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Discussion Starter #1
ok so i bought this 93 vulcan about 4 months ago, previous owner had to start the bike using ether, and i immediately took it to the shop to have it checked out, the shop proceeded to rape me and fed me a whole line of crud. long story short, im still having to use ether to start the bike, and the battery seems to lose its charge really fast, this is my first bike and i absolutely love it so im not even considering getting rid of it, i changed out the carb holders (intakes?) and put a new acid based battery in it, am also considering a maintenance free battery in the hopes that this will fix the elecrical problem, but every time i shoot that starting fluid in the bike i cringe, any ideas out there? its a great riding bike and runs like a scalded dog once i get it started, but it wont idle at all.
 

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HAWK
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2,576 Posts
Where are you located, there may be people close that can help.
I would check the Stator and R/R to make sure the batt is getting charged.
Try Sea Foam to help clean the carbs and fuel lines, rember there is a vacume operated petcock to allow fuel to flow.
You may have teh 3 lines mixed up, has happend before.
 

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The Professor
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Definately try the seafoam first, are you using the choke when trying to start. Sadly it sounds like your Stator or R/R is toast. Do you have a meter to check voltage while running? :beerchug:
 

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and the Adventure Cycle
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6,141 Posts
Did the new battery help at all? (definately get a maintenance free, it does make a differance)

Does the battery take a charge once you are riding the bike?

IMO, if it runs great once it's started, I wouldn't think it's a fried stator.

What all did the shop do to it?
 

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On His Lady Vulcan
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Welcome to the forum, your new home away from home. Like stated above, first priority is getting a MF Battery then use a meter to insure that youre charging system is operating properly and then I would dump a FULL can of SeaFoam into your fully filled tank and run it till she's bone dry (you dont have to do it all at once) Once you got her started whats your idle set at and does it require ether even after shes been running a while and all warmed up or does she fire right back up after you shut her down? Let us know what you come up with, theres over 5k members here that are willing and wanting to help make this bike a dream for you so dont hold back. Like they say "The only dumb question is the question not asked"

Peace :beerchug:
 

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Premium Member
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Hey Clambake, before you get too carried away here I'd look at some basic stuff. Like said before me, Seafoam the full tank of gas, maybe a half a can, and let it run through the bike for a good ride then let it sit overnight. Might take a few days to make a difference but it most certainly will make a difference if there is crud in the tank or carbs. I would also see that your idle circuit is not shut off by turning the idle thumb screw on the left side of the bike to see if you can get the bike to idle. I can't remember off hand which direction increases idle, but hopefully someone will pipe in here and tell us. If not, I'll be on the bike in a little bit and will come back and tell ya.
Definitely get yourself a MF battery. I just ordered a BigCrank as my MF is over 3 yrs old and is getting weak. Plus, I would take some sand paper and clean all your points of contact that you can find in the electrical system, battery terminals, grounds etc. and then use dielectric grease on all of them and make sure they are tight. A little corrosion on a connection can go a long way to make your charging system act like it's sick. Once you have cleaned up all the connections you can find, then with a freshly charged battery (hopefully you have a battery tender) check the voltage on the battery and make sure it's at least 12.5 volts, then check the voltage when the engine is running and you should see the volts rise when you rev the bike. If you don't see this, you will have to dig deeper into the charging system, the RR and Stator. But start with the simple stuff, clean connections etc. and see what you find. Good luck!
 

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and the Adventure Cycle
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I would also see that your idle circuit is not shut off by turning the idle thumb screw on the left side of the bike to see if you can get the bike to idle. I can't remember off hand which direction increases idle, but hopefully someone will pipe in here and tell us.
Clockwise increases idle, counterclockwise decreases it.
 

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carbon unit
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If it isn't a dirty /gummy fuel situation then
it could be he's trying to run it without the breather ears. I imagine this would
cause a lean situation, assuming the mixture screws are in the stock position and or it hasn't been re-jeted
 

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and the Adventure Cycle
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If it isn't a dirty /gummy fuel situation then
it could be he's trying to run it without the breather ears. I imagine this would
cause a lean situation, assuming the mixture screws are in the stock position and or it hasn't been re-jeted
Except.... he says it runs really good once it starts.
I ran my bike with just the covers off the ears, and wouldn't get any power over 4K rpm's, but it started just fine..
 

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carbon unit
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Except.... he says it runs really good once it starts.
I ran my bike with just the covers off the ears, and wouldn't get any power over 4K rpm's, but it started just fine..
good point, I missed the part about it running ok after it starting.
....I've never tried to run mine without the ears.

my guess then, is the idle jets are clogged. Or the curb idle needs to be adjusted.
 

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Discussion Starter #11
yeah once its been running for a while it will start right up, have tried to adjust the idler on the left side of the bike, to no avail, also there is still a leak in my petcock, paid a shop to fix it but they charged me for doing it and it started leaking again as soon as i got it back, could it possibly be a vacum issue? as i said the bike runs great once it is started, and it seems to me like its not getting enough gas at starting or maybe not enough spark? im new at this and i thank you all so much its nice to finally find a group of people willing to help someone, am going to get the sea foam right now maybe that will help, will let u know. thanx again!
 

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Premium Member
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If your petcock is still leaking, it could be a lean condition (too little fuel or too much air) which could be a combination with a vacuum leak. Fuel starvation and vacuum leaks both create lean running conditions.
Weak spark, caused by weak battery (wet cell batteries tend to be weaker than sealed MF batteries) or any corrosion at any connector, will tend to act like a rich condition especially when trying to start the bike. It could also be clogged idle circuitry which might be hard to get cleared up on its own, even using seafoam.
When and how is the petcock leaking, all the time, or only when the bike is running? Where, if you can tell, is the leak coming from?
Also, what makes you believe you have or might have a vacuum leak?
 

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At this point, I think the plugs should be checked also.
 

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Discussion Starter #14
plugs are new, i changed them recently, petcock is leaking all the time, i have to turn the fuel off to stop it, leaks from the petcock itself, not sure where on it but thats for sure where its coming from. as for the vacum leak it was just a shot in the dark, i figured since there is a vacume line going to the petcock maybe the leak is causing a vacum leak as well. also, i have been putting the starting fluid directly into the carbs on both sides when i start it so i keep the hoses from the air filters off so i can have access to the carbs in order to start the bike, i have tried to hook them up and start it but it wont work, how do i check the idle circuitry?
 

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Premium Member
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Your petcock might be passing fuel right through the vacuum port, which would cause the engine to be running way rich at idle speed. Do you see any black smoke when you start it up? Does your exhaust smell gassy?

Sounds like you need to replace or rebuild your petcock for starters. You should wait a few days while the seafoam soaks in your carbs before looking to get into the carbs. Someone here surely will chime in on how to clean the idle circuit eventually. I've never been in the carbs on the VN750.
 

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The Professor
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If your petcock is leaking at the diaphram gasket you may just need to tighten the 4 screws, or it could be the plunger o-ring. I am repairing another members scoot and and the place he took it to originaly rebuilt the petcock but it leaked. I retightend the screws and no more leak. If it is leaking at the valve switch it is a different o-ring. If you remove the vacuum hose and fuel comes out the diaphram has a hole. If you remove the fuel lines and turn the petcock to on and fuel comes out it is the diaphram plunger o-ring or a weak/bad spring.

Since your scoot will start with ether that basicaly means your starter circuit is not working. When you open the choke it opens a plunger on the carb to allow more fuel to flow to start the engine. The starter jets could be clogged, the plungers could be stuck, or the choke cable could be disconected or broke. If you look at the left carb above the vacuum port you will see a plunger and lever. Move the choke lever back an forth to see if the plunger moves up and down, check both sides. If they move up and down the starter jet is probably clogged. The carbs will need to be disassembled and properly cleaned if the seafoam does not do the trick.

If the scoot will not idle after you get it started and the engine has warmed up the idle/pilot jet is probably clogged. The carbs will need to be properly cleaned.
 

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Discussion Starter #17
choke is working fine, put sea foam in the tank this afternoon and rode for around 30 min, letting it sit overnight and will see what happens, it did seem to idle a lil better already but it could just be my imagination, will also check the petcock to see if i can tighten it in the morning, getting my battery saturday, will let u know the outcome, thanx to everyone.
 

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Charging voltage at 2500 rpm should be close to 14 volts.
M/f battery is ok if you are not the mechanic type, however they loose electrolye and you cannot top them off like a regular battery.
I prefer the standard type myself, but i must check level on a monthly basis, especially in the summer, i replace every 4 years or so, they run approx $50.00
Regular may last much longer if you maintain, if you do not, the M/F will outlast.
The choice ultimatly is yours.
 

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Discussion Starter #19
ok got the mf battery today am charging it up, rode appx 200 miles yesterday using a half a can of sea foam per fill up, seemed to make a lil bit of a difference, but bike still needs starting fluid to start and wont idle, although it does seem to idle a lil better than before, am going to look at my manual and check on cleaning/replacing the jets.
 

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Addicted to Projects
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If you haven't had the pleasure yet, get ready for the fun of pulling and replacing the carbs. It goes to prove the designers weren't the mechanics who worked on the machines. To answer two questions that are sure to run through your mind during the process: They really do come out and yes they do have to go back in.
 
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