do i need to use a fuel filter?
- Thread starter jowkwondo
- Start date
i don't use them. but i make sure my fuel is clean, my tank is clean, and i usually end up rebuilding my carb for one reason or another every month. there's always a bit of dirt in my float bowl, but i've never had a problem with clogging.
it is a good idea, i just haven't found a fuel filter i like. it's more of a cosmetic issue for me.
it is a good idea, i just haven't found a fuel filter i like. it's more of a cosmetic issue for me.
The stock tank has a tiny 'screen' fuel filter in the shut off valve; That's usually good enough. (Unless the tank is really dirty or rusty inside.)
Mine doesn't have any screen filter. I've taken the valve apart and there's nothing in there and I can look into my tank and there's no screen in the valve hole, either...
oh yeah, i forgot about that one. i have the little screen in mine, and in the custom tanks i build, too.
It should've come with the engine kit!!
If you don't have that?, then you need a 'in line' filter!! I like the small filters that are for weed wackers... They're made for gas/ oil mix.
my screen filter on the fuel shut off valve doesn't seem to let fuel fill the line,... it does come through but very slow,...
I haven't started this bike yet (1st one, got a few problems I'm fixing) but I'd like to see that line full of fuel down to my next in line filter,... will the carb pull or suck fuel into the line when it's started or is this all gravity fed,...?
I haven't started this bike yet (1st one, got a few problems I'm fixing) but I'd like to see that line full of fuel down to my next in line filter,... will the carb pull or suck fuel into the line when it's started or is this all gravity fed,...?
These engines can run fine with just a trickle of gas through the line.
If you 'hot rod' the bike?, then you might want to step up to a better shut off valve & filter.
your petcock mite be the real problem, when i turn mine to off, which is supposed to totally block fuel from coming in/going out, it basically still flows freely, just at a slightly reduced rate from when it's open like the way it's supposed to be.
maybe take your fuel line off, take the bike outside and slowly play with your valve to find the sweet spot and mark it with a sharpie, thats what i did to figure mine out. guessing these things aren't made with the highest quality control standards.
I found out that without the tiny little in tank filter that if its broke or missing then the very tiny passages in the stock petcock will simply clog up. My in tank filter fell apart right away and I had to go to a better petcock with bigger passages inside it solved the problem there as I had to take apart the petcock and found just a crumb stopped it up.
Then I went with a good inline filter and never had to touch anything again.
http://motorbicycling.com/f34/your-bike-losing-power-top-speed-24880.html
Then I went with a good inline filter and never had to touch anything again.
http://motorbicycling.com/f34/your-bike-losing-power-top-speed-24880.html
Couldnt use the stock intank filter because on my build the tank wasnt able to sit flush with the stock valve sticking straight out. Ended up using a brass 90 and putting the petcock on that with an after market inline filter from autozone. Works great and dosnt cut out at top speed, it actually screams. I will always recommend running a fuel filter especially an after market one that will actually filter out particles unlike the POS that comes with the kit.
One of the first things that should be done when starting a motor installation is to carefully inspect the insides of the kit supplied fuel tank, before it is installed on the bike. I've yet to see one that couldn't benefit from a good cleaning. They come from China with rusty insides that will eventually clog even the best filter. Methods for cleaning the tank have been posted here numerous times. Acid baths, rocks and or sand, specially formulated rust busters, etc.
Another common misconseption is that you need fuel flowing to the carburetor like a fire hose. If it flows a steady stream,even a small one, it is enough.( the only exception is a highly modified engine but even then I seriously doubt that it could consume fuel faster than a steady stream.) If it just drips, then you have a problem. There have been reports of petcocks that were not fully open when the lever is in line with the valve and require the builder to 'find' that spot where fuel flows the best. The same for a fully closed valve (petcock). Something else to keep in mind when replacing the kit valve with an aftermarket style is the threads in the tank. They are a metric machine thread, not pipe threads as are most commercially available petcocks. A 1/8" pipe tap can be used to alter the kit threads as long as you don't run it in too deep.
As for fuel filters, don't rely on the fuel you get from most gas stations to be pure or by that I mean, crud free. If you mix your fuel in a container, after several fills take a close look at the residual gas left in it and you'll see some trash. That stuff will eventually build up in your bike's fuel tank and then either the carb or the filter. I'd rather catch it in a filter than having my needle valve stuck open with crumbs. Bairdco's advice is sound... filter your fuel before it goes in your tank. That's good insurance.
Tom
Another common misconseption is that you need fuel flowing to the carburetor like a fire hose. If it flows a steady stream,even a small one, it is enough.( the only exception is a highly modified engine but even then I seriously doubt that it could consume fuel faster than a steady stream.) If it just drips, then you have a problem. There have been reports of petcocks that were not fully open when the lever is in line with the valve and require the builder to 'find' that spot where fuel flows the best. The same for a fully closed valve (petcock). Something else to keep in mind when replacing the kit valve with an aftermarket style is the threads in the tank. They are a metric machine thread, not pipe threads as are most commercially available petcocks. A 1/8" pipe tap can be used to alter the kit threads as long as you don't run it in too deep.
As for fuel filters, don't rely on the fuel you get from most gas stations to be pure or by that I mean, crud free. If you mix your fuel in a container, after several fills take a close look at the residual gas left in it and you'll see some trash. That stuff will eventually build up in your bike's fuel tank and then either the carb or the filter. I'd rather catch it in a filter than having my needle valve stuck open with crumbs. Bairdco's advice is sound... filter your fuel before it goes in your tank. That's good insurance.
Tom
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I removed the petcock screen and added a clear inline filter from my local auto parts store. Some of the tanks paint had flaked into the tank and i can see it swimming in the filer.
i got it at autozone and it comes with the hose end pieces filter screens are cleanable and replaceable.
Are fuel filters necessary? My fuel filter broke and I don't want to buy another! I just want a simple reason and explanation.
Fuel filters are very inexpensive to start with. However, just run your engine without one. Then when your carburetor clogs up and you have to rebuild it you'll understand why a fuel filter is necessary. There's a small wire mesh screen in the carburetor the will catch a lot of the debris but some will still get through and clog you jets.
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