XJ 700 Dies at half tank

Hey guys,

I recently purchased an 86 XJ700. I am not new to Maxims or Yamaha for that matter. I have an XV750 that I've ridden daily for years now.

Any way, the XJ dies on me after about a half tank of gas. I look in the tank you see a decent amount of gas.

I pull off for gas and it fires right up after I fill the tank. The reserve on my bike doesn't seem to engage when I turn it on at the petcock.

Any thoughts?

 

There could be crud blocking the reserve passage. Rebuild the petcock.

 

While rebuilding the petcock go ahead and pull the fuel pickup out of the tank and take a look at it also. Something may be blocking the pickup. I have a 85 xj700n and I don't get to reserve until well after 1/2 tank. I think the tank holds 3.4 gal and reserve is .8 gal.

 

Thanks guys!

Tabaka45, where is the fuel pick up in the tank, and what does it do?

 

Fuel pick-up is part of the petcock assembly. Turn the tank over and pull the two bolts. The tube is on top of the petcock. The sending unit is the other thing that has the wires. That just tells your fuel light when to come on.

I'd pull it the petcock, Clean it, rebuild it, and thoroughly clean the tank, too, while you're at it.

Dave fox

 

Also make sure your tank vent is clear and working.

 

(and your tank vent is in the cap....read up on disassembly)

BUT - if that were the issue, it should manifest itself LONG before the tank could get to half tank. Ai'm assuming this has been a consistent issue at half tank, not a one-time occurrence. ( I know, never assume.....) if it's a tank vent issue, it usually occurs within a few miles. It can also be diagnosed easily boy simply opening the cap to see if it releases the vacuum lock that was causing fuel not to flow enough

Dave

 

Be careful when you pull the fuel pickup. The part inside the tank is plastic and can be easily broken. Just pull it straight out. Replacements aren't cheap.

 

Yes, the hole is not much bigger around than the top of the sensor