Zongshen RX3 : Unexpected Dead Engine in a deep forest tour

[vickytulla]

Hola; fella riders, I hope you guys are doing great,

I jut finished up reading few threads by spud for trouble shooting RX3 as I just came back from a exhaustive long tour, nevertheless it went excellent but I had to manage a serious problem which occurred in My RX3 along whole tour in order to complete it and come back home on it...

BACKGROUND # The bike creates a "bzzzzzzz" sound when you "ON" the engine cutoff on right side handle grip... for a while when the needles are moving on speedo meter as well.. and then bike EFI red Icon shows up in order to indicate that bike is ready to fire up the engine.. MY bike does the same every time I urn on that button before starting it as well..

PROBLEM# BUT on 3rd day of tour on a fine morning I turned on same button and noticed that sound did not occurred I ignored and continued to load the camp and sleeping bang and fill up the trunk.. finally I hope on to seet and pressed self start butting.. bike did cranked like trying to start up but nothing happened..

I switched on/off the ignition button again but no sound came again... I asked for push start to fellow rider we pushed it but no success..

then I hopped off checked all electric jacks and wires to fine any losing but every thing was firm and fine, i tried ignition switch on/off several times again.. no success..

then we removed the seat got access to EFI component and checked its jacks they were firm as well.. then we tried more on/Off

then I tried 3 cycles on/Off to get any DTC code but no code appeared... indicating EFI is fine.. after half an hour we were sitting and trying to release that the Chinese bike is dead... the bike out of no where created that "BZZZZ" of fuel pump... (no one was fiddling with the bike and bike was assembled and tried to fire up... with no success) the only thing was that bike was switch on and left after hope less attempts...

after we noticed the BZZZZ I went and pushed the start button and it started..

for next 3 days I faced the same behavior ... it will die here ever it likes... now I am home but I have no idea what is wrong with it..

I do plan to dissemble its whole tank and all wires and clean all jacks and wire it up again , check fuel filter, as no error codes are shown till now... so I am pretty sure some things lose in wiring... lets see how much success I get after this exercise..

My question to fellows here is that did this happened to any one else... ?

If feul pump do not BUZZZZ 'z'z'zzzz on start up check what does that indicates ?

[Sullybiker]

Check your ground wire?

[willy dog]

my zong would crank but not fire with dirty battery cable also check purple connector under seat

[Biker_Andy]

I'd check to see if power is present at the fuel pump when it won't start. Bad connectons can cause strange failures but a connection doesn't usually fix itself while knowone is touching it. I suspect the fuel pump was trying to turn but for whatever reason had difficulty and then overcame this resistance eventually making the buzzing. No fault codes will appear from a bad fuel pump either.

[Adjuster]

Yep simple check for power at the pump. Got power but pump not running equals bad pump. No power at the pump start tracing the wiring backwards from the pump until you find the problem.



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[vickytulla]

I am trying to recreate the problem as it happneed in forest, right now while standing in workshop it "BXZZZZ" every time the mechnic on/off the ignition button...

even though we today cleaned all jacks of wires with WD40 and tried to trace any lose wire but every wire and jack was firm and tight already and each time we on/off ignotin it will buzz... so we assembled it back and just about to leave shop i turned it on and there was not more BzzzZZZ ....

but then after few self start atttempts it did started but not able to ide unless i keep a little throtle pushed... I was already late to work so i came back..

so the problem persists...

[vickytulla]

yes we need to do it this way... but we need to first able to recreate it every time to trouble shoot it ...

Originally Posted by Adjuster

Yep simple check for power at the pump. Got power but pump not running equals bad pump. No power at the pump start tracing the wiring backwards from the pump until you find the problem.



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[Sullybiker]

Can you run a meter across the fuel pump electrical connections?

[rjmorel]

Could the ignition switch be bad and not connecting all the circuits repeatedly?
rj

[Biker_Andy]

Originally Posted by rjmorel

Could the ignition switch be bad and not connecting all the circuits repeatedly?
rj

No if the ignition switch was bad nothing would work. The ignition will be a single + wire running multiple places.

Check for power at the pump if possible, the RX3 uses a fuel pump relay as seen in picture.

[vickytulla]

I am just sad my bike now do not start any more and self starts just died the batter too... :( its summer and every body is out there..

i have dismantled the whole tank i noticed while draining fuel there was water contamination as well about a hole glass of water blackish and slimeeeee..

i serviced the fuel pump now i am trying to find professional help.. no idea..

this is 3rd world country almost no efi bikes or technician here..

I have to talk to some car mechanic and make him agree to look into this.. i order odb scanner on aliexpreess i dont know if it will help..

i am getting night mares these days... no sleep..

Originally Posted by rjmorel

Could the ignition switch be bad and not connecting all the circuits repeatedly?
rj

Originally Posted by Sullybiker

Can you run a meter across the fuel pump electrical connections?

[pete]

As said... I would look at the fuel pump relay first...

the buzz when you turn it on is the fuel pump priming the injector/ bringing it
up to pressure so it is ready to go when it is triggered
once you hit the start button..
(well is on a yamaha.. most bikes work the same way)



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[vickytulla]

ok... I am going to change the relay first now for sure... will post again after checking..

Originally Posted by pete

As said... I would look at the fuel pump relay first...

the buzz when you turn it on is the fuel pump priming the injector/ bringing it
up to pressure so it is ready to go when it is triggered
once you hit the start button..
(well is on a yamaha.. most bikes work the same way)



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[artur94]

-Replace / check fuel filter if is not block
- check the full injector if is not block
- Test the pressure in the cylinder
- check exhous if is not blocked

[vickytulla]

Originally Posted by artur94

-Replace / check fuel filter if is not block
- check the full injector if is not block
- Test the pressure in the cylinder
- check exhous if is not blocked

1 - Feul Filter is letting the feul pass and it was clean
2 - How can I check injector by removing it and seeing it if it sprays ?
3 - Pressure was fine I checked it as a the first thing
4 - exhust is not choked as well its fine..

I just got exhusted that day .. will debug further on comming weekend.. Damn thins EFI thing is complicated, I never worked that long to fire up a carby bike...