Not a silly question, since I didn't know there was a hose between the intake and advance. I'll check it tonight with the other great suggestions.
Need Advice: first start after long neglect
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Not a silly question, since I didn't know there was a hose between the intake and advance. I'll check it tonight with the other great suggestions.
The Beekeeper
Well-Known Member
Another thing you could try is to run it without the fuel cap on the tank, could possibly be building vacuume and starving the carbs..................Tom.
Ran it without the fuel cap, even removed the new fuel filter in case that was defective. No change.
Checked the hose from the manifold to the advance: looks OK.
Opened the drain screws for the float bowls right after it quit and found plenty of fuel in all four bowls.
Couldn't keep it idling long enough to spray anything on the manifolds. They do have some hairline cracks on the exterior. But I would think they aren't enough to keep it from running at all without the choke.
I'm not sure how I would go about checking a heat-related issue with the pickup coil, but it doesn't seem to get hot enough before it quits for something like that to be an issue.
Checked the hose from the manifold to the advance: looks OK.
Opened the drain screws for the float bowls right after it quit and found plenty of fuel in all four bowls.
Couldn't keep it idling long enough to spray anything on the manifolds. They do have some hairline cracks on the exterior. But I would think they aren't enough to keep it from running at all without the choke.
I'm not sure how I would go about checking a heat-related issue with the pickup coil, but it doesn't seem to get hot enough before it quits for something like that to be an issue.
Ran it without the fuel cap, even removed the new fuel filter in case that was defective. No change.
Checked the hose from the manifold to the advance: looks OK.
Opened the drain screws for the float bowls right after it quit and found plenty of fuel in all four bowls.
Couldn't keep it idling long enough to spray anything on the manifolds. They do have some hairline cracks on the exterior. But I would think they aren't enough to keep it from running at all without the choke.
I'm not sure how I would go about checking a heat-related issue with the pickup coil, but it doesn't seem to get hot enough before it quits for something like that to be an issue.
Checked the hose from the manifold to the advance: looks OK.
Opened the drain screws for the float bowls right after it quit and found plenty of fuel in all four bowls.
Couldn't keep it idling long enough to spray anything on the manifolds. They do have some hairline cracks on the exterior. But I would think they aren't enough to keep it from running at all without the choke.
I'm not sure how I would go about checking a heat-related issue with the pickup coil, but it doesn't seem to get hot enough before it quits for something like that to be an issue.
Miles Long
Well-Known Member
Maybe not carb-related at all?????!
The ignition module needs a healthy voltage for the bike to idle properly.
Have you put a meter across the battery terminals and monitored the volts during startup? If it drops much under 12.1-.3, I'd suspect charging issues.You could then pull the headlight fuse, to lighten the load on the system, and see if that improves the idle.
Cheers!
The ignition module needs a healthy voltage for the bike to idle properly.
Have you put a meter across the battery terminals and monitored the volts during startup? If it drops much under 12.1-.3, I'd suspect charging issues.You could then pull the headlight fuse, to lighten the load on the system, and see if that improves the idle.
Cheers!
You can check with an extra spark plug and a wire from one cylinder. After the bike dies, use an external spark plug grounded to the engine to see if you've got spark. In my case, once warmed up, my spark was gone. you can also do a resistance check at the connector under the seat. on my 91, it should have read between 95 - 125 ohms @ 68 degrees. when warmed up, mine read an open circuit.
If you want to skim thru my nightmare, here's my story from the 1st forum, before I knew about this one.
http://www.starvmax.com/kunena/28-help-desk/173491-91-vmx12-question?limitstart=0
If you want to skim thru my nightmare, here's my story from the 1st forum, before I knew about this one.
http://www.starvmax.com/kunena/28-help-desk/173491-91-vmx12-question?limitstart=0
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Mine will restart after it dies, but gets harder to keep running the warmer it gets.
I'll check the resistance tomorrow - and also the battery voltage as Miles suggested.
PROGRESS! (I think)
I'm reluctant to confess my stupidity in a public forum, but it finally occurred to me to try adjusting the idle air screws. They were initially set at 2-1/2 turns out as per NaughtyG's instructions. Since the bike seemed to be running lean, I turned them in to 1-1/2. It started right up and idled much longer, allowing me to lift the choke lever almost all the way closed before it quit.
But the extra run time uncovered another problem. On one of the carbs, gas is bubbling out of the main jet air bleed, the one next to PAJ1. And when the bike finally quit, it sprayed a jet of fuel several feet in the air.
This sounds like a stuck float to me. Is there an easy way to try to free it up without removing the whole carb assembly?
I'm reluctant to confess my stupidity in a public forum, but it finally occurred to me to try adjusting the idle air screws. They were initially set at 2-1/2 turns out as per NaughtyG's instructions. Since the bike seemed to be running lean, I turned them in to 1-1/2. It started right up and idled much longer, allowing me to lift the choke lever almost all the way closed before it quit.
But the extra run time uncovered another problem. On one of the carbs, gas is bubbling out of the main jet air bleed, the one next to PAJ1. And when the bike finally quit, it sprayed a jet of fuel several feet in the air.
This sounds like a stuck float to me. Is there an easy way to try to free it up without removing the whole carb assembly?
PROGRESS! (I think)
I'm reluctant to confess my stupidity in a public forum, but it finally occurred to me to try adjusting the idle air screws. They were initially set at 2-1/2 turns out as per NaughtyG's instructions. Since the bike seemed to be running lean, I turned them in to 1-1/2. It started right up and idled much longer, allowing me to lift the choke lever almost all the way closed before it quit.
But the extra run time uncovered another problem. On one of the carbs, gas is bubbling out of the main jet air bleed, the one next to PAJ1. And when the bike finally quit, it sprayed a jet of fuel several feet in the air.
This sounds like a stuck float to me. Is there an easy way to try to free it up without removing the whole carb assembly?
I'm reluctant to confess my stupidity in a public forum, but it finally occurred to me to try adjusting the idle air screws. They were initially set at 2-1/2 turns out as per NaughtyG's instructions. Since the bike seemed to be running lean, I turned them in to 1-1/2. It started right up and idled much longer, allowing me to lift the choke lever almost all the way closed before it quit.
But the extra run time uncovered another problem. On one of the carbs, gas is bubbling out of the main jet air bleed, the one next to PAJ1. And when the bike finally quit, it sprayed a jet of fuel several feet in the air.
This sounds like a stuck float to me. Is there an easy way to try to free it up without removing the whole carb assembly?
The time honored method is to use a long bladed screwdriver or a long socket extension, and to 'rap' it against the float bowl to dislodge any residual sediment that may be keeping the float needle from seating. Success is realized when the 'gushing' stops.
No amount of tapping has any affect. So I guess it's all coming back apart again.
Any advice on what to look for to make sure it doesn't have to be done a third time?
I've already cleaned the carbs thoroughly multiple times, installed new float needles, set all float levels as per NaughtyG's tutorial, replaced the fuel lines, and installed an additional sintered bronze fuel filter between the fuel pump and the carbs [all before turning on the key for the first time]. No contamination shows up in the new fuel filter, and I don't see how anything could have been introduced in the three or four inches of new fuel line between the filter and the float bowls.
I've been experimenting some more and things are getting even more confusing. What I thought was a stuck float appears to be something else. I removed the fuel line from the offending carb and blew into it, only to find that the float needle appears to be seating OK.
I put the fuel line back on, then turned on the key and looked down inside with a flashlight. I can hear the pump run for a second or two, but everything looks OK. Then when I start the bike, fuel appears to start leaking around the jet needle. But if I open the piston manually while its running (without opening the throttle valve), the leak stops. As the bike continues to run, I can see fuel creeping up the main jet air bleed, next to PAJ1. If I turn off the key, fuel sprays out of the main jet air bleed several feet in the air. If I allow the bike to continue to run, fuel eventually reaches the top of the main jet air bleed and starts to overflow into the throat. The bike then starts to smoke out of the offending cylinder, I can hear that cylinder start to foul, and ultimately cut out completely.
An unrelated observation: while all of this is happening, on a different carb, smoke is pouring out of the hole which is adjacent to, and counterclockwise from the main jet air bleed hole. The smoke continues for several minutes after I shut off the engine.
I put the fuel line back on, then turned on the key and looked down inside with a flashlight. I can hear the pump run for a second or two, but everything looks OK. Then when I start the bike, fuel appears to start leaking around the jet needle. But if I open the piston manually while its running (without opening the throttle valve), the leak stops. As the bike continues to run, I can see fuel creeping up the main jet air bleed, next to PAJ1. If I turn off the key, fuel sprays out of the main jet air bleed several feet in the air. If I allow the bike to continue to run, fuel eventually reaches the top of the main jet air bleed and starts to overflow into the throat. The bike then starts to smoke out of the offending cylinder, I can hear that cylinder start to foul, and ultimately cut out completely.
An unrelated observation: while all of this is happening, on a different carb, smoke is pouring out of the hole which is adjacent to, and counterclockwise from the main jet air bleed hole. The smoke continues for several minutes after I shut off the engine.
blaxmax
Well-Known Member
Have you had the carbs back off since #9 of this thread to check and see if you put it all back in the correct order? Try going through this one below.
http://www.vmaxforum.net/showthread.php?t=5830
http://www.vmaxforum.net/showthread.php?t=5830
That's the procedure I followed. I haven't taken them back off ... I was hoping to avoid that. I was very careful about putting them back correctly. I did one at a time. It seemed pretty straightforward and I'm not sure what I could have messed up and still have them go back together.
But that may have to be the next step. I just wish I had some idea what to look for.
sdt354
Well-Known Member
Quick float level check. Put the bike on the center stand, or level somehow. Cycle the fuel pump. Get a small glass jar and drain each carb into the jar. Make sure the drain hoses are clear. Compare the volumes with cylinders that appear to be functioning well. I think you'll find much more fuel coming from one carb, or more. If you have to open the carbs, make sure the needles are on the float tang properly. Set the level again, do a final wet check of the float levels. I like to break the carb rack down in halves, then do a wet check/adjustment while I have carb bowl/float access. This will require a little fuel bottle set-up, or you can do it on the manifolds and use the fuel pump to fill the carbs.
davesax36
Well-Known Member
I'm back in with, and could come on Thursday to help out if you want. Not that you won't get it before then...
Looks like sdt354 called it. I drained the bowls as he suggested. Got approximately 30 cc from three of the carbs and 38 from the problem one. So I guess I'll be taking them back off to see if I can find the problem.
I probably wont get to it before Thursday, so no point in coming down. I really appreciate the offer, though. I'll keep you posted on the outcome.
I'm sure many of the members that have replied know what they are talking about and their advice should help you fix your issue.
I had the same issue with my Gen 1's every spring it seems that the carbs were all messed up. after many people tried to help me I couldn't get them fixed no matter how much advice I got ( very good advice from very knowledgeable members) I gave up and shipped my carbs to Sean and he did what he does and when I got them back it started up and ran like a charm.
I had the same issue with my Gen 1's every spring it seems that the carbs were all messed up. after many people tried to help me I couldn't get them fixed no matter how much advice I got ( very good advice from very knowledgeable members) I gave up and shipped my carbs to Sean and he did what he does and when I got them back it started up and ran like a charm.
blaxmax
Well-Known Member
You need to set the float levels.
I set the float levels when I rebuilt the carbs, as evidenced by the fact that three of the bowls held exactly the same amount of fuel. I suspect the problem may be that something came loose as I buttoned it back up. But I guess I'll find out.
