Dead Bike

[Ant]

Right guys (and girls), bike diagnostic time.
My poor Bandit has been sat neglected and unridden outside (covered) for 2 months We finally get some sun around here and it won't start.
The starter motor turns the engine over just fine, there is just no ignition. Not even a slight "catch" on even one cylinder, it just doesn't do anything.

So far I have done the following:
Checked the fuses to make sure the ignition circuit isn't dead. Check.
Drained carbs in case there is any water. Check.
Disconnected the fuel tank and turned the engine over to try and empty the fuel system. Check.
Cranked the engine with both full choke, half choke, no choke. Full throttle, half throttle, no throttle and all the possible permutations of that. Check

Now I know you're going to say "take the plugs out and see if you're getting a spark" but I reaaaaaally don't want to do that until I've exhausted any other possibilities. The plugs are a pain in the arse to get to!

So what could be the problem and what can I do to check it? Obviously if there are no other non-invasive methods then I'll have to pull it to pieces and get at the plugs.

[bahwolf]

Had a dirtbike once that wasn't ridden for several months. Wouldn't start. Discovered some critters had made a nest in the airbox.

[Scratch33]

Hmmm.  Bad gas?  Presuming you got any/all stale fuel out of the carbs, you might try disconnecting the fuel line and cribbing in a temporary source of fresh fuel to see if it'll fire up.

[Scratch33]

Had a dirtbike once that wasn't ridden for several months. Wouldn't start. Discovered some critters had made a nest in the airbox.

Oh yeah!  I've found mouse nests (along with seeds 'n other mouse foods) in my airbox before too.

[greench440]

Instead of removing a plug, find an old one to use for the spark test.  

[MadMax96]

It's most likely a fuel problem or an ignition problem - so you'll either have to pull the carbs and check for blockages in the jets or check and/or replace the spark plugs.

If you've never done the carbs before, the spark plugs will be an easier thing to check first.  After trying to start the bike, see if they are wet with fuel - that will tell you that gas is at least getting to the cylinders and that it's probably a spark issue.  Try using a wire brush to clean them off and you should be able to get it running somewhat - but I'd probably replace the plugs if you never have before (depends on age and mileage of bike too).

With my pod air filters on my G1 Bandit - I can pull the carbs, clean them, and put them back in under an hour so I usually start there.

Good luck...  

[Hickey]

I once had a bike with a bad battery.  It would crank the motor, run the lights, and prime the fuel system.  There just wasn't enough power left to make a spark.  Therefore it wouldn't start.  

Can you put it on a charger for a while to see if that helps?  Or even better, have the battery tested?

Next I'd check as many electrical connections as you can get to for corrosion.  Covered up, outside, in cold and rainy weather sounds like a formula for corrosion to me.

[Windblown]

Hears what I do with balky machines that have sat unused for a period of time:

Give it a healthy shot of starting fluid into the airbox. Hit the starter. If it doesn't at least cough then you have a dead ignition system. If it starts and dies and won't restart you have a fuel problem.  It's very possible that once you get it to fire with the starting fluid she'll run just fine.

I know folks don't like to use starting fluid but seriously, it's a quick and painless way to  A) get the motor running. or B) find out which subsytem is likely the culprit.

[Andrew]

Make sure the battery is fully charged (Hickey has a good point) check the water level and put it on a charger for a while.
If it still will not fire up starting fluid will certainly help determine if it is fuel or ignition related, just use it sparingly.

My personal bet is the battery is a bit weak (less than 10v at cranking may keep the ignition module from working)  that or the fuel that was in the idle jets dried out and is acting like a blockage.

Best of luck to you Ant, keep us apprised of the progress.

[Ant]

Thanks for the hints guys.
It isn't the battery, after trying for a while (I was outside for over 2 hours!) I had flattened the battery and hooked it up to the car so power wasn't a problem.

Unfortunately I don't have any old spark plugs to do the test with (my car is diesel) but I'm going to go out tomorrow and buy a new one. If nothing else then I will have a spare.
Personally I am leaning towards there being an electrical problem somewhere, I find it hard to believe that all 4 jets would block at the same time but then again they're all in the same condition and stranger things have happened at sea

What is this starting fluid? I've never heard of it before.

[Windblown]

What is this starting fluid? I've never heard of it before.

Mainly it's ether. Extremely flamable stuff. Availible in any auto parts store.  It shouldn't be used continuously since it burns much quicker than gasoline, - think mini explosion.

Now for the obvious question, is the petcock turned on?  

[squeezer]

Now for the obvious question, is the petcock turned on?  

Not all that silly a question, really.  My old Connie had me scratching my head one early spring day until I realized I just hadn't primed it enough.  Just not enough fuel in the carbs to fire her up.

[Ant]

Not all that silly a question, really.  My old Connie had me scratching my head one early spring day until I realized I just hadn't primed it enough.  Just not enough fuel in the carbs to fire her up.

Hehe, well unless some sod has found the petcock and turned it off then I don't think this is the case. I don't even think this bike has one! I've certainly never seen it or used it if there is one.

[county]

Check the kill switch.

[Ant]

Check the kill switch.

Done that too
The starter doesn't turn if the kill switch is off.

[Ant]

Update on the bike:
In between dodging rain clouds I've managed to trace the problem out of the engine block. I'm not getting anything from the HT leads so the problem must be futher upstream.

What is the most likely candidate? I'm about to nip to the office and get the oscilloscope so I can check the voltage going in to the coils but if that is dead then I'm not sure where to go next. Where is the electronic ignition controlled from? The dash unit?

[Andrew]

Usually there is an ignition module, possibly internal to the ECU.

You should see a solid 12v or there about to one of the primary wires to ignition coils with the key on
When cranking the bike the the voltage should not drop below 10.o volts
The other coil primary wire should be receiving a ground pulse. The ground pulse is what the ignition module/ECU is controlling.

Sorry, without the book on your bike, my knowledge is rather generic.
Just a thought, I for one have never seen an electrical module/component fail due to sitting for 2 months. Maybe you have a bad/corroded connection somewhere

[Explorer]

It sounds like your bike is loaded up. and by your description it may now be gas-washed.
Like others have said Check the battery, it sounds like it may have a bad cell in it.
Make sure the battery is good, like Andrew and others have said. Put some Sea fome in the tank, and replace the spark plug's. When you go to start it again, do the following.
With the choke OFF!  Hold the throttle wide open while cranking the bike over, it can take a few minuets for the motor to come to life. At first it will seam like nothing is happing, then it will start acting like it's coming to life, then it should roar to life

This has happened to me a few time's and this has worked for me

[Ant]

Usually there is an ignition module, possibly internal to the ECU.

You should see a solid 12v or there about to one of the primary wires to ignition coils with the key on
When cranking the bike the the voltage should not drop below 10.o volts
The other coil primary wire should be receiving a ground pulse. The ground pulse is what the ignition module/ECU is controlling.

I've finally found my Suzuki service manual for the bike so I now know where all the bits and bobs live (ignitor is under the battery in case anyone is wondering). The other good thing is that is has a list of expected voltages and resistance values around various points of the bike. One other thing I need to retest is that I am getting a spark, cylinders 1 and 4 are the same coil (I assumed they were separate) so I now need to test 2 or 3.

Just a thought, I for one have never seen an electrical module/component fail due to sitting for 2 months. Maybe you have a bad/corroded connection somewhere

That is what I was thinking as well, the trick is to find the corroded connection
Thanks guys, keep the suggestions coming... I'm starting to get withdrawal symptoms  

[HipGnosis]

...Hold the throttle wide open while cranking the bike over, it can take a few minuets for the motor to come to life.

I would NEVER use any starter for a minute straight.   10, maybe 15 seconds at a time.  Then at least a short rest for the battery and starter before hitting it again.

I wouldn't bother testing the other coil.  You know you have an ignition problem.  I'd check or bypass the 'safety switches'; side stand, clutch, neutral...

Has the bike had a chance to fully dry out?  

FYI, there is a tool to see if you have spark w/o pulling a plug.  It looks sorta like a metalic pencil w/ a small neon light.  I've had mine so long I don't know the name of it or the brand.  Hold it against a plug wire as you crank the engine.  Kinda hard to see the light in direct sunlight, but that shouldn't be problem in the UK  {smirk}.

Good Luck