Hello folks - this all began after my bike was knocked over during the winter. It spent about 1/2 of the day on it's side before I found it. Apparent damage was no more than the right side bar end, which a forum member helped me replace.
I was able to start it immediately afterwards but minutes after, the bike would no longer hold an idle...then, it would not even start. From what I can tell, the engine turns over and I can here the click of the starter. There is the sound of air coming out of the exhaust as the engine turns, but there is ZERO combustion. There is also ZERO smell of fuel nor is there backfiring. My sense is that a fuel/air mixture must reach the engine and get ignited in order to have combustion. Even without ignition, I should be able to smell that mixture reach the exhaust with the occasional backfiring. This is not happening but I don't know why. I have now reached the end of what I know. Any fresh ideas would be very helpful. Here is what I've checked/done.
#1: fuel - clean/no water/lights up when i set fire to it; i am able to get fuel from both drain screws; float height is appropriate using the plastic tube method on the gstwins howto page; both petcocks should be functional as the drain screws are distal to them.
#2: ignition - i replaced both spark plugs even though the old ones were producing a spark just fine; i can see the spark when i have the wires hooked up to the plugs outside of the engine; the battery power seems fine - i am also using an external jumpstarter device that is fully charged; with the plugs out, i can feel a push of air whenever the engine turns over
#3: air - i checked the airbox and airfilter for oil/debris; it is clean and there was no evidence of oil; i have opened up the carbs and there appears to be no damage to any of the components (needle, seals, etc.)
have you tryed to start the bike then checked to see if your plugs are wet?
Quote from: joshr08 on April 14, 2009, 10:21:23 AM
have you tryed to start the bike then checked to see if your plugs are wet?
the bike has been in a vertical position for weeks since the incident. when i went to change the plugs, there was oil around the screw part of the left plug. after i replaced the plugs, tried to start the engine & re-inspected the new plugs...i found the same thing. some oil around the screw portion of the left plug. :dunno_white:
what i mean is can you smell gas on the plug?
Quote from: joshr08 on April 14, 2009, 10:33:07 AM
what i mean is can you smell gas on the plug?
oh...i didn't notice any smell of gas on the plugs. granted, i don't have a great sense of smell...but it looked like the plugs tips were brand new out of the box despite 10-15minutes of trying to start the engine. not even the slightest amount of soot.
did it fall on the clutch side of the handlebars? Oh wait a minute, it turns over but won't light. I dunno try a little starting fluid in the airbox and see if you can get a burp out of it. On the other hand I had a buddy who flipped his Suzuki Samurai, and all the oil went up into the head. He didn't wait for it to drain back down before he cranked it and toasted his engine. But I don't think that is your problem unless there was boocoo gobs of white smoke that poured out when you started it.
no it fell on the right side from his first post thats how i take it.
Quote from: joshr08 on April 14, 2009, 04:19:44 PM
no it fell on the right side from his first post thats how i take it.
exactly...btw, i noticed that the previous owner installed a fuel filter that looks like this:
http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/FuelFilter
mine looks like there is fuel + air in the filter. i have never really looked at the thing before and don't know if this is the way it should look.
that sounds like the way it should look. hmmmm.....no gas leaked into your crankcase did it? Maybe when it was laid over the float valves fell open and gas filled your crankcase.....have you checked your oil level?
Quote from: commuterdude on April 14, 2009, 05:25:55 PM
that sounds like the way it should look. hmmmm.....no gas leaked into your crankcase did it? Maybe when it was laid over the float valves fell open and gas filled your crankcase.....have you checked your oil level?
oil level was good.
again, there seems to be no combustion. float levels are good when checked with a clear rubber tube and the drain screws open.
im guessing somehow your not getting gas. your plugs should smell like gas when you try to start the bike if its not firing if there not wet with gas your not getting any into the motor and thats why its not starting.
From what you describe, you have air (comes out the exhaust) there is spark (you've seen it) and there is fuel to the carbs (you got it out the drains). But there is not fuel in the cylinder (no smell, not wet, etc).
Really dumb-ass question - is choke on/working? Stupider things have happened (ahem, cough, cough), that's why there's FINE-C (evidently FINE-CC for the younger or more recent generation...there was no clutch safety switch on my first bike, and if it's in neutral you don't need one IMHO)
Anyway, that points to some sort of problem with the carbs. You've checked the float height. Your bike sat all winter with fuel in it? Perhaps they are simply plugged full of varnish, and what you need is a really good carb cleaning...
Try a touch (not too much) of starter fluid to verify that it catches/fires if you feed it some fuel.
Quote from: DoD#i on April 14, 2009, 06:28:27 PM
From what you describe, you have air (comes out the exhaust) there is spark (you've seen it) and there is fuel to the carbs (you got it out the drains). But there is not fuel in the cylinder (no smell, not wet, etc).
Really dumb-ass question - is choke on/working? Stupider things have happened (ahem, cough, cough), that's why there's FINE-C (evidently FINE-CC for the younger or more recent generation...there was no clutch safety switch on my first bike, and if it's in neutral you don't need one IMHO)
Anyway, that points to some sort of problem with the carbs. You've checked the float height. Your bike sat all winter with fuel in it? Perhaps they are simply plugged full of varnish, and what you need is a really good carb cleaning...
Try a touch (not too much) of starter fluid to verify that it catches/fires if you feed it some fuel.
choke on
it would really suck if the carbs have crap in them. all i did when i checked them before was open the tops to inspect the pins, seals...nothing was broken. i agree that it must be something preventing fuel from getting to the engine. since air seems to be moving through the engine, the carbs are probably the culprit.
is there any way around physically removing the carbs to clear the fuel pathways in carbs?
since fuel is getting to the float, it must be something between the float and the inlet to the engine.
Verify that your plugs get wet when you crank it. Josh is right. If they're dry, you have clogged jets. If they're wet, you have an ignition problem. The ignition cover is on the right side of the engine, the side it fell on.
alright...i'm going in. (removing the carbs) btw, i live in a 5th floor apartment in manhattan without a garage. however...we do have an elevator that just barely fits the gs500e if you position it diagonally. :icon_twisted:
the bike's now in my apartment. :thumb:
Quote from: sclegend on April 15, 2009, 07:22:37 PM
alright...i'm going in. (removing the carbs) btw, i live in a 5th floor apartment in manhattan without a garage. however...we do have an elevator that just barely fits the gs500e if you position it diagonally. :icon_twisted:
the bike's now in my apartment. :thumb:
Sweet! I've always considered bringing my GS inside to work on it at night and when the weather out isn't good, but I'd have to ride it up a couple of steps to get there.... Also, every time I dig into my carbs, I end up spilling gas everywhere. I hope you put a tarp down or something that will protect your floor from gas. If you don't you'll quickly find that gasoline is a fantastic solvent that will eat all kinds of things like varnish on wood floors, or glue and dye on carpet...
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Sweet! I've always considered bringing my GS inside to work on it at night and when the weather out isn't good, but I'd have to ride it up a couple of steps to get there.... Also, every time I dig into my carbs, I end up spilling gas everywhere. I hope you put a tarp down or something that will protect your floor from gas. If you don't you'll quickly find that gasoline is a fantastic solvent that will eat all kinds of things like varnish on wood floors, or glue and dye on carpet...
[/quote]
good call...i should try to keep as much of the deposit as possible.
try yanking off the airbox and spraying some starter fluid in the back of both carbs. then crank it and see if it turns over. after you try that, hold your hand over the back of one of the carbs lightly to make sure you're still getting a good suction when then engine cranks.
if you have good spark, then it's likely that the engine somehow isn't pulling in gas. i'm no expert at this stuff, but i closely watch a mechanic diagnose my bike (very recently) and that's what he did. for me, it turned out that the petcock was clogged or something and wasn't adequately providing fuel to the carbs. my bike had also been dropped before i bought it...
so that was an experience. i took the carb apart. a bit of crap in the floats (stuck on the bottom) which i cleaned out, but everything else seemed fine. none of the jet holes seemed plugged.
this carb was recently rebuilt by the previous owner and all the replaceable parts looked new. i was hoping to find the problem here but there wasn't anything obvious.
You didnt lose the little o-ring in there did ya? re-primed the carbs. check all vacume lines especially the one to the petcock. If all else fails send your carbs to buddha to run through. I think he charges like $50. Sounds like no fuel.
how do i verify that fuel can get from my float bowls to the intake of the engine? which jet do i spray stuff in...and where should it be coming out?
i'd like to square that one away before re-installing the carbs.
my next todo is to remove the in-line fuel filter. it apparently looks fine, but i want to remove all suspects.
some newbie questions: can i use carburetor cleaner as starter fluid? once i re-assemble the bike, how do i get the starter fluid in the engine (through the spark plug sockets?)
Starter fluid - spray in the airbox (at the carb air inlets - the big hole facing the airbox), or into the air cleaner if you have the air cleaner installed.
Carb cleaner is not starter fluid.
alright, with the airbox and carb still off the bike i went ahead and turned the engine over to check for adequate vacuum.
there is certainly sufficient suction at the inlets to the engine when i do this.
the problem is narrowing down to the carb...but my carb seems fine. :mad:
Since all indications are that the problem is the carb, if you can't see anything wrong with it, it might be time to pack it up and ship it to Buddha for the expert look-over & fix at $50.
However, if you just want to keep plugging at it he and/or others will have more specifics for you to check - clear pics of the carb may help them. I have not had to mess with mine on this bike, and the last set I really got into were off a Corvair, so I can't tell you that you need to poke a wire through the hole 3 mm to the left of the frammitz. But I'm pretty darn sure that something is not right with the carbs from the concatenation of all your symptoms and observations to this point.
Quote from: DoD#i on April 16, 2009, 08:34:18 AM
Since all indications are that the problem is the carb, if you can't see anything wrong with it, it might be time to pack it up and ship it to Buddha for the expert look-over & fix at $50.
However, if you just want to keep plugging at it he and/or others will have more specifics for you to check - clear pics of the carb may help them. I have not had to mess with mine on this bike, and the last set I really got into were off a Corvair, so I can't tell you that you need to poke a wire through the hole 3 mm to the left of the frammitz. But I'm pretty darn sure that something is not right with the carbs from the concatenation of all your symptoms and observations to this point.
thanks...i will do this
here's another thought...could i have had an airlock? :icon_idea: due to the acute nature of the problem and lack of ANY internal damage, i'm adding this to a high position on my differential diagnosis.
How's the carb vent hose (the one from the upper Tee)? If that's clear, not likely to be an airlock. If it's plugged, full of mudwasp nests, etc, might have something to do with it. But you have proper float height, presumably after running the drains (?), so probably not. The other possible airlock (tank vent) would not be consistent with fuel out the drains, and is easily checked by opening the fuel filler.
Quote from: DoD#i on April 16, 2009, 09:34:21 AM
How's the carb vent hose (the one from the upper Tee)? If that's clear, not likely to be an airlock. If it's plugged, full of mudwasp nests, etc, might have something to do with it. But you have proper float height, presumably after running the drains (?), so probably not. The other possible airlock (tank vent) would not be consistent with fuel out the drains, and is easily checked by opening the fuel filler.
upper tee is clear. does proper float height preclude any problems upstream?
take the airbox off and spray in some starter fluid right where the airbox connects up to the carbs. just leave the airbox off and try cranking the engine. i suspect it will want to start up. if that's the case, then next thing to do is rule out the petcock. you can do this by disconnecting the petcock from the carbs and connecting the main from the tank directly to your carbs. also if you turned that valve on the bottom of the tank to 'off' while connecting up the hoses, make sure you turn it back on or youll get nuttin!
It may just need some extra juice, this was happening to me so I hooked the battery up to my car with jumper cables and kept cranking it until it turned over, then let it run for a while with the choke on.
You can also remove the spark plugs and spray some carb cleaner/starter fluid in and then put the plugs back in hand tight and try turning it over. If it starts let it run for a while until you can turn off the choke without it stalling.
Update: it's raining outside so no point in bringing the bike down for a test today. However, lots of progress in terms of removing potential problems.
1. yanked the fuel filter. it wasn't clogged but looked like it was getting a bad bend in one of the connectors.
2. dumped all the fuel (into old pasta jars!) it was gross and separated in to 1cm water, layer of rust, and the remainder fuel
3. checked the petcock...on suction and all. works fine.
4. verified continuity between the float bowls and jets, vacuum hose and engine intake, etc.
5. put everything back together
6. bought new fuel, starter fluid, charging up the jumpstarter...can't wait for some sunshine.
damn...i know way more about this bike than i ever intended.
I'm back on the road!!!
Poured in new fuel today with the petcock in prime and the fuel filter removed.
Also sprayed some starter fluid before firing her up...started right up.
I think it was the funky fuel vs. kinked filter that was my problem.