Changed plugs, bike starts but stops immediatel..... need advice from the gurus plz

chuck.cbr99 · 09-10-2007, 8:46 AM

Hi guys, So this weekend, I changed my spark plugs and oil. My bike turns over but won't start continuously....Couple of times it started but stopped in about 2 secs....

I checked the fuel hose from the fuel pump to the carb. When I turn the ignition key, there is a small surge of fuel from the hose going to the carb for about 1 sec and then it stops..Is this normal? Or should there be a continuous flow of fuel at that point?

Also I used cheap fuel and not premium. Could that be a problem (read: contaminated fuel)?

HCCAFan · 09-10-2007, 2:25 PM

"Not premium" fuel would actually start easier than premium fuel so long as it wasn't half water. I don't know what bike you have but is it possible you out the plug wires on in the wrong order? What did you gap the plugs at? What did you have to remove to get to the plugs? Are you sure the plug wires are seated? Did you replace the plugs with something besides what was in there?

chuck.cbr99 · 09-10-2007, 3:07 PM

I have a 99 CBR F4. The plug wires are properly seated and in the right order. I removed the coils and pulled the plugs out and put new ones in. I replaced them with the same type that was in there before.

When I turn the ignition key and push the start button, the hose that's connected to the carb bridge sees fuel come out for 1/2 sec, then it stops. There is no continuous flow even when no pressure is applied. Is that normal? Does the fuel pump on a 99 CBR continuously pump fuel?

If thats the case,

1) Either the fuel pump is bad
2) Or the fuel relay is bad and makes contact for that 1/2 sec and then disconnects.
3) Or the ECU system is screwed up
4) Ignition switch problems??? (I Hope not !!!!)

I am going to try and connect 12V directly to the pump and see if it whirrrrs up continuously. If so then maybe its the wiring/relay upstream.

Let me know what you guys think. THanks in advance.

HCCAFan · 09-11-2007, 2:25 PM

The easiest thing I can think of is pulling the plugs out and see if they are sparking or not when you crank it. I don't know about the fuel pulse thing but it doesn't need to be dumping a ton of fuel and it knows it, especially if it's not running.

tmac · 09-16-2007, 1:23 PM

check you havent "pinched" any of the breather pipes coming off the tank!

its easy done!

Charles486 · 09-16-2007, 4:55 PM

put power to the pump and make sure its not bad, sounds like a vacuum hose too, i had an f4 that i missed a vacuum hose on and it took me a week to figure it out.

chuck.cbr99 · 10-04-2007, 3:33 PM

Finally got it running....guess what...The battery (-) connection was loose !!! Got that tightened and she is running now.....seems funny when I stop and think about how I was splitting my hair 3 weeks back.....oh well....

HCCAFan · 10-04-2007, 3:41 PM

Quote:

Originally Posted by chuck.cbr99

Finally got it running....guess what...The battery (-) connection was loose !!! Got that tightened and she is running now.....seems funny when I stop and think about how I was splitting my hair 3 weeks back.....oh well....

Hey, at least it wasn't because it was out of gas.

chuck.cbr99 · 10-04-2007, 4:35 PM

You won't believe how many people suggested that first ! Seems like a very common problem