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fuel pump being wonky now

orangeracer

orangeracer

2016-10-19 04:25:00 UTC

Probably user error, but tried lighting the 990 today but no joy. I installed a Rotty intake and air block off, got most of the evil varnish out of the system, flushed out the tank, and installed new fuel pump filters, (old ones were brown). Stuck the tank on temporarily, plugged in the wires and fuel line, reconnected battery. Key on, seemed to go through the pre check ok, it seems there is a quick buzz from the tank/pump. Hit the switch, turns over but no fire. I pulled the fuel line and replaced it with a temp clear hose to make sure it was getting fuel, (wasn't smelling gas from the pipes). After switching to clear, I confirmed there is no gas is going into the fuel hose. I didn't fill the tank for testing, put in about 2 ish quarts/liters. I tried tipping the tank backwards to make sure there is fuel but didn't make any difference. Sorry if this is newbie material, but first bike with a pump/fuel injection. Thanks for any tips!

No. 47

No. 47

2016-10-19 09:06:00 UTC

Did you replace fuel line fully or partly between tank and throttle body?

The OE QR fuel line has to be fully connected and, if only slightly not fully engaged, will prevent fuel flow.

Is the headlamp unit and, therefore, tip over switch up in position?

orangeracer

orangeracer

2016-10-19 22:25:00 UTC

I replaced the entire line between the tank and throttle bodies with a single piece of clear hose so I could see. Bike is upright, headlight as well, so I presume the tip sensor should be ok. I added some more gas just in case it wasn't priming correctly. Didn't seem to help, still no gas in the tube. Despite adding more gas the low fuel light is still on, could that be a hint?

No. 47

No. 47

2016-10-20 06:49:00 UTC

Usually takes circa 3 mins for fuel light to extinguish after refill so, no, don't that's the issue.

Try refitting OE fuel lines and make sure QR connector is properly seated.

orangeracer

orangeracer

2016-10-20 15:05:00 UTC

I ended up in maybe even more of a pickle now. I pulled the pump out to check the connections last night, and I found that the black wire connection was a bit loose at the base, so tightened the spade connector, got it seated and back together. For an experiment, I plugged the pump in without the rest of the tank and tried the key. That seemed to confuse the startup sequence, I figured it was because the other plug from the tank wasn't in. So back in the tank, plugged both back in, key on and now I keep getting partial boot, the speedo will do things like advance the dial 1/2 way and stop. Sometimes get a FI light, but no distinct blink patterns I can tell. Le sigh.

I guess I need an ECU cable thing to clear whatever error it's stuck on? I tried unplugging the battery, waiting a few mins but didn't help.

Also, how do I route the front and rear tank vents now that the canister is gone?

DribbleDuke

DribbleDuke

2016-10-20 16:04:00 UTC

This might sound counterintuitive but make sure that all electrical connections at the battery are good. Especially the grounding. You also need to be sure that the battery is producing sufficient voltages. What you described in the last post can be directly attributed to poor electrical grounding. Trust me I have seen the wanky clock start up too many times. Slow down and be meticulous.

No. 47

No. 47

2016-10-20 16:07:00 UTC

Doubt whether it's a TuneECU issue - is battery on trickle charge 'cos not being fully charged may explain clock behaviour.

Fuel flow issue, I'm guessing, may be due incorrect re-assembly ie pumping back into tank as path of least resistance.

Front tank bent tube slopes back to rear of oil tank and then vertically drops - rear simple drops behind and cable tied to vertical frame tube.

orangeracer

orangeracer

2016-10-20 20:54:00 UTC

Thanks, a co-worker/drag car enthusiast suggested putting the battery on a charger even if the voltage looks ok. Sure enough, a couple hours on the tender and it ran through the boot fine. Still no gas in the line though, grrr... I'll put a meter on the pump plug tonight and see what readings I get. Not ruling out bad reassembly just yet of course, would like to see if there is something else before I take it apart again.

orangeracer

orangeracer

2016-10-21 07:05:00 UTC

AHA! Meticulous won the day. Did lots of meter testing, grounding, pulled the pump, found that the motor was working at it's source. But not at the connector plug... Finally discovered that the loose black wire I mentioned earlier, I sort of plugged into the wrong connector at the base of the pump... so cue your favorite Homer Simpson sound...

Anyway got that sorted, tested again before re-assembly, pump motor went whirrr with the key on. Pump in, tank on, plugs attached, key on, then 98 octane Sunoco GTX rushed gleefully into my clear temporary fuel tube. No need to stop there, so hit the switch and FIRE! Lots of noise, giggling and *almost* got it shut off before I woke up all the dogs in my neighborhood, (just have an open header for the time being).

Still an educational process and thanks for the input. Even if I had rebuilt the pump 100% from the beginning, I'm sure I would have been bit by the just a tiny bit low on battery voltage bug in the future.