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So i just bought my first bike. Yzf600r. I dropped the bike.not hard. After that my fuel pump started leaking. Me and my buddy cleaned my carbs and put a new fuel pump on it. The pump is pulling fuel but my bike isn't firing. It'll crank if i pour gas directly into the carbs but only for a couple seconds and it takes it about ten seconds of pushing the starter to fire. Any suggestions on what's going wrong?
 

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" It will crank if I pour gas directly into the carbs" What does that mean exactly????To me , cranking an engine means that the starter rotates the engine. Are you saying that this does not happen unless you pour gas directly into the carbs???
 

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Exactly. If i do not pour it directly into the carbs, it won't crank. It's a fuel issue.
There is more to ignition and running than just the starter motor running and engaging the crankshaft.

What I suspect Slumlord means is an engine "turning over" and an engine "cranking" mean the same thing. The starter is working, engaging the flywheel and rotating the crankshaft. But until the engine "catches" or "starts," it's only cranking or turning over. The cranking and the turning over are the mechanical rotation of the engine before it catches or starts.

So it makes no sense that fuel has anything to do with your engine cranking. What you likely mean to say is that the engine will not start / catch unless you pour fuel in the top of the carb while cranking. If that is the case then, yes your problem is fuel related.

Words and phrases have specific meanings, when someone is trying to help you diagnose a problem, especially when they themselves cannot confirm the issue, they must rely on your words alone, so it is very important to use the right words to describe the situation.

So does your engine crank when you use the ignition system? Meaning does the engine rotate as it should? If yes then it cranks fine.

Or is your engine failing to start while cranking unless you add fuel directly to the carb?

Or is it something else altogether?
 

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Wow RKB

What an articulate post. You will go far...

Anyway, now I think i understand what the OP is after. As I understand it, the carbs are fed by a fuel pump at probably somewhat low pressure. I have a 1983 Magna like that. It took many 10 second cranking cycles to prime that fuel pump because of air in the lines.

Doing two repairs, fuel pump and carburetor at the same time leaves us with two variables.

First the carbs. I would propose that you get a small slave fuel tank and suspend it above the carbs. That way you would get a continuous feed of low pressure gas just like the fuel pump puts out. If the bike does not run at this point, I would suspect that the float level is incorrect or the needle and seat are not sealing and that would cause flooding just like a high float condition.
Some floats are adjustable and some are not. Also,sometimes floats get gas inside and sink below their intended level. It is much more likely that the needle/seat are not seating properly than anything else, based on the fact that they are wear parts and also that dirt can mess up the seal..

Since your fuel pump is new, perhaps the line has some air in it or the petcock from the tank is not allowing fuel into the pump. I am sure that you can detach it and test it in some fashion to confirm that it is working.
 
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