GStwin.com GS500 Message Forum

Hi,

My bike is not starting.  I haven't ridden much in the past month, and it did get knocked over once since the last time I had it running.

I charged the battery, and even tried jump starting it with my car just in case it needed a little extra power.  It sounds like it's trying to start (not clicking sound, but normal starter sound), but just won't turn over.  What is most surprising and concerning is that I haven't been able to bump-start it, and that's always worked in the past.

Any ideas of what I might try before getting it towed to a mechanic?  Thanks,

--Jon

does it have gas??

Check the cable that tells the bike that the clutch is in. If the sensor isn't working, the bike won't turn over even with the clutch in. Also, will it turn over and not start or what? Do the lights come on?

Which side was it dropped on?

Scott

check the sensor on the side stand....if the side stand isn't pushing the sensor the bike will not turn over....


basicly, check the sensors and if everything is OK then take out the spark plugs and try starting the bike (it want start) but if it turns over without the spark plugs then you had alot of fuel inside the cylinders and that's why it didn't turn over...

The bike went down on the right side.

If I don't raise the kick-stand, then it doesn't make any starting sounds at all, but when the stand is up, it sounds like it's trying to start, but just won't turn over.  So I'm pretty sure it's not the kick-stand sensor.

How do I check the clutch sensor?  I recently replaced the clutch lever -- could that be related?

I'll try taking out the spark plugs.  Should the bike start without the spark plugs?  Is the reason to remove the plugs to allow the potentially flooded cylinders to air out?

What does the fact that it won't bump start indicate?

--Jon

If the bike went down on the right side then you MAY have messed up the ignition parts behind the round, right side cover.  There is a "whirling thingie" that times the spark to your plugs, as well as some pickup sensors and wiring.

Start by making sure you're getting a spark from each plug.  Unscrew each plug, put the spark plug wire back on, and touch the metal end to the engine block as you push the starter button.  You should see a definite spark jumping the gap.  (Hint: You may get a nice shock if you hold the spark plug against the engine with your hand.  Try to use something insulated.)

If one or both plugs fail to put out a spark, come back and we'll work from there.  The problem may be as simple as tightening some connections under the right cover, but it could get a little more involved as well.

it would be wierd if it's the ignition coil... cuase i skid my bike about 40ft on my right side... suzuki decal came off... there is this big hole... and i can see this thing moving... but the bike still rides like a charm... ^^ suzuki people are good...

I don't suspect the coils themselves, since they're up under gas tank on the inside of the frame.  But depending on what kind of "jolt" the bike got, the electricals behind that right-side cover may not be sending a signal TO the coils.

Another thing, make sure the battery is fully charged.  Perhaps it had a hard time starting the first few times and you wore the battery down.  Now it barely wants to turn over?

ASLAM.

OK if the bike is turning over but the thing isn't starting... and battery is powerful and it fell over... I suspect hydrolock... take out the spark plugs and turn it over with starter... if it spits gas from spark plug hole... its hydrolock. Lucky you didn't bend a rod or something. The put the plugs back in and try to start it.
Cool.
Srinath.

Quote from: jwylerThe bike went down on the right side.

If I don't raise the kick-stand, then it doesn't make any starting sounds at all, but when the stand is up, it sounds like it's trying to start, but just won't turn over.  So I'm pretty sure it's not the kick-stand sensor.

How do I check the clutch sensor?  I recently replaced the clutch lever -- could that be related?

I'll try taking out the spark plugs.  Should the bike start without the spark plugs?  Is the reason to remove the plugs to allow the potentially flooded cylinders to air out?

What does the fact that it won't bump start indicate?

--Jon

so, the bike has power (battery) but doesn't turn over...once again, take the plugs out and then press the start button (no, it will not start but if it turns over this time, then it was hydrolocked)

if that doesn't help..make sure that the bike is in neutral...when you said that when you have the kickstad down the bike doesn't do anything, but when it's up then it makes a clicking noise....i'm about 90% sure you have a problem with your neutral sensor....first let the clutch out and see if the bike roll's...if it roles with the clutch let out then the bike is in neutral...it if doesn't start after that you have a problem with the electronics and sensors

You replaced the clutch lever... ok on a pre 96 bike you needed to have unscrewed the clutch sensor unit, then put the lever in and then put the sensor back in... else its screwed up... post 96 I believe you can swap the lever wihtout thinking about the switch... it automagically fixes itself.
Cool.
Srinath.

From Jon's first post:

Quote from: jwylerIt sounds like it's trying to start (not clicking sound, but normal starter sound), but just won't turn over.  What is most surprising and concerning is that I haven't been able to bump-start it, and that's always worked in the past.

No clicking, engine is spinning, just not firing up.

Nobody else thinks it might be bad spark / ignition system?

He said not turning over... I interpret that to be... the starter goes whirr whirrrrrrrr whirrrrrrrrrnnnnn... but doesn't succeed in getting the motor turning quick enough.
Cool.
Srinath.

Quote from: KerryFrom Jon's first post:

Quote from: jwylerIt sounds like it's trying to start (not clicking sound, but normal starter sound), but just won't turn over.  What is most surprising and concerning is that I haven't been able to bump-start it, and that's always worked in the past.

No clicking, engine is spinning, just not firing up.

Nobody else thinks it might be bad spark / ignition system?

he didn't explain good...he said it's not a clicking sound, but normal starter sound but doesn't turn over  :?
it's either turning over or not turning over at all...how can it sound like it want's to start if the engine isn't turning over  :?
maybe i just don't get it  :dunno:

Haven't had a chance to try with the spark plugs out -- I'll try tomorrow, but perhaps I'm mis-using the term "turning over."  What I meant is that every thing sounds normal short of it actually starting.  Sounds like the motor starts to spin at least a little bit.  

I didn't encounter any sensor connection when I swapped the clutch lever.

This "hydrolock" phenomenon -- if the engine is flooded, shouldn't it air out eventually on its own?  It's been a couple of weeks since it was knocked over.

I'll try starting without the spark plugs tomorrow and let you know how it goes...

--Jon

just make sure you take out the plugs and put the spark plug wires back on the spark plug even though they are not screwed in the cyl head and put the plug on the side of the engine....this way you will see if there is a spark and you will not burn your coil like i did  :x

Flooding actually refers to carbs... when flooded the carbs will send liquid fuel into the motor... and kill the spark... The hydrolock thing is where the gas fills up the cylinder when carbs overflow and when you try to start the gas isn't compressible... and its taking up volume... and it can get bad enough to bend a connecting rod...
Cool.
Srinath.

So I took out the plugs and tried starting it, and no fuel came out, so it appears it is not hydrolock.

Then I tested for sparks, and both plugs sparked just fine outside the cylinders.  I could also see movement of the pistons through the plug hole, so I assume the starter motor is working.

As far as the clutch sensor, I did not have to do anything with that while changing the lever, even though it is a pre-96 bike, unless I missed something there.  How would I test to see if that is the problem?

It isn't the kick stand sensor.

I charged the battery before my last try, and the battery is only a year old, so I don't think that's the problem.

The tank is pretty full, and I've tried starting on all three fuel settings, so I don't think it's lack of gas.

I still am puzzled by the fact that it won't bumpstart.  I've had problems starting from time-to-time in the past, but never been unable to bumpstart it.  Do you think this might indicate something?

Now what?  Thanks for your help on this, guys...

ok, now your engine IS turning over and there is a spark...everything there is good......now the only problem that i can thing of is FUEL

asuming your timing is good, your bike may be lacking fuel...try this

put the petcock on ON and then draing both float bowls all the way untill fuel stops drainging from them...then put the bike on PRI and wait a minute or so...then (while on PRI) try draining the float bowls again but not all the way....just drain them a little to make sure there there is fuel inside of them...if the fuel comes out of the float bowls after you drained them all the way then you have a good fuel flow to the carbs...

is the bike doesn't start after you did that then it could be a bad chocke cable....try this: put the petcock on PRI and pull the chocke all the way...then twist the throttle a little while you are cranking the engine

hopefully this helps

How do I "drain the float bowls"?

(http://users.sisna.com/KerryKJB1/FujiFotos/FloatHeight/DSCF2431.jpg)

this is a picture of the bottom of the carb (float bowl)...see the little screw on the side...when you turn it counter clockwise the fuel will drain on the bottom of that little metal tube...if you have a small tube, just attach it to the bottom part of the bowl (so you don't have gas leaking on the engine) and then turn the screw untill fuel come out


thanks for the pic kerry  :thumb:

Did just as you said... drained the float bowls, set to prime, and checked the flow.  Fuel came out of the drain on both sides just fine after that.

Time to give up and take it to a shop, or anything else to try?

I still haven't heard any attempts at an explanation of why it won't bump-start, since like I said, that's never been an issue before.

Thanks for the continued help on this, --Jon

Also definitely not the clutch limit switch, as it appears a previous owner must have soldered the wires together so that it'll start with the clutch engaged or not.

let me get this straight......when you took the spark plugs out, you could hear the engine turning over when you press the start button, right?
if so, then all the other sensors are good and don't worry about them...

when you put the plugs back and press the start button, do you hear the engine cranking? you said you seen spark from the plugs so that is good....

if you try to start the bike and you can hear the engine turning over, you have a spark, you have fuel geting to the carbs, then everything there is good....

the only other thing i can think of is the timing...the timing could be off and that's why it doesn't want to start... just take it to the shop and hopefully they want rip you off

Check that the choke cable is not binding and is activating the choke.

Quote from: GRUthanks for the pic kerry  :thumb:

I posted a more self-explanatory version of this picture recently.  (I can't remember where.)  Hopefully it will be helpful for various purposes in the future....

http://www.bbburma.net/MiscFotos/DSCF2431_Idle_Drain_Mixture_Screws.jpg

====================================

Meanwhile ...

Jon, I'm still not convinced that your electricals are A-OK.  You seem to have fuel flow, there is no cut-out switch problem, and you're getting spark.  BUT...

..."getting spark" - in my experience at least - isn't "definitive".  I had a break in the signal generator circuit, and even though I "got spark" on both plugs when they were pulled from the block, the engine would still only run on one cylinder.

Now, your problem has a 99% chance of NOT being the same as mine, because the break in my circuit was on the left side of the bike.  But the signal generator itself is underneath that right-side cover, and there could be a problem elsewhere in the same circuit.  If you're handy with an electronic multimeter (ohmmeter) there are a few simple measurements you can take before you give up and take the bike to the shop.

If you're interested enough to wade through a multi-page message thread before surrendering, take a look at
Narrowing down the problems to a broken bike

After getting a feel for the background of the (hopefully relevant) scenario, try filling out the checklist at the bottom of the 2nd page of posts.  Let us know what you find!

EDIT: Changed link from sisna.com to bbburma.net.

Just an odd thought; its' not likely to be the culprit, as the starter manages to rev the engine over, but since you said knocked over to the right: Acid level in the battery is OK? It could have drained if the bike was laying on the right side for a considerable time.

A lame battery might drop in voltage enough when starting to cause all sorts of problems.

I charged the battery with a trickle charger, and it gave me a "green light" indicating it was charged, so I assume the acid level is OK.  Looked like it could use a spash of water, but not significantly low.

I'll give the electrical checklist a try.

Another thought/question: do you think I need to rebuild the carbs?  Isn't it possible that the bowls are filling, but the cylinders aren't actually getting any fuel?  (If so, do you think the "How To" on this site is comprehensive enough for someone with limitted bike/auto mechanics experience, but is mechanically inclined?)  I should note that I was never able to get this bike over 60 mph, which I'm guessing might indicate the carbs aren't super clean, though my tank is completely rust-free.)

Quote from: jwyler
Another thought/question: do you think I need to rebuild the carbs?  Isn't it possible that the bowls are filling, but the cylinders aren't actually getting any fuel?  (If so, do you think the "How To" on this site is comprehensive enough for someone with limitted bike/auto mechanics experience, but is mechanically inclined?)  I should note that I was never able to get this bike over 60 mph, which I'm guessing might indicate the carbs aren't super clean, though my tank is completely rust-free.)

yes, i think you should rebuild the carbs....there is a big possibility that the jets are pluged from dirt and rust....after all the things i told you to do, and basicly all of them turned out OK now it's time to take out the carbs and check them out....

while you have the carbs out for a cleaning, change the main and pilot jets and inspect all the carb pieces.

So I'm rebuilding the carbs now...

But they look very clean.  I'm doubting that was the problem...

The air filter is quite dirty, though.  That wouldn't keep the bike from starting, would it?

not really...i seen tons of dirty air filters and the engine ran fine...

rebuild the carbs and try to start it again...make sure to clean the jets if you arn't replacing them

So I rebuilt the carbs, even though they didn't end up being dirty.

I'm 90% sure that I've reinstalled them correctly.  (Does one of the 4 hoses from the tank and 2 of 4 from the carburetor -- the one from the left carb and the top T -- go to ambient?)

But now I don't have fuel flowing to the bowls!  I put it on Prime and gave them a few minutes to fill, and nothing.  I did turn the fuel valve to On.

_4_ hoses from the tank?  I'm only aware of 3.  Hmmmm.

See if the pictures on my Fuel Hose Routing page (http://www.bbburma.net/FuelHoseRouting.htm) help at all.
If you want to print it out, Rema1000 posted a nicely-organized 1-page PDF version at
http://grapeape.specialgreen.com/~bcarlson/gs500/images/HoseRouting.pdf

There is one hose that is not mentioned here - the thin one that connects to the underside of the fuel tank itself.  It has a right angle bend in it near the upper end, and the lower end is near the right footpeg.  This hose drains overflowed fuel or rainwater (which can collect under the filler cap) to the ground.

EDIT: Changed link from sisna.com to bbburma.net.

Quote from: jwylerI'm 90% sure that I've reinstalled them correctly.  (Does one of the 4 hoses from the tank and 2 of 4 from the carburetor -- the one from the left carb and the top T -- go to ambient?)

But now I don't have fuel flowing to the bowls!  I put it on Prime and gave them a few minutes to fill, and nothing.  I did turn the fuel valve to On.

Those two statements are related. The top hose from the left carb is the vacuum hose that activates the petcock. Without that, no fuel flow. (when the Engine's running, that is. To prime the carbs yo need the respective setting on the petcock, as the carbs won't deliver vacuum.

The top T hose indeed goes to ambient.

About PRI not working: Any kinks in the hoses? It's easy to get some when assembling that can of rubber worms.

Kerry, there are 4 hoses on the CA model tank. The 4th goes to the emissions canister.

Quote from: jwylerSo I rebuilt the carbs, even though they didn't end up being dirty.

But now I don't have fuel flowing to the bowls!  I put it on Prime and gave them a few minutes to fill, and nothing.  I did turn the fuel valve to On.

Even if the carbs don't appear to be dirty, if they have been sitting long enough with old gas, the gas may turn into a varnish and gum up the jets and all the little holes in the carb. Soaking in carb cleaner or spraying with the little red tube into all the little orifices and making sure you see the fluid coming out some other little orifice will help ensure that you have nothing blocked. Just be careful not to spray any rubber parts.

Did you turn on the On/Off valve under the tank? Also, put on Prime and tap the float bowl with the butt of a screwdriver to get the float valve loose, sometimes when it's dry it sticks in the seat.

you said the bike was sitting for a while.  have you tried fresh fuel?

When you try to start the bike, do you open the choke all the way? Maybe try partway?

Quote from: jwylernow I don't have fuel flowing to the bowls! I put it on Prime and gave them a few minutes to fill, and nothing. I did turn the fuel valve to On.

How do you know the bowls aren't getting any fuel?  Try the following, with the fuel selector in the PRIme position:

1) Open the float bowl drain screws.  Does fuel come out for a minute or more? If so, then the bowls are getting fuel.  If not, then close the drain screws and continue.

2) Pull the hose from the lower T-fitting between the carbs.  Does fuel come out of the hose?  If so, then there must be a blockage between the lower T-fitting and each carb, or within the carbs themselves.  If not, then reattach the hose to the T-fitting and continue.

3) Pull the other end of the same hose from the frame-mounted petcock.  Does fuel come out of the petcock?  If so, then there must be a blockage in the hose.  If not, then reattach the hose to the petcock and continue.

4) Pull the RES hose from the frame-mounted petcock.  (It's the one attached to the right side, or rear, of the petcock.)  Does fuel come out of the hose?  If so, then there must be a blockage in the petcock.  If not, then reattach the hose and continue.

5) Pull the RES hose from the tank-mounted petcock.  (It's the one attached to the longer downtube, on the left or towards the front.)  Does fuel come out of the tube?  If so, then there must be a blockage in the RES hose.  If not, then reattach the hose and continue.

6) At this point you only have 3 options: A) There is no fuel in the tank, B) The tank-mounted petcock is not turned on after all (the screwdriver slot must be

vertical), or C) There must be a blockage in the in-tank filter or outlet.

7) Once the blockage is found and fixed, you may need to work your way back DOWN the fuel supply system, making sure that fuel flows at each junction.  Alternately, you can just try to start the bike!  :) [/list]

==================================

If the motor still won't start, will it at least still "crank" like before?  I'm curious about the results of your earlier plan:

Quote from: jwylerI'll give the electrical checklist a try.

STARTED, FINALLY!!!   :)  :)  :)

After putting this off for several weeks, several months after it last ran, I've finally got her going.  

Looks like rebuilding the carbs did the trick.  Lack of fuel was caused by the tank petcock being OFF.  Hot tip: don't attempt to reassembly carbs for the first time at night in the dark!

Big thanks to all of you for your continued help on this.  I've got a couple of remaining questions now:

- How do I adjust the idle, and what do I adjust it to?
- The choke lever is now stiff, and isn't easily pulled to full, but appears to be attached to the carburetor correctly.  Any thoughts on that?  Need some lubrication or something?
- I'm having a hell of a time securing the hose from the left carb to the back of the petcock cause I just can't get my hands in there.  Any tricks to that?

Thanks again, --Jon

Quote from: jwylerSTARTED, FINALLY!!!  [...]  Looks like rebuilding the carbs did the trick.

Congratulations!

Quote from: jwylerLack of fuel was caused by the tank petcock being OFF.

Makes sense.  Been there, done that!  :oops:

Quote from: jwylerHow do I adjust the idle, and what do I adjust it to?

Turn the Idle Adjusment Screw.  Counter-clockwise (as imagined from above) to increase the idle, the other way to decrease.  The idle should be set to 1200 RPM (when the engine is warm).

Quote from: jwylerThe choke lever is now stiff, and isn't easily pulled to full, but appears to be attached to the carburetor correctly.  Any thoughts on that?  Need some lubrication or something?

Lubrication is the best guess.  The spring at the end of the cable isn't strong enough to cause problems, and the only other choice is a "sticky" pair of plungers in the fuel enrichening circuit.  (The 2 "plungers" are the items that the choke cable actually causes to move, down near the lower end.)

Quote from: jwylerI'm having a [hard] time securing the hose from the left carb to the back of the petcock cause I just can't get my hands in there.  Any tricks to that?

Can't think of any.  Just try, try again...!

EDIT: Changed link from sisna.com to bbburma.net