running lean

[jlabster]

My bike is a daily driver, or at least it was. This is a 2004 vs1400 almost stock with 25,000 miles. I have had it for 2 years and bought it with 10,000 miles on her. The routes I take to work are all highway speeds. It started to die coming to stop lights or when I got off the throttle. I noticed the pipes turning gold color which means she is starving for fuel. I went straight to the fuel pump and relay. I checked the relay and it was a bit off of the ohm's it was calling for, so I replaced it. I checked the fuel pump and it seems fine. I checked the air filters, which were replaced in the winter, they were a tad dirty, but not bad. I thought maybe there was stuff in the drain lines from the air filters so I blew them out with air and there was some junk in them but again not bad. I fired her up in the garage and after she got warm, I can't get on the throttle off idle hard or she dies. At higher rpm she sounds fine, but then loses power and dies. So last night I pulled the plugs, the front one was blackish, the back one redish. This tells me the front plug either wasn't firing correctly or i was running rich. I bought new plugs to ensure the plug wasn't fouled. They were due anyway. I also checked the battery and sure the cables were tight, checked all connections that I could see even under the seat and made sure they were tight and removed the fuel filter that I had installed. She starts and seem to run fine until she got warm. The same thing, she is dies on throttle engagement, and at steady higher rpm she dies. As I was climbing around the bike looking for things that are loose, and such, I noticed that the right side of the bike, or front cylinder was not very hot. I touched the pipe and it was only slightly warm whereas the rear cylinder is scalding hot! ah-ha, now we are getting somewhere... I started the bike back up and the exhaust coming from the front cylinder is cold almost! I tested the spark going to the cylinders, and they are nice and blue. So, back to the fuel. I am thinking of doing a carb sinc, but was wondering if I am missing something else? I really love this bike, and like I said she is my daily driver. Thanks for any help.

[DMIntruder]

As I suggested in your other post, I would check the fuel volumes in both float bowls. If nothing else just for sanity sake. make sure you are getting the proper fuel to the carbs, this will tell you that. Only then would I dig into the carbs themselves.

The cold front cylinder would seem to suggest more of an ignition issue though. An electrical check of the ignition system components would be good to do before pulling carbs too. Try a sync also before you pull the carbs. You want pulling the carbs to be the LAST thing you do, IMO.

If you have to go that route, pulling the carbs, do it the right way. Completely remove them, disassemble, clean, reassemble, sync, and run.

[YoDude]

I assume you've checked it but just in case you may have forgotten to, check the the petcock under the tank to be sure the screw driver slot is pointing vertical and not sideways. From your description, it sounds as though this wouldn't be your problem, but sometimes the simple things can bite you in the butt.

Yo-

[jlabster]

I started at the front carb, removed the fuel line to it, started the bike, no fuel!!! wha-laa... now I found something. So I go back to the pump. I turn off the gas, pull the pump and grab my little gas tank and a bucket. When I crank the bike fuel shoots out, but not near as much as I expected. When the bike started (there is still fuel in the carb) I let go of the starter and the pump stopped. That doesn't seem right to me. Time to check the manual but I am pretty sure the pump is shot. I had done the ohms test on the pump before but never checked the actual pressure. Any thoughts or should I just get a new pump?

[jlabster]

So I did the test in the manual. I put a line onto the inlet side of the fuel pump, put it into my gas tank put the negative onto the black wire, and positive into the Brown wire. Nothing happened. There is twelve volts there, I double checked. So then i took it to my boat battery which is charged and still nothing at the pump. That doesn't make sense. I took it back to the bike connected it back up and when I hit the starter it pumps, not a lot, but it pumps. What am I missing here? when the bike starts the pump still turns off too. I just replaced the relay too.

[YoDude]

I'm not exactly sure about your procedure about how you tried to test the pump. There's a spec in the book that states how much fuel is supposed to be delivered over a certain period of time. I'd have to look it up to give you and answer on that. The way the fuel system works when it's all working properly is like this:

When you hit the starter button, the fuel pump operates. If you let go it'll stop. That's normal operation for the fuel pump, UNLESS the engine it running. Once the engine starts running, a signal is sent to the fuel pump relay that senses that and it says, "Ah Ha! the motor is on" and so it keeps the fuel pump working as long as that is true. If the bike dies out for some reason, the fuel pump relay doesn't get that signal and shuts off the fuel pump.

Does this help you?

Yo-

[DMIntruder]

When I tested the fuel pump on my 97 I completely removed it from the bike. Then using a 1 gallon can of Kerosene, recommended in the service manual to use, I connected my portable 12VDC battery jump start box to it. The thing pumped like a SOB. My catch container was very full in no time. I did this several times and it worked/pumped each time.

If you are applying 12+VDC directly to the pump, completely disconnected from the bikes relays and it does run, then your pump is bad.

[jlabster]

According to the manual, if you apply 12 volts to the pump, it will run, which makes sense. It is just a two wire input, hot and ground. When I run the pump on the relay, it does come on. What is so special about the relay that makes it work but not with 12v straight?

I replaced the relay last week, because the resistance was off slightly when I did the ohms check. Yes, I have the one the book calls for.

I understand the relay should put power to the pump when cranking, but then it should switch (relay) the power to the run side, which it does not appear to be doing.

My thought is the pump is bad because it is not working with 12v applied. But it doesn't make since that it pumps with the relay engages, that is what is confusing. I will look at the schematics today and trace this back as far as I can.

Any help would be appreciated.

[jlabster]

Sorry Dm Intruder, your post came through as I was typing. Yes, I agree the pump is probably bad. I just don't understand why it still pumps when connected to the relay. I just wonder if there isn't another problem in there.

[jlabster]

I also wonder if they didn't change something with the pump or relay since the manual covers all these different years as well.

[DMIntruder]

You would have to dig into the wiring diagram to see how the relay is connected. I am sure it is a basic logic gate, something like: Ignition switch on AND clutch lever pulled in AND 12VDC present, etc.

That is why I completely removed it from the bike to test mine. That way you are testing only the pump and nothing else. Simple process of elimination.

[DMIntruder]

I also wonder if they didn't change something with the pump or relay since the manual covers all these different years as well.

The key is to ensure you get the EXACT wiring diagram for your bike. Some things changed over the years, mostly minor, but still could be enough to trip you up. I know as time when on different switches were added to the handlebars; those change the Logic of the circuit as referenced above.

[jlabster]

I did remove it from the bike but now I am wondering if there is something up with the connections I made. The darn thing should pump if 12volts are applied. There should be no reason it doesn't. I will test that theory tonight after work.

[jlabster]

okay, I think I found out why it is only pumping on start up and not when hooked up on a 12v battery. After looking over the wiring diagram, I realized that the relay receives its power from starter switch. Now, that wire O/W is the same wire that powers both coils and comes from the ignitor. Just like in most vehicles, when you hit the starter, everything else shuts off, giving more juice to the battery and components needed to start. (usually higher amp and voltage). The higher amp and voltage is enough to push through the fuel pump and getting working. When I connected the fuel pump to the 12v battery it was not enough to get it pumping, but I am willing to bet that if I take that pump over to a car that is running or something pushing higher voltage that 12v, it will work! Bad coils inside the pump is what I am willing to bet... Will find out tonight for sure. Will repost this evening and let you all know.

[jlabster]

I kind of figured it was bad, but it didn't make sense to me why, until now. I guess I still have that little man in me that likes to know the reason why. Next thing you know, I will be trying to figure out why I can't burn the rear tire off this thing!!!