1988 Suzuki GSX600F Katana not firing | GTAMotorcycle.com

1988 Suzuki GSX600F Katana not firing

N

NiagaraRider

Well-known member
Hey there. A few weeks back I bought a 1988 katana 600. It ran pretty well. A couple of days ago I went to start it and it wouldn't hold an idle - it would just stall out, even with the choke all the way out. Even after holding the bike at 3000rpm for 10 minutes, it still stalled out. It was in neutral, kill switch off, kickstand up, etc. I rode it around for about 30 minutes after just throwing it into gear and taking off, and it idled fine. Now I tried to start the bike this morning, and it cranked but didn't fire except a burp or two. I checked the spark and plugs 1 and 4 have no spark. Does anyone know what the issue might be? I tried cranking with a truck battery to give it more cold cranking amps, but still no spark. What is the output at the coils meant to be? Thanks for the help.

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No rust inside of the tank. Forgot to mention I sprayed ether into the intake, and it wouldn't fire then either. Just got one big backfire.

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Could be the coils id 1+4 are dead. Confirm if the firing order is 1+4 and 2+3. Though if just 2 of 4 aren't firing, it should still run.
 
1 and 4 are on separate coils, so it would have to be that both coils are shot, but the bike ran fine a few days ago. The chances of both coils going kaput at the same time are pretty low, right?

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Check if your carbs are getting fuel?

The thing is with old bikes you'd need know how to wrench or they'll be expensive like a high maintenance girlfriend.
 
The bike has no spark though - I took the plugs out of the cylinders and grounded them on bolts and there a no spark from either coil.

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Not that the folks over here arn't great for technical questions but kats have a great bike specific forums with allot of troubleshooting info available for all years.

http://katriders.com/

always best to check the bike specific forum were available.

If the bike isn't sparking then it could be

Dead battery
Bad plugs (just dirty)
Bad Plug wires
coils wiring to the coils etc

Coil relay mod for the Kats is a must http://katriders.com/vb/showthread.php?t=116991 as it eliminates allot of silly wiring on the bike and puts the proper voltage direct to the coils from the battery

Don't ground them on Bolts man ground them on the lip of the plug hole.
Might not fix your issue but something to thing about
 
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No, neither of the coils are getting much power - when I cranked it and tested voltage into the coils it was 2v max.

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If your plugs aren't firing - you have to sort that out first then look fuel delivery issues. PM me if you need help.
 
if you already haven't ......

Quick Test Steps:

1.) key off................Normal 12.7 volts-12.9 volts

2.) key on (but not cranking with lights for 10 sec).....Normal 12.2-12.5 volts

3.) at idle (1500 rpm).....12.6volts - 13.2volts

4.) at 2500 rpm 13.5 -14.0 volts

5.) at 5000 rpm.....14.0 -15.0 volts

6.) key off.....slightly higher than measurements # 1 (12.8-13.0 v)

QUICK TEST Diagnosis Summary:

Basically Step #1 and #2 is making sure the battery is charged and in good health. The drop should be about 0.5 volts for normal headlamp and coil load (without cranking the starter). Anymore than 0.5V drop indicates the battery is weak even though the static voltage is OK (12.7-12.8V). If your battery is any lower it can have an effect on your charging voltages as the charging system only has so much capacity and will be drug down by a poor battery.

Step #3 is get a baseline starting voltage. This will vary some depending upon your idle and the particular R/R you have. It could be lower than the off voltage or as you idle up it will increase to 13.0 v

Step #4 by the time you get to 2500 RPM you should have close to the maximum output voltage even if you have bad connections. You are not pushing as much current and this shows that the stator is likely good.

Step #5 by the voltage at 5000 RPM being higher than at 2500 RPM you have a pretty good indication that your connections are good. If the voltage at 5000 drops from 2500 you have bad connections. If you already checked the grounds then it is likely in the positive legs between R/R(+) and Battery (+) check fuse box and the large bullet connector to the battery. The voltage climbs above 15.0 V it is likely the R/R not regulating and is bad bad.

Step #6 If after running for a few seconds in a charging state the voltage to the battery should have risen a bit. If it is lower than where you started then you did not charge at all, Again this will vary some what depending upon how long you let the bike run.
Click to expand...





http://members.dslextreme.com/users/storagecliff/images/electrical_odd-n-ends.html#A17

10 - With the coil plug connectors disconnected, use an ohm meter and measure the resistance of both windings on each of the coils. Exact resistance measurements are not too important, but continuity of the windings close to the approximate resistance values given indicates that the coils are in good condition. It must be noted that it is possible for the coils to only show up a fault when at higher operating temperatures, but this does not happen frequently.
Ignition coil resistance:
Between the two HT plug caps of the same coil, secondary HT winding, approximately 30 - 35 K ohm
Between the orange/white and white on the first coil and orange/white and black/yellow on the second coil, primary winding, approximately 2-5 ohm. If this test is within limits you likely have two good coils
Click to expand...
 
Double check and triple check the battery voltage as well

I had an issue yesterday, rode the bike to work not a problem started up fine, at the end of the day went to start the bike nothing turned on when key was put in the on position, found the main fuse blown 30 amp, replaced it with the spare, bike started up, got home, after dinner went to check what was up, found the part of the harness that held this fuse was melted, so I replaced it with a inline fuse holder, put it all back together, and bike would not start, she cranked over and over but no start, I finally gave up, and left the battery on the trickle charger overnight,,,,,,this morning I turn the key and hit the start button and she fires right up.....low voltage in the battery, meant low voltage to the coils, meant a weak spark, caused the bike to turn over but not start....or so it appears at this moment....

I should listen to my own advice at times...LOL

now that I ran the battery down so far, I will have to get it checked out to make sure it's not pooched and that it won't hold a proper charge and will still work while under load....ohhh well
 
If I'm not mistaken I'm pretty sure one coil fires 1&4 and the other fires 2&3. I would be looking towards battery or ignition coil issues.
 
I trickle charged the battery and it didn't work, and then boosted and it still wouldn't fire. Will check battery voltage in a bit, but it should be fine. Probably just going to rewire everything.

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