal vases illustrates what I mean pretty well - pascal's principle basically says that the fuel is going to rise as high as the fuel level in the tank, regardless of how low the loop goes.

[Axel]

[65oldsboy]

I've got mine horizontal, and have never had a problem with them. As far as the loop going below the bowls - I think that's nonsense. Fredintoon's post on pascal vases illustrates what I mean pretty well - pascal's principle basically says that the fuel is going to rise as high as the fuel level in the tank, regardless of how low the loop goes.

Well, that pretty much does it for me. I'm going to use what I've got and see how it works (with my Bike Bandit filters in a horizontal orientation UNDER the carb boots. Glad I bought 20 ft of fuel line. Thanks for all of the posts. I HOPE THE PLASTIC FILTERS DON'T MELT!!??!!

[cywelchjr]

Ah yes, those are the ones *I* like. They filter just about anything out, and don't seem to restrict things too much, and they fit in there without too much cussing and swearing as long as you cross them. And yes, don't worry about dropping them below, as long as the fuel in the tank is above the fuel in the bowls, it's going to flow unless something is plugged.

PS, I don't think mine ever actually filled with fuel, they always had air in them. But with my new tank (no rust and good tower filters) I am running without filters right now with no troubles. However, next time I do major fuel system work, I'm putting filters back inline.

[dbeardslee]

Those look exactly like the ones I had the deformation problem with. I tried the big ones, and the small ones, and they both deformed. I'm kind of a seafoam and acetone junkie though, so maybe that had something to do with it .

[natemoen]

Those look exactly like the ones I had the deformation problem with. I tried the big ones, and the small ones, and they both deformed. I'm kind of a seafoam and acetone junkie though, so maybe that had something to do with it .

Are you still running about one ounce of acetone per tank?

[dbeardslee]

I don't want to hijack, but yup. I carry a little one ounce bottle, and add it when I gas up. I run it in my lawn mower and chipper too. Last year we had a hurricane that blew through (literally - don't see that much in ohio ), and I had all kinds of tree limbs to dispose of. The chipper was having a tough time with some of the larger branches, so I added a little acetone to the gas. It noticeably improved its performance. Now in addition to seafoam I put in the 5 gallon lawnmower gas can to stabilize the gas, I also put an ounce of acetone.