Hello!
First time posting on the forums. I have a Vision a family member gave to me that's been sitting for quite sometime.
I originally got it to start for about 10 seconds before I rebuilt it with some starter fluid but I never could after that and said screw it I'll rebuild it.
Today I got it back together and back on but to no surprise I didn't do much but turn over.
There is a spark along with correct voltage and new plugs.
I pulled the plugs and it seems to be dry and theres no smell of gas.
The bowls in the carb are filled.
A few questions.
The connector in the photo did break recently so im not sure if this is detrimental? Does anyone have a carb for parts I can purchase?
I know people have mentioned removing the fuel pump and it working or perhaps installing a small 12v fuel pump?
NOTE: THIS IS NOT MY CARB!
(http://i.imgur.com/t0ayzNA.png)
Thank you!
Cheers!
If there is fuel in the float bowls, fuel supply is probably not your problem. Vs' absolutely demand surgically clean carbs inside and out. Also, they demand an excellent charging system. Study the manuals that are available on this sight and learn what it takes to get V carbs clean. Don't waste your time or $ until the carbs are sterile. That is your base starting point in resurrecting your V. We are here to help. Good luck.
"NOTE: THIS IS NOT MY CARB!". . . . . .good thing that's not yours. I hope your carb set up is significantly cleaner.
It sounds like a passage or two are plugged. Since it has been sitting for a prolonged time I suggest the old fuel has become 'varnish' or worse, and must be removed. Be aware that there are some parts (O-rings, throttle shaft seals, gaskets, etc.) within the carburetors that can be damaged by strong solvents. Access to an air compressor can be very helpful for clearing passages.
Ba aware that if battery voltage falls below 10.5V the transistor ignition will not fire.
QuoteThe connector in the photo did break recently so im not sure if this is detrimental?
Not necessarily. The fitting in question leads to the regulator portion of the fuel pump. The associated pump regulator fitting is labeled an "air pipe" in the repair manual. It appears to vent the spring side of the regulator to atmosphere by virtue of the carb fitting which leads to the bowl which in turn is vented to atmosphere. This path may lessen the likelihood of debris migrating into the air pipe. Another possible reason for this connection scheme is in the event of a regulator diaphragm failure. Fuel that leaks through a tear would pass safely to the carb bowl.
In short, I tend to doubt the broken fitting is directly contributing to your no start problem.
Quote from: Br4zzz on December 08, 2016, 07:45:09 PM
I pulled the plugs and it seems to be dry and theres no smell of gas.
The bowls in the carb are filled.
There's only one way fuel will get in to a non running engine, and that's through the accelerator pump.
Take off the air box and twist the throttle. Two jets of fuel should come out the brass pipes.
If not, you can take the top off the carbs while in place, take off the brass pipes and clean them out. Watch out for the loose bits inside.
Thanks! Yes my carb is way cleaner than this thing. This one looks like it's sat at the bottom of a lake for too long.
Good to know that fitting is mostly used for venting purposes.
I cleaned out all the jets and the small brass pipe in the middle of the barrel. Everything seems clear with the air compressor. I'll take a look this weekend at the accelerator pump and see if twisting the throttle squirts fuel in.
Finally got the bike back into my garage after moving. It looks like I have two jets of fuel coming in now after I redipped my carbs for the second time!
She sounds like she really wants to start but still no luck. I have replaced the spark plugs about 8 months ago when I started working on her and I seem to be getting a spark. Any thoughts on what else I could look into?
Im guessing if the coil pack goes out then I would be getting no spark what so ever? Should I change the plug wires?
Thank you in advance!
Cheers!
Try starting with a shot of Starter Fluid down each carb throat, no choke, no throttle. If its got spark, it should run for a short period of time, therefore confirming spark and indicating a carb issue.
Quote from: QBS on April 20, 2017, 02:42:28 PM
Try starting with a shot of Starter Fluid down each carb throat, no choke, no throttle. If its got spark, it should run for a short period of time, therefore confirming spark and indicating a carb issue.
I have tried that a few times with different settings which leads me to believe it might be a weak spark issue or something of that nature?
Check your battery volts while cranking. Anything less than 10.6 volts will not fire the ignition but the starter will turn it over very well.
Quote from: Walt_M. on April 20, 2017, 04:03:10 PM
Check your battery volts while cranking. Anything less than 10.6 volts will not fire the ignition but the starter will turn it over very well.
But would it cause a spark? If I hold the plug to the frame I see a blue spark. Ill check the volts tonight.
Cranking without the plugs in is easier and requires less voltage, so you may have a spark with them out and none when installed. It is also harder to spark under pressure such as compression. Do the cranking voltage test as mentioned. You may need a new battery or a starter rebuild or both. Also make sure all large cable connections are clean and shiny.
Quote from: jefferson on April 20, 2017, 06:25:57 PM
Cranking without the plugs in is easier and requires less voltage, so you may have a spark with them out and none when installed. It is also harder to spark under pressure such as compression.
Building on that you might try one of those inline spark testers. They're relatively inexpensive - $5 at Harbor Freight, $9 at Auto Zone.
If it has good spark under compression we'll have to assume for the moment it's sparking at the right time too. That leaves 2 of the 3 basics - correct fuel mixture and adequate compression. Since the correct fuel mixture is in question and difficult to test, I'd check compression. You can get a loaner from AZ for free.
If spark or compression fail, follow up with the offending (or both) item. When they both pass, move on to the carbs.
As Walt pointed out there is also the issue of cranking speed and voltage. I think you mentioned having rebuilt the starter so make sure you have a "good" battery. What constitutes a good battery could probably fill a separate post. If the bike has been sitting for some years, the battery is probably not good - even if you charge it. You may not want to invest in a new battery before knowing if the bike is viable but without a good battery much of the diagnostic work becomes suspect.
The first start is always the hardest.
You can eliminate battery issues for the time being by using jumper cables off a car battery
Quote from: Rikugun on April 21, 2017, 10:03:20 AM
Quote from: jefferson on April 20, 2017, 06:25:57 PM
Cranking without the plugs in is easier and requires less voltage, so you may have a spark with them out and none when installed. It is also harder to spark under pressure such as compression.
Building on that you might try one of those inline spark testers. They're relatively inexpensive - $5 at Harbor Freight, $9 at Auto Zone.
If it has good spark under compression we'll have to assume for the moment it's sparking at the right time too. That leaves 2 of the 3 basics - correct fuel mixture and adequate compression. Since the correct fuel mixture is in question and difficult to test, I'd check compression. You can get a loaner from AZ for free.
If spark or compression fail, follow up with the offending (or both) item. When they both pass, move on to the carbs.
As Walt pointed out there is also the issue of cranking speed and voltage. I think you mentioned having rebuilt the starter so make sure you have a "good" battery. What constitutes a good battery could probably fill a separate post. If the bike has been sitting for some years, the battery is probably not good - even if you charge it. You may not want to invest in a new battery before knowing if the bike is viable but without a good battery much of the diagnostic work becomes suspect.
Thanks for the reply! Ill give those all a try and see where it takes me.
As for the battery its fairly new, I purchased it around October last year so I would imagine its in decent condition.
Batteries discharge while sitting on a shelf, every day a little bit. The battery must be charged to near capacity or you risk under performance.
Alright, I replaiced the coil packs and wiring as a preventative measure. I hooked the bike up to my car battery and gave it a go. It's so close to starting. Running the starter it would almost get going but wouldn't quite catch. Like a very very low idle in which the starter had to keep the revolutions going.
Battery is charged up. Fairly new plugs. Coils. I'm guessing to look back into the carbs?
Sounds like starter circuit issues. The jets could be plugged or the actuators are not opening. Will it start if you twist the throttle to actuate the accelerator pump?
Quote from: Walt_M. on April 28, 2017, 05:17:00 PM
Sounds like starter circuit issues. The jets could be plugged or the actuators are not opening.
Not a bad place to look when having cold start issues. The enrichening (choke) circuit picks up fuel via a brass tube in the carb top. Any holes in that tube must be clear. The tube sits in a well cast into the carb body noted with a red arrow. With a good flashlight you may be able to make out a small orifice at the bottom of that well. It's not uncommon for that orifice to be clogged.
I've seen quoted on this site a .010" diameter wire should be able to pass through but I've had a .060" wire pass through a carb set I have. I'm not sure what the actual size should be but this hopefully can be used as a guide.
Not choke related but worth noting is the emulsion tubes. Due to the difficulty in removing them they are often ignored or overlooked when cleaning the carbs. They can get crudded up and will have an adverse effect of fueling. Location within the carb noted with the blue arrow and tubes pictured separately. There are 2 different shapes that I'm aware of but they do the same thing.
I was hoping the emulsion tubes were dirty so I could blame something but both are all clear! It really sounds like it wants to start but it just doesn't quite catch. New battery connected to a car battery. Im replacing the plugs tomorrow perhaps they fouled at some point sitting or attempting to get running in the past few months? Ill be running a compression test as well. Im slightly at a loss now. I get some back fire on the carbs when trying out of both cylinders occasionally so I know its firing to some degree. The circuits on the back of the CDI look like new but..? I'm all out of ideas. All jets have been replaced in the carbs. Every thing has been soaked multiple times.
(http://i.imgur.com/nBwOHxC.jpg?2)
Quote from: Walt_M. on April 28, 2017, 05:17:00 PM
Sounds like starter circuit issues. The jets could be plugged or the actuators are not opening. Will it start if you twist the throttle to actuate the accelerator pump?
Actuators are opening, it fires a bit more when I twist the throttle. Im guessing since its squirting fuel from the accelerator pump. I pulled out each nozzle from the carb cleaned em up and re soldered them together. All jets have been replaced, one side behind a bolt next to the bowl overflow nozzle was missing a jet? I added one, still no luck on starting.
Since your original question was regarding the carbs I've been a bit focused on them to the exclusion of everything else. Your comment regarding a compression test is a good one as is questioning the TCI. Do you have spark under compression on both cylinders?
Getting back to the compression question....even great compression won't cure vacuum leaks. Rather than the engine breathing through the carbs it may be sourcing it's air elsewhere. There is the possibility the intake manifolds aren't sealing or perhaps the YICS is leaking or both. If you haven't already, I'd suggest plugging the engine's YICS connections for test purposes and maybe spray some starting fluid (or the like) around the manifolds while cranking the engine over and see what effect that has.
Quote from: Rikugun on May 03, 2017, 09:06:46 AM
Since your original question was regarding the carbs I've been a bit focused on them to the exclusion of everything else. Your comment regarding a compression test is a good one as is questioning the TCI. Do you have spark under compression on both cylinders?
Getting back to the compression question....even great compression won't cure vacuum leaks. Rather than the engine breathing through the carbs it may be sourcing it's air elsewhere. There is the possibility the intake manifolds aren't sealing or perhaps the YICS is leaking or both. If you haven't already, I'd suggest plugging the engine's YICS connections for test purposes and maybe spray some starting fluid (or the like) around the manifolds while cranking the engine over and see what effect that has.
I'd imagine I get spark under compression due to it firing but perhaps not effectively? Whats the best way to check spark under compression? I do get smoke out of the exhausts and carbs so it is firing to some degree. I'll block off YICS and check for any other leaks! Thanks!
I use a 12 volt powered inductive pickup timing light but not many people seem to have them anymore. I've also suggested those inexpensive inline spark testers but have little experience using them.
There are more elaborate testers whereby one can adjust a gap the spark has to jump. You can mimic the effect by sacrificing a known good plug and bending the ground electrode out straight. This test is done with the plug laying on the cylinder head, not installed. The thinking is if the spark will jump a 1/4" gap outside the engine, it's likely to jump a .028" gap under compression.
Quote from: Rikugun on May 03, 2017, 10:16:15 AM
I use a 12 volt powered inductive pickup timing light but not many people seem to have them anymore. I've also suggested those inexpensive inline spark testers but have little experience using them.
There are more elaborate testers whereby one can adjust a gap the spark has to jump. You can mimic the effect by sacrificing a known good plug and bending the ground electrode out straight. This test is done with the plug laying on the cylinder head, not installed. The thinking is if the spark will jump a 1/4" gap outside the engine, it's likely to jump a .028" gap under compression.
I have a timing light, are you just clamping the sensor around the plug cable and seeing if you get it to strobe? I can also pick up a in line spark light this evening.
QuoteI have a timing light, are you just clamping the sensor around the plug cable and seeing if you get it to strobe?
Yes - spark plug and cap installed with the inductive pickup sensor clamped around the high tension wire. Connect the timing light to the battery and squeeze the trigger whilst cranking the engine over to hopefully see the consistent flash of the strobe.
Quote from: Rikugun on May 03, 2017, 03:40:13 PM
QuoteI have a timing light, are you just clamping the sensor around the plug cable and seeing if you get it to strobe?
Yes - spark plug and cap installed with the inductive pickup sensor clamped around the high tension wire. Connect the timing light to the battery and squeeze the trigger whilst cranking the engine over to hopefully see the consistent flash of the strobe.
Its lighting up fine. I just replaced the plugs as well along with blocking of the YICS and no change. Maybe to elaborate on what happens is I hold down the starter and it starts turning at a quick pace, the engine starts to catch and just barely fire with help of the starter and it ALMOST gets going to idle but it just doesn't quite catch. Starter fluid doesn't make any difference nor does dripping some gas in.
She started!!! I pulled the carbs apart again and dipped them another time around.
She idles quite well for not running for almost 5 years.
Now to fix all the other things!
Thanks everyone for the help and putting up with all my questions!