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Discussion Starter #1
Hi all, I have a 2007 ish F4 R and after the odd moment of it not turning over very well when hot i decided to upgrade the battery leads and treat the old girl to a new battery ,
the new leads were fitted and a fully charged new battery was installed and so to start up,I switched the ignition on and the usual cycle started ie pump prime dash sweep , hit the starter button and she fired up ,however I thought she sounded to have a bit of a missfire so removed the tank to check if all the connections were sound, this seemed to be the case so refitted the tank and hit the starter again and it started but sounded realy rough now so again rechecked all connection and again all seemed ok so tank on hit the button the engine turned over with new battery gusto but would not fire at all now , as I said ive checked all coonections and now fuses even fitted a new fuel pump in case running it dry for a second or two may have damaged its effiency but it just will not fire now , any pointers would be very much appreciated !
 

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Unbolt the tank and raise it up so there is no pressure on the fuel lines then start it. Seems like one might be pinched
 

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Discussion Starter #3
tried that still the same , i get the feeling its fuel , ive another fuel pump i'll try in the morning
 

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A couple observations: What do you mean by 2007(ish)? Year of manufacture is important, especially when looking at wiring diagrams, for diagnostics.

How do you "know" you got all of the connections in the right location?
 

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Discussion Starter #6
Hi , I said 2007 ish because thats when it was registered but personally am not sure without checking the exact date of manufacture , to add to my tale of woe I must add that whilst continuing to crank the engine over there was no apparent smell of fuel so i'm off to check out the fuel lines now,I know i've the connections correct as I noted down the disassembly as I was doing it
 

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Look at your VIN #.... 8th character from the end indicates year model. A 2007 will be a "7" and a 2006 will be a "6", and so forth ....2010 models will be "A".... a 2000 is a "Y"

You could have a quick connector that is not opening and therefore not allowing fuel to flow. Do you have the original plastic connectors? or have you replace any of them? and if so with what?
 

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Discussion Starter #8
it;s an 07 F4R , just checked the VIN, i've in mind to check the fuel lines in the mornig when the battery's fully charged , was going to put the tank back on but dissconect the fuel lines from the rail and run the into a bottle to see if im gettinf fuel out under pressure and go from there, cheers Chris
 

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Chris, if you do that, be prepared for a fuel mess. That pump puts out 45 psi regulated.
 

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Discussion Starter #10
thanks for the warning, I was going down that route to try to prove the pump I am going to extend the hoses into a five gallon container , thanks for the warning , ill keep all informed of the situation , cheers Chris
 

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Discussion Starter #12
not aproblem , the kettles always on , i was going to loop the rail side with clear tubing so as I can see the circulation , coud even did out and attach apressure gauge to check it !
 

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Discussion Starter #13
I did , this morning lift the air box and upon turning the engine over squirt some fuel down the throttle bodies , did not get it to fire at all , not even a whimper , now that leads me to think for sure it must be an electrical fault, I decided against running the fuel rail lines into a container after carefull thought as I was pretty sure the fuel pump was ok
 

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You need to know if the the problem is fuel or spark without guessing.
Take a plug lead off and spark plug,earth the plug and crank the motor to see if you have spark,it’s not that hard.
If you have spark,then disconnect a fuel hose from the injector rail,place the hose into a small container,turn the ignition on and see if fuel squirts out.
Do those tests first to tell you what’s happening.:smile2:
 

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Discussion Starter #15
i'm sure spark is the problem Mitch , as i've said I did squirt juice into the injector bodies and not a peep out of the motor , i also changed the fuel pump for a spare that I had and no difference, every thing cycles as it always did on start up but now no fireing
 

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I did unplugged each of the coils but it didn’t help. It’s a slow process to track down the fault as I can’t locate a wiring diagram.? My bike is a 2008 F4 312R. ?
 
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