No start GS650

[eldoradoman]

You are marginal on the left coil, but I'd expect it to at least cough a little. How do those numbers compare to the voltage across the battery, and what is the voltage across the battery with the engine cranking over? Without knowing this information, it's tough to diagnose the starting/running problems.

In the first post in this thread you said that it 'seems to have spark". How did you determine that? ColorTune? Grounding each plug against the head?

I checked for spark by grounding the plugs against the engine, all seem to be about the same, hard to tell if they're blue though as I'm color blind, lol.

I'm still using the booster pack when trying to start it so it's definitely 12V. I suppose I should put the battery back in though and test it too...

[duaneage]

you have spark so the igniter and coils are working somewhat. That leaves timing and fuel.

Pull a plug, does it smell of gas? Is it in good condition? If no gas is smelt then see if the carbs have fuel by loosing one fuel bowl drain and see what comes out.

If no fuel, pull the carbs and clean them. There is a how to on the GSR homepage for this.

If you have fuel on the plug and they are in good shape make sure 2-3 are on one coil and 1-4 cylinders are on another. Reverse the pairs and see if that does it. during troubleshooting sometimes the pairs get reversed.

If there are bowl vent hoses still on the carbs going up where the tank is from the carb rack, take one and blow air into the hose for a few seconds. Sometimes this primes the choke circuit and sprays a little fuel to get it going. It worked for Tim Tom's 850 when it would not start.

[tom203]

duaneage said...
"If you have fuel on the plug and they are in good shape make sure 2-3 are on one coil and 1-4 cylinders are on another. Reverse the pairs and see if that does it. during troubleshooting sometimes the pairs get reversed"

Good point -easy to mix up. As you sit on bike left coil fires 1 and 4 (1 is under clutch hand) while right coil fires 2 and 3

[eldoradoman]

duaneage said...
"If you have fuel on the plug and they are in good shape make sure 2-3 are on one coil and 1-4 cylinders are on another. Reverse the pairs and see if that does it. during troubleshooting sometimes the pairs get reversed"

Good point -easy to mix up. As you sit on bike left coil fires 1 and 4 (1 is under clutch hand) while right coil fires 2 and 3

yeah, I tried reversing the coil wires already, still get the same result. Turns over and over but no sputter or nothing. Putting a drop of fuel in each spark plug hole doesn't get it to sputter either.

I do get fuel on the plugs. I thought it might have been flooded at one time as they were always wet, so I cranked it over for a couple minutes at a time with wide open throttle to clear it just in case, then took all the plugs out overnight to let it evaporate (if it was flooded at all), but still get the same result.

The battery isn't very good it seems, drops to 8volts or so during cranking, and went from 12v fully charged down to 11 pretty quick after cranking just a few times. It sounds weak compared to using my little booster pack when starting.

[eldoradoman]

you have spark so the igniter and coils are working somewhat. That leaves timing and fuel.

Pull a plug, does it smell of gas? Is it in good condition? If no gas is smelt then see if the carbs have fuel by loosing one fuel bowl drain and see what comes out.

If no fuel, pull the carbs and clean them. There is a how to on the GSR homepage for this.

If you have fuel on the plug and they are in good shape make sure 2-3 are on one coil and 1-4 cylinders are on another. Reverse the pairs and see if that does it. during troubleshooting sometimes the pairs get reversed.

If there are bowl vent hoses still on the carbs going up where the tank is from the carb rack, take one and blow air into the hose for a few seconds. Sometimes this primes the choke circuit and sprays a little fuel to get it going. It worked for Tim Tom's 850 when it would not start.

I took the carbs apart and cleaned them already but it didn't change anything.

[tom203]

Assuming you still got airbox and air filter box on, try this... remove air filter element, block openning with hand, plastic cover, etc. and crank it . This puts alot of suction on "choke" pickup tubes and sometimes gets extra gas up to intake manifolds. Remember that this is an enrichment system,NOT a plate that blocks front of carb throats.
If you got fuel,air, and a spark at about the right time-should fire.

[eldoradoman]

Ok, so I'm getting nowhere with this. I tried going through the ignition system testing procedures here: http://members.dslextreme.com/users/...-ends.html#A04
but get stuck at testing resistance betweeen the coil plug caps. I get no reading at all for either coil, but they both have just under 5ohms resistance between the leads on the back.
I have one coil that's only getting 10V and the other gets very hot with the key turned on but provides a good spark when cranking.

My starter switch and kill switches are getting juice and light up my test light when I press them but the starter button still will not engage the starter. So
I'm still jumping the solenoid.

[tom203]

You got spark, so skip further ignition tests for now- we need fuel, any sign of fuel on plugs after some cranking? with "choke" fully activated.

[eldoradoman]

You got spark, so skip further ignition tests for now- we need fuel, any sign of fuel on plugs after some cranking? with "choke" fully activated.

I haven't put the tank back on yet but dropping gas in the spark plug holes or spraying carb cleaner in the airbox doesn't get it to sputter or anything at all.

When doing these two tests:

1. The little back box or igniter is now tested as follows. With the ignition on, kill switch on, test for 12 Volt DC between the orange/white and the black/white wires in the plug going into the igniter. This proves that it is getting the correct voltage.
2. The next step is to prove whether the igniter is powering your coils. Remove all 4 spark plugs and connect the HT lead caps to a spark plug #1, #2, #3 and #4 which is grounded and located to enable you to see the spark. Ensure all the connector plugs are back in, except the one with the green and blue wires from the signal generator.

I cannot get any voltage reading for test 1, and there is no spark in test 2 when I unplug the signal generator plug from the ignitor when cranking over. Plug it back in and there's spark again. Does this mean there's no power getting to the ignitor?

[BigD_83]

I had a set of plug wires and caps that tested fine when the plugs were grounded against the head, but were a little stressed when put back into the head. The result was that I was getting good spark outside the head, but I have a major voltage leak/weak spark when put back in because they were arcing to the head, and the bike went from running just fine, to not being able to start. I redid one sparkplug cap, and it was a night and day difference as it went back to starting by just brushing the starter button.

Something to come back to if we can't find a fuel or timing issue.

If that isn't the case, then you could be flooding the engine. You have fuel and spark, and probably air, but it might be too rich. What happens if you try to start up the bike without the choke?

Have you had the carbs apart yet? I had a similar wet plugs/flooding problem with no start and some stoopid PO (ahem or CO- current owner) had forgotten to tighten down the pilot jets...

[eldoradoman]

I thought I had flooded it originally and went through steps to clear it out til the plugs were dry again when cranking, then slowly tried the choke, but to no avail.

I did have the carbs apart and cleaned them, but didn't mess with the jets, just adjusted a couple floats.

Maybe it is a plug cap, as I remember getting a shock from one when holding it and trying to check the plug for spark against the head. I tried brand new plugs too with the same results.

I had a set of plug wires and caps that tested fine when the plugs were grounded against the head, but were a little stressed when put back into the head. The result was that I was getting good spark outside the head, but I have a major voltage leak/weak spark when put back in because they were arcing to the head, and the bike went from running just fine, to not being able to start. I redid one sparkplug cap, and it was a night and day difference as it went back to starting by just brushing the starter button.

Something to come back to if we can't find a fuel or timing issue.

If that isn't the case, then you could be flooding the engine. You have fuel and spark, and probably air, but it might be too rich. What happens if you try to start up the bike without the choke?

Have you had the carbs apart yet? I had a similar wet plugs/flooding problem with no start and some stoopid PO (ahem or CO- current owner) had forgotten to tighten down the pilot jets...

[gustovh]

You need to check and make sure that the cams are in correct timeing. I just completed a project that the intake cam was out of time only 1 pin and was a pain to start.

Logic says that if you have spark and are getting gas what is left?

That said if your battery is iffy, she may not run, but a good bat fires em right up.

[BigD_83]

There seem to be a number of issues in play with the bike, and you're probably going to have to go through all of the basic maintenance if you have not yet done so, even if it means just finding your baseline. Hopefully you have both time and space to work on the bike. Winter is coming up, and you should be able to get this bike sorted out in time for the spring.

Now...where are all the photographs?

[eldoradoman]

Okay so I got it running again. It's backfiring periodically, more at lower rpm's, less at high rpm's and once it's been running for a few it's a bit better. So I'm thinking it's getting too much fuel/not enough spark. Like I posted before, the O/W wire going to the left coil is only supplying 10volts and the spark is weak on those two plugs. So if I replace/fix that wire then it should help (in theory)?

It seems to start harder now where I need to hold the choke in much longer also, is that still a symptom of weak spark?

[BigD_83]

If you are holding the choke for longer, then you are giving it more fuel, longer, which could mean you have fuel supply issues, a weak spark, or both. However, 10V is a big drop in voltage, so connector cleanup and/or coil relay mod should help there.

Backfires can be lean or rich. When you say backfiring, is it firing on the exhaust side or back through the carbs and airbox?