Fuel Pump

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UPDATE:

Received test kit from sean morley plus fuel pump...so lets break it down.

I havnt been able to get my vmax to run and have been trouble shooting what i can without the kit, last week i decided to bypass the fuel pump and just have fuel enter carbs via gravity, bike ran great! so hazaa!!! its the fuel pump...

Well here i am working fuel pump, i see it pump fuel to carbs via the glass fuel filter but the bike will not start...doing what it did before...but what i notice and i should have mentioned this...is i can hear a low rumble from the exhaust...but only while the start button is pressed...so ...active starter = rumble exhaust...thats why it keeps sending fuel to carbs i think..because im actually using the fuel ...just not running by itsself...so what will keep the engine firing after i stop pressing the starter?


Could this be a CDI issue?

Thanks everyone for all the help!



If the bike started and ran well, while it was being gravity fed it's fuel, the ignition system must be working properly, as well as the carburation system.
- when you "bypassed" the fuel pump, during the gravity feed, did you have the power to the pump disconnected? I'll assume that you did.
- if so, why not try unplugging the pump, hooking up your gravity feed system, starting the bike, letting it warm up a bit, then connect the pump. If the bike stalls, you have an electrical problem, maybe the fuel pump relay. The relay is tied into the ignitor(was a spare relay include with the test kit?)
Of course to try this, you will have to put the discharge line of the pump into a container, in case the bike(and pump) continues to run. Safety first!
Cheers!
 
Hey guys, ok i tried the gravity feed and it was not working either...did u get the part where while start button is engaged the engine fires..i think its such a low tone..but i put my hand in front of exhaust and sure enough i feel exhaust coming out, also, i switched out the cdi boxes and had no effect...i did all combinations, gravity feed with pump installed and not installed...there was a spare relay with the kit but that did not fix the issue...maybe its the piece of equipment the spark plug leads plug into...dont know what thats called.

Thanks a bunch guys...this baby will live again eventually but only thanks to this forum! lol..
 
Hey guys, ok i tried the gravity feed and it was not working either...did u get the part where while start button is engaged the engine fires..i think its such a low tone..but i put my hand in front of exhaust and sure enough i feel exhaust coming out, also, i switched out the cdi boxes and had no effect...i did all combinations, gravity feed with pump installed and not installed...there was a spare relay with the kit but that did not fix the issue...maybe its the piece of equipment the spark plug leads plug into...dont know what thats called.

Thanks a bunch guys...this baby will live again eventually but only thanks to this forum! lol..

Even though the bike did run once(?) on gravity feed - are you sure it's not stale gasoline in the bike's tank? Was the gravity feed gas fresh?
If you think the bike is firing only while the starter is being depressed, confirm this . The easiest way is to buy or borrow one of those testing devices than you clamp onto the spark plug wires.
If you have fire at all four plugs wires, I would try installing new plugs, if you haven't done that already. Before installing each plug, you could then check for the quality of the spark, while turning over the bike.
The only time my bike has behaved as you describe - seems to be running, but just barely, and at a low pitch - has been when I've forgotten to set the choke properly. Have you checked to make sure that your linkages have not disconnected?
 
sounds like a good plan, to test the spark plug...the wires themselves seem pretty corroded, i will need to get new leads and maybe some plugs...but if its bad plugs why would it act this way, then run...then act this way again...and confirmed...while start button is depressed exhaust comes out of pipes...so its like its running only with active spark...sometimes the engine will try and turnover but then it wont...and a huge cloud of gas puffs out of the carb air filters every so often..so like sean morley said i might also need to clean the pilots or whatever
 
sounds like a good plan, to test the spark plug...the wires themselves seem pretty corroded, i will need to get new leads and maybe some plugs...but if its bad plugs why would it act this way, then run...then act this way again...and confirmed...while start button is depressed exhaust comes out of pipes...so its like its running only with active spark...sometimes the engine will try and turnover but then it wont...and a huge cloud of gas puffs out of the carb air filters every so often..so like sean morley said i might also need to clean the pilots or whatever

Mr. Prime-
I took the time to review your threads and posts from the time you joined this forum. A few conclusions-
- you bought an old bike, from a previous owner that tinkered with it, perhaps not sure of what he was doing (such as mixing up the relay connections)
- the bike has been modified (Kerker, stage 7). This probably means the carburetors have been modified from their stock settings, and you have individual air filters
- your own understanding of the bike is limited, and you obviously don't have a service manual. By your own admission, your mechanical knowledge is limited as well. No disrespect intended here. Probably the majority of the members on this forum, included myself, joined this group because of a desire to learn more about the max, and pick up knowledge that others have acquired. All with the goal of performing as much maintenance/modification as possible, saving money, keeping trips to the dealership to a minimum. Eventually, many of the "newbies" begin to share their experiences with others, and The Circle continues. That's what makes this forum so great.
- as for your present problem(s) with your bike, and after reviewing all your threads and posts, (especially today's), my guess is that carburation is at fault, and was since you purchased the bike (you mentioned idle, surging, stalling, "no pull" conditions, then no-starts ,under both hot and cold conditions.)
The carburators on these bikes are notoriously fickle, particularly the low-speed circuits, which have a huge bearing on how well the bike starts, and idles. All this has been further complicated by the use of ethanol-containing fuels.
-in conclusion, I would suggest performing the "shotgun" cleaning technique, preferably by an experienced bike mechanic, that has worked with v-maxes. Once you've seen it done, and how relatively easy it is, you will be able to tackle it yourself, next time.
Best of luck!
 
Great post Miles. I would only add that I believe the "shotgun" and "peashooter" tutorials are good enough that most anyone with basic tools should be able to do
 
Yeah your absolutely right miles, and i do have a service manual in pdf format but havnt read into it too greatly, another thing i was thinking was sending the carbs to Sean Morley, the rebuild/cleaning for 400 is a great deal, and im sure it will solve most of my problems, considering i have very little invested in this bike, 400 would be great to get it to a good running condition.

As for what you said about coming to this forum to learn and get to know the vmax and suck up any knowledge i can, you can bet on that, but im not going to be one of those people who come on here until the bike is fixed then disappear...im going to learn everything about the vmax as i can and to do that i need to start at the basics of engines and electrical systems, the best way i can do that is to take it apart and read the forums

Ive actually learned a whole hell of a lot browsing the forums and reading stickies...the pictures and explanations make my life so much easier, im looking forward to being able to assist others in the future when they have questions and my 2 cents is actually worth a damn!

its Kind of funny you see, I am a submariner...and we go through this qualification process where you learn how every piece of equipment on the boat work, hours and hours, days and days spend in manuals understanding the basic operation of the submarine, from hydraulics to High pressure air and even the nuclear reactor...i am qualified now and i feel like im going to go through the process again with the vmax...cant wait to get my vmax pin i can wear on my chest haha!!
 
its Kind of funny you see, I am a submariner...and we go through this qualification process where you learn how every piece of equipment on the boat work, hours and hours, days and days spend in manuals understanding the basic operation of the submarine, from hydraulics to High pressure air and even the nuclear reactor...i am qualified now and i feel like im going to go through the process again with the vmax...cant wait to get my vmax pin i can wear on my chest haha!![/QUOTE]

A submariner? Impressive! First I have to say -
Thanks for your service
Knowing a bit about your background and job experiences, I'm inclined now to agree with Patmax- by all means, tackle the carb cleaning by yourself. You have nothing to loose, the costs are minimal. Perhaps the carbs eventually will have to taken off and given a complete makeover -it's an old bike, and this has probably not been done. But, you may get lucky.
Read every post about the Shotgun technique before starting. One of the most frequent problems encountered is the removal of the idle screws. If they are badly corroded, they don't come out as an assembly(o-ring, washer, spring, screw). Often the o-ring stays in the orifice, and has to be removed with a pick. If you use air pressure to remove the screws, make sure to keep a finger over the orifice to prevent the parts from flying into the great beyond. One forum member uses a drinking straw to withdraw the screws.
The "Peashooter" technique does not involve full removal of the idle screws, therefore I would suggest doing the Shotgun.
Also, before attempting to remove the screws, soak them well with WD 40 (or equivalent) The threads will strip easily, if too much pressure is applied. Your first action after they are free to move, will be to turn them clockwise until you can feel them lightly seat - at the same time counting the revolutions required. You do this to be able to return them to their original settings, following cleaning. These settings may have to be later adjusted to obtain optimum running conditions. This is when the more experienced carburater folks will help you, epecially those familiar with your carb/exhaust setup.
Best of luck, keep us posted, keep the questions coming!
And one final thought - learning the systems and operational requirements of a nuclear submarine will no doubt help you, when you tackle the maintenance of a far more complicated piece of machinery - the mighty V-Max!
Cheers
 
Thanks for your service

Your Welcome!!

So i did try the shotgun method but quickly backed out as the first carb i tried it seemed to show that the previous owner, when he laid it down, it packed the idle mixture screw hole with dirt and i am unable to get the screw out, i am afraid it is stuck a couple of turns out and the screw is now stripped...golden flakes spewed out when i sprayed some dust-off...i did let it sit in wd-40 but it didnt dent it at all..that screw is not budging at it being stripped is not helping one bit.. i also have a wife and daughter and work about 70 hours a week...so i dont have alot of time to do the carb cleaning/rebuild which im not even positive it needs...since it seemed to run fine a week ago...i did drain the float bowls and but fresh gas in gravity feed and the bike still wouldnt fully turnover...i say fully because while holding the start...i hear a rumble and exhaust comes out...this is very perplexing to me...so yeah...cleaning/rebuild may be the next step if i cant figure this issue out...of course...i could go for some new plugs...
 
UPDATE:

ALIVVVVEEE!!!!

2 Spark plugs were dead...replaced all 4, Beast is once again alive...thanks to these forums and Sean Morley, I have learned an incredible amount about this bike while taking it apart and trying to fix the little issues...

Thanks everyone!
 
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