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Discussion Starter · #1 ·
My goal was to finally get my bike on the road to find problems and dial things in before paint and some other detail work. I spent most of the day checking fasteners, bleeding brakes, checking connections, etc. in preparation for the big event.



Sadly, I couldn't get it to start. No matter what I did, I couldn't get fuel to the carbs. This isn't the original tank, so I haven't used it (or the petcock) before. I pulled the fuel line and confirmed that gas wasn't getting through the petcock. Off came the tank and petcock (no ride today).



Once I got the petcock off, I was amazed to see that NO FUEL came out of the tank! I cleaned the tank and sealed it with POR-15 about a year ago. Thinking that the tank was plugged, I gently stuck a screwdriver up the fuel outlet. Nothing - no resistance to pressure, no fuel, nada.



I am completely mystified by what the problem could be. The only thing that I can think of, which I can't confirm, is that the POR-15 created some kind of bubble (it would have to be a large one) that sealed off the area around the fuel outlet. For that to happen, there would have had to be a low pressure situation within the tank when the POR-15 was setting up. Not sure how that could have happened.



Any thoughts or suggestions?



Jeff
 

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Well there has to be something blocking it inside the tank. But if you stuck a screwdriver in the hole that should clear everything. How much gas are we talking about. A little bit might not let that much flow but over 2 gallons should be a gusher.



Did you remove the fuel strainer when you coated it? if not That's the problem. They are about 4 inches long and jammed up the petcock hole.
 

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Discussion Starter · #3 ·
I didn't have much fuel in it, but enough for something to come out. I can't recall if the fuel strainer was in the tank or not when I got it. I don't think so, but that would be pretty hard to confirm. You're right, though, if it was in there, and in place, that's most likely the problem. That thing would have withstood 1,000 bb's shaken and shaken and shaken, but that could do it.



Would you suggest pushing a bit harder with a screwdriver? The first screwdriver I used went all the way to the handle, so I got a MUCH longer one. It hit something, which appeared to be to be the side of the tank.
 

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I noticed that when I did the por 15 that the sealant that I poured out of the tank bubbled over. I think it was because I spilled a little water in the can so I think maybe that is what happened to your tank. That the sealant bubbled over.
 

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If your sure you have penetrated any seal in the botom of the tank and it still isn't flowing, is the vent in the cap blocked? - that would cause the fuel to not flow if there was a permanent seal. If you open the cap with the petcock off does it flow fuel?
 

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Try blowing air in through the petcock hole to see if the air comes out the filler cap??



edit;

Maybe there is a "Dam" of tank sealer in front of the hole keeping the fuel from reaching the hole. Put the gas cap on and tip the front of the tank up(carefully)to see if any gas comes out.
 

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Discussion Starter · #7 ·
I had the cap off and the tank tipped so that the fuel outlet was at the lowest point - no fuel. However, the cap was on the tank when I had it on the bike...



You bring up a good point, though, and another potential problem. I only have one gas cap and had in on the tank when dispersing the POR-15. Uh oh...



The cap was on the tank when I had it on the bike...
 

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Discussion Starter · #8 ·
I just checked, and I can blow through the vent in the gas cap. It seems a bit constricted, but I don't have anything to compare it to. I stuck a welding tip cleaner in the hole and poked around a bit. No improvement.



I'll play with it more in a few days. (I don't smell like gas now and Mrs. likes that). My schedule probably won't allow to mess with it until at least Wednesday (but probably next weekend). I'll keep you posted, but let me know if you come up with any other ideas/suggestions.



Thanks for everyone's help!

Jeff
 

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Maybe you can shine a light through the cap hole and see what's going on in the back because it doesn't make sense.



Is or was the fuel strainer out?
 

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Discussion Starter · #10 ·
I tried the light but couldn't get a good angle to see to the back. However, I think I'll see if I can see light from the filler through the outlet...



No confirmation either way on the strainer.
 

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I would say that if you didn't take it out yourself then it's still in there. That could stop over a gallon of gas from flowing and even more if it capped over.



You should be able to look at the petcock hole and see either metal or a light plastic tube.
 

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This is what it looks like and is most often pressed into the bottom of the tank and separates from the petcock when it's removed.



 

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You should be able to look at the petcock hole and see either metal or a light plastic tube.
If you need to, sand the end of the bung. Then you should be able to distinguish nylon from metal. Also, if I remember correctly, the ID of the bung without the stainer is about 3/8". The ID of the strainer is about 5/16". (Probably 10mm and 8mm.)



R
 

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I think that I also will have this problem. Removed the petcock from the tank and all that was on it was the plastic tube.







Also was suprised that there was no screen or filtering media at all. So the question is, how do you remove the cemented in filter? Jam a screw driver into it and try to twist it out?
 

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I have had reasonable luck using a Easy-out spiral remover to draw out the petcock filter. You have to be somewhat gentle using it as if inserted and twisted too forcefully, it will expand the plastic end. I just use hand pressure on the twisting and try to withdraw it using a rocking motion and twisting a bit.
 

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I have heard about using bolts screwed into the hole to pull them out but haven't tried it. Usually I take a wood screw and try to screw it between the plastic and the metal. Once it gets in there an ok distance I will remove it and use a pair of needle nose pliers and a slight twisting motion to go around the tub and break it free from the tank.
 

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Uppon closer examination, the screen was still in there! I built a puller useing a 3/8 x16 bolt. Drilled out three washers to 29/64 inside diameter. It worked real slick. Did not have to tap the screen, just screw in the bolt. Now I suppose that I have to replace the screen!















I am glad someone posted this problem before I put gas in the tank!
 

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You can run without them as long as you have a filter between the petcock an the carbs but many would suggest you replace it and run a filter in addition.
 

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On my CB750 Custom I had a secondary fuel filter, in-line between the petcock and the carbs. I believe it was one intended for a recent model Goldwing.
 
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