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Discussion Starter #1
Replaced my fuel pump.
New pump working well but bike will not start. Checked delivery pipe and fuel is pumping through well. I noticed a trickling noise in the tank and could see the back flow pipe in the tank was pouring the fuel back into the tank, is this correct?
I pulled the delivery pipe off underneath the tank and the fuel is pumping through therefore going into the carbs. The bike turns over but fails to start as if it has run out of fuel.
I used quick start spray in the top of the carbs and the bike fires up v briefly.

Any ideas?

Added to my frustration I
2. Removed the delivery / fuel tap under the tank......big mistake! I cannot reconnect it to the tank tightly enough and so the fuel leaks through. I have tried to reconnect the nut to the tank then the tap to the nut but the thread will not bite tightly enough hence fuel leaking out. I think the thread on the tap is mashed up does anyone know where I can buy a reliable replacement. One offered on ebay is for 1997 model.
 

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those taps suck. the outlet tubes crack out as well - they're a "don't touch unless you have to" part.

used on all 91 - 97 carb ss.

float bowls full of water? carb inlet filter blocked? chokes not working?
 

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Is the crush washer still there on the tap?
I also try and touch these as little as possible except if you never use it it will seize up.

Check fuel in the carbs via the drains, better yet open a drain and then verify you are pumping fresh fuel. If the bowls are full and the bike is not consuming fuel it should all go back to the tank.
Once you know you have good fresh fuel in the carbs, if it still will not start check the plugs to make sure you have spark and no fouled plugs.
If you have good spark and still no start you are likely cleaning pilot jets.


Or you could make sure you are not running the pump backwards , it is easy to mix up the pump wires and cause the pump to run in reverse. Don't ask me how i know...lol
 

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My recollection is cloudy, but I purchased the replacement Ducati parts for my '92 and something didn't fit. I don't recall if it was the tap, or nut but something didn't work so I ended up reusing the old parts with new crush washer. I installed a secondary valve and just leave the one on the tank open.
 

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I too have installed an inline petcock, My reason for doing so is that I have installed a solo tail section so lifting the tank to turn the stock petcock on & off is a pita, with the stock dual seat it is no big deal but with the solo tail you have to remove 4 bolts & I am not going to do that each time I ride the bike
 

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Did someone reverse the fuel lines and end up with return “ pill” in the feed line, or no pill at all ? Either would cause starvation or low pressure. Examine the lines for signs of kinking when you close the tank.
 

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Did someone reverse the fuel lines and end up with return “ pill” in the feed line, or no pill at all ? Either would cause starvation or low pressure. Examine the lines for signs of kinking when you close the tank.
I may be completely wrong here--But my fuel lines on my 91 900SS --I have a line from the main fuel tap, another going from the return line nipple on the tank--Both of these go into Y connector--with a single line from the end on the Y to the carbs---So if you have a line to the carbs back to the Y connector then the other 2- ( fuel tap & return) should not matter which goes to the fuel tap & return. when you look at it it's really simple
 

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There is a jet (pill) in the return line which limits return flow. Without it too much fuel goes back to the tank , or if someone mistakenly put the return line with the pill on the feed past the junction, fuel flow to the carbs would be restricted. Pretty sure ‘91 up Carbies all had them.
 

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the jet part # 13210061 item #32 in my parts illustration absolutely acts as a restrictor installed in the return line and is present and accounted for in my '95 USA version 900SS/SP.
 
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