Can't draw fuel from tank...

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OK so I'm in the process of trying to bring my dad's old vmax back to life... and I was hoping today was the day I'd get'er started back up! Turns out I was wrong. The bike can't draw fuel out of the tank... I'm not sure why, but I even disconnected the fuel filter and tried to draw some by mouth and got nothing. It's clogged? I did a 3-step tank sealing process, did I screw myself and seal my fuel outlet? The bike wants to start so bad, but it needs some gas! Ideas or alternate hypothesis? A way I can get around buying a new tank? Just sitting on the bike trying to get her started has me really excited, I NEED this thing to run.... I don't want to buy a whole new freaking tank and rip out the old one! Thanks a ton guys. - David
 
is the pump cycleing when you turn the key on? if soo then fill the line with gas as it might have lost its prime in the fuel pump, or fill the pump and try

worse case set up a jerry can and try that, that will tell ya if the tank is screwed. also check the vent is open or open the cap on the tank and see
 
I hear the pump clicking away when I turn it on, so that part is running (and I'm assuming working). For filling the line, can I literally just put a little gasoline in the fuel line? Like with a syringe or something? What kind of wire/line could I use to try to unclog the tank if it is clogged? I'll go outside and pop the cap and give it a try right now, I'm not too hopefully anything will come through though :-/
 
There is no movement of anything when I tried to pull liquid up by mouth. It feels like there isn't even an opening on the other end
 
If you used the tank cream & filled the outlet you may need a new tank if you cant open her up
 
I had to replace the tip-over valve on mine because it got clogged with junk. Try disconnecting the tube on the top side of the gas tank and see if you can then draw fuel out of the tank.
 
Sorry, this IS my first time at the mechanic rodeo, what is the tip-over valve. I'm going to go out and try to disconnect the top hose and see what happens.
 
It's a ball-valve that if the bike is laid over the ball moves to the top of the valve and seals the line so that fuel doesn't come out of the tank. If you follow the line from the top of the gas tank you'll find it attached close to the rear cylinders.
 
There are two lines on the top of the tank. One is the fuel outlet that goes to the filter (which sits directly on top of the tank) and then to the pump, and then the carbs.

The other line is a vent. If you follow the hose, it runs in front of the batter box. The tip over valve attaches to the battery box.

Disconnect both lines from the tank. Remove the fuel cap. Put a hose on the fuel outlet and try to blow IN the tank by mouth. If you can't, Your pickup tube is blocked.

If its blocked, I would try to fish a piece of wire in there. Something like a piece of #12 solid copper. Rigid enough to push on but malleable enough to bend.
 
I've already learned a ton on this site.... I mean sadly enough as it is to admit I wouldn't have even been able to tell you what a master cylinder is, let along rebuilt it. So I owe this site a lot. I can definitely NOT blow into the tank. I even tried putting a bicycle pump up to it and it wouldn't blow through, so it must be clogged.... hopefully not with tank sealer. I'll look for some copper wire. Thanks a ton you guys, I'll update you with my success failure. Any kind of fluid I could drop down into the fuel outlet to help try to unclog it?
 
I have used the KBS 3-step on 3 or 4 different tanks with no problems. It does not line the tank like Kreem does. You may have dislodged some junk, rust, deposits, etc that clogged the line to the filter/pump. Or it may have already been clogged from years of sitting. Try the wire cleaning tip previously mentioned. Don't know what you have done to this point but if that line is clear, the fuel filter may be clogged. I would replace that in any event as the bike has been sitting.
 
Well I rebuilt the front brake master cylinder and bled it, the clutch slave cylinder and bled it, changed the oil, changed the coolant, changed the fuel filter and replaced the lines going from tank to fuel filter, and from fuel filter to fuel pump.

I bought some wire, unfortunately what I bought was not able to take the sharp bend down into the tube. I'll have to start again tomorrow.
 
Here is an idea I would try.....Go down to the auto parts store and buy a universal speedometer cable. Sharpen one end of the cable (square end) with a file or bench grinder in the shape of a flat head screw driver. Insert it into the outlet for fuel and push it as far as it will go. I would then cut the cable leaving about 4" to 5" and attach a drill to the end hanging out. Spin the drill and work it in and out a bit as you spin the cable. A speedometer cable is a bunch of small wires twisted together, so spin the drill so the cable will be in the winding mode while cutting thru the sealant. The vent tube on the tank will have to also be opened if its clogged. Just a thought I would send your way..........


I hear the pump clicking away when I turn it on, so that part is running (and I'm assuming working). For filling the line, can I literally just put a little gasoline in the fuel line? Like with a syringe or something? What kind of wire/line could I use to try to unclog the tank if it is clogged? I'll go outside and pop the cap and give it a try right now, I'm not too hopefully anything will come through though :-/
 
If you just want it to run, buy 12 to 18" of the same diameter hose leading from fuel filter to tank inlet and hook that hose to fuel filter and drop the other end of hose into the tank with the fuel cap removed. Make sure hose is deep enough to draw fuel from the tank or should I say tank has enough fuel in it to allow for hose to draw fuel. You could actually ride the bike like this if you pack some rags around hose to keep it in place. You will have to cycle key on/off several times to allow fuel pump to draw fuel from tank to fill carb bowls. Not the safest thing in the world to do but if you are hell bent on testing the bike this would work.............
 
does the pump keep clicking if you keep turning the bike on and off? i assume yes hence you cant start the bike.....once the bowls are full the pump will not click when you turn on the bike. also it wont run long enough to prime the bike hence filling the pump and lines first.

but sounds like you have a clogged line, so blowing in you cannot do that either, take the cap off the tank and should be able to hear the air.

and not to be stupid but it happened before to people........there is gas in the tank right?
 
Gotta be careful with the pickup and vent lines when installing a Kreem style liner. I usually blow air through the lines every 5 minutes or so until its dry/hard enough to stay open on its own. You should be able to poke through it with something as stated previously....
 
Well I went to Lowes today and found in their clearance cart, 12 gauge braided copper wire. It was quite a few feet long but at only $4 for the whole thing, what the hell. Came home, pushed through the fuel outlet and........... Success!!! I could blow air in and even managed to hear my bike start for the first time.... for a few seconds. Then I noticed the fuel gushing out the sides of the carbs! Hah, from one thing to the next. I've got a pretty full week of work, but I'm going to get as much done as I can. How should I start? Literally fuel was coming out the sides (I'm pretty sure from underneath the covers), not out of the drain tubes (I checked the screws, just in case they had somehow been undone and left open). Thanks a ton for everyone's help with the tank, but now I need to figure out these damn carbs
 
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