Fuel priming sound continuous at times. Starting issues

[Mavebrick]

I was working on the bike past few weeks and it has not been started. It was on a tender periodically but not all the time. Tried to start bike again and it has trouble starting. Sometimes i hear the fuel pump priming sound continuously and not at other times. Measured voltage is 10.87 volts though battery tender showing green. Are these symptoms common with low battery? I did remove the connector to the jetronic and reconnect it so am wondering if maybe i messed something up with the connection.

[frankenduck]

You'd have to try REALLY, REALLY hard to connect the L-Jet improperly. It really only connnects one way.

On a K75 the fuel pump should only be running the engine is turning - starting or running.

[Laitch]

Measured voltage is 10.87 volts though battery tender showing green.

The battery seems weak and a battery tender won't recharge it. It needs to be slow charged. If it has been run down a few times, it might not hold a charge for long enough to start the engine even if charging gets it up to 12.6V. Is the starter turning the crankshaft?

[frankenduck]

The battery seems weak and a battery tender won't recharge it. It needs to be slow charged. If it has been run down a few times, it might not hold a charge for long enough to start the engine even if charging gets it up to 12.6V. Is the starter turning the crankshaft?

This is false. For example, a Battery Tender Junior will charge batteries with 3V or greater. (But, as you point out, a battery with multiple deep discharges is usually toast.)

The best thing to do with suspect batteries to have them load tested (for free) at an auto parts store.

[Laitch]

This is false.

On the contrary; it's a conditional truth that you seem to recognize. 

My topic was a weak battery, not one that has simply been discharged. A battery tender is not a shamanic healing device. Its age and model and the ailing battery's history govern its aspirations and abilities. Mavebrick seems be discovering his tender's limitations.

[Mavebrick]

When putting my tank back i only connected the fuel outlet and return but not this other hose to the right back side of tank that is like a little stub. One stub was open and one sealed. It seemed like it was connected to a hose that goes open to back of right footpeg, could this be causing starting issues?

[Laitch]

Way back in the mists of time in Reply #2, I asked you if the starter was rotating the crankshaft. What about it?

The purpose of the two outlets emerging from the floor near the right rear of the fuel tank tank: one is to drain water that accumulates around the fuel tank opening; the other is to redirect vapor from the fuel tank back into the crankcase by means of a hose attached to a pipe mounted in the  forward top of the crankcase. It was designed to meet California emissions standards. Neither of those should have an effect on starting.

[Mavebrick]

Thank you laitch. Yes i believe it is. How do i verify that crankshaft is rotating? Thank you.

[Laitch]

Yes i believe it is. How do i verify that crankshaft is rotating?

If this isn't your first experience with a gasoline engine, you'll figure it out. YouTube is a big help.

Determine the condition of the battery, as frankenduck has recommended. You need it for diagnosis. Uncap the outlet extending from the floor of the fuel tank, put a vacuum-grade hose on it and lead the hose down behind the right foot peg where the other hose is. It's needed to help vent the tank.

[Mavebrick]

Okay will trying to jump start it with a weak battery cause any issues to the electrical system from multiple failed starts and cranks?

[Laitch]

Okay will trying to jump start it with a weak battery cause any issues to the electrical system from multiple failed starts and cranks?

First, check the function of the battery that's in it; if it cannot handle a load, get a replacement, install it and tend it correctly when not diagnosing the Brick with it. Multiple failed starts will discharge any battery eventually. That is why it is important to maintain it correctly when not in service.

If this were my dilemma, I would not be jump starting for diagnosis.

[Mavebrick]

Will do what you recommend Laitch, thank you for your prompt responses. Really appreciate it.

[2000rsv]

Get the battery checked.  Another issue that may show up with trying to start with a low battery is welding the contacts of the starter relay.  Not a difficult repair, just a PITA.

[Mavebrick]

Thanks for the responses folks. It was a bad battery. Putting a new battery in solved the issue and got it started again.