PLEASE HELP!!!! 1984 GS550L starting problems (Earl around?)

[Anonymous]

Hey guy its me again. I bought a GS550L that had been sitting for about 3 years with no fuel in it at all, the tank had been custom painted and never reinstalled. I put a new ignitor box on mine as it had been stolen while it was sitting. The problem I am having now is that I can not get it to fire up. It turns over fine it actually backfired really loud and I found out the plugs wires were going to the wrong plugs. With the wires correct (1,4/2,3) the bike will turn over fine and is now putting out small puffs of black smoke while it is turning over out of both tailpipes (fuel problem?). The spark seems stronger on two cylinders than the other two. The airbox is fully installed and the battery is fully charged. It is an 84 model so it is electronic ignition. I tried starting fluid but it didn't help any. Any help on this problem would be greatly appreciated. I am hearby summoning Earl the GS GURU. 8)

 

[Anonymous]

Ok guys still working on it and it just backfired really bad again and shot about a foot long flame out the pipes. Anybody got any ideas???

 

[rodcwer]

SOUNDS LIKE YOUR PLUG WIRES ARE STILL OUT OF WACK.Also pull the plugs out and see if they are wet or balck and sooty if so clean and try again

 

[Anonymous]

Wired with the left coil going to 1 and 4 / right coil to 2 and 3. Brand new NGK plugs.

 

[rodcwer]

I have a 1000L and the left coilis 1 and 3 and the right is 2 and 4 .i am not sure if yours ids the same but you may want to check it

 

[earlfor]

I would first verify that the new ignitor box is working properly.
With the box disconnected, resistance between the yellow and blue wires should be between 100 and 300 ohms. Resistance between the black and green wires should be 100 to 300 ohms.
Reconnect the ignitor box.

Next, I would remove all the spark plugs and reinsert them in their caps.
Ground the plug threads to the cylinderhead.
Turn the starter motor and check that each spark plug sparks. The plugs are paired electrically 1,4 and 2,3. If either pair sparks weaker, then I would check the coils, Resistance between the + and - terminals on the coils (with the coils disconnected) should be between 2 and 5 ohms. Average is 3 to 4 ohms. Resistance between the spark plug caps should be between 30k and 50k ohms. If it is greater than that, you may need to replace a plug cap.

To check the ignitor, set your multimeter to the ohms X1 scale. Connect the meter + lead to the black terminal on the ignitor box. Connect the meter - lead to the green terminal on the ignitor. When the negative lead is disconnected, the 2,3 plugs should spark.

Connect the meter lead + to the yellow terminal of the ignitor. connect the meter lead - to the blue terminal of the ignitor. When the negative meter lead is disconnected, the 1,4 plugs should spark.

Let me know how this much goes and we will take it from there.

Earl

 

[KEITH KRAUSE]

I have a 1000L and the left coilis 1 and 3 and the right is 2 and 4 .i am not sure if yours ids the same but you may want to check it

Not so. One coil feeds 1 and 4, the other coil feeds 2 and 3.

 

[rodcwer]

I have a 1000L and the left coilis 1 and 3 and the right is 2 and 4 .i am not sure if yours ids the same but you may want to check it

Not so. One coil feeds 1 and 4, the other coil feeds 2 and 3.




your right I went out and checked I was looking at it wrong the other day.... my mistake forgive me

 

[Anonymous]

Ok. I have no multimeter so this is a little difficult to track down. I swapped the wires from one coil to the other and after and lot of cranking it finally fired up but is running like its only hitting on 2 cylinders. Each time it takes a lot of cranking to fire up and it has to have the throttle almost wide open to stay running but it is not revving dont get me wrong. You think one of my coils is not operating as efficiently as it is supposed to? Thanks for all the help guys.

 

[earlfor]

I have no way of helping you if I dont have the information of how the electrical/ignition system is working. for less than $10, you can get a multimeter at Home Depot or Lowes. Yes, something is surely not working correctly. Thats the problem. What, is the question.

Earl

Ok. I have no multimeter so this is a little difficult to track down. I swapped the wires from one coil to the other and after and lot of cranking it finally fired up but is running like its only hitting on 2 cylinders. Each time it takes a lot of cranking to fire up and it has to have the throttle almost wide open to stay running but it is not revving dont get me wrong. You think one of my coils is not operating as efficiently as it is supposed to? Thanks for all the help guys.

 

[KEITH KRAUSE]

You need to test the ignitor box as Earl said. But if you trust it because it's new and you have no tester, you don't have much choice. I hope the compression is good too.
Now that you're sure the leads are connected correctly, check the harness connections at the coils, the plug leads at the coils, and the plug caps. All connections must be solid and clean. Take a new or clean plug and inspect the spark quality. In a darker area, the spark should appear blue or blue-ish, and be fat. If it's yellow or orange and weak, the spark quality is poor. If it's good, go to the fuel system.
Make sure the vacuum line is in good shape. Check the flow of the petcock. Clean the gas cap vent.
Clean the carbs and check all o-rings and rubber parts. Inspect float levels. Bench synch the throttle valves. Make sure all vent lines are connected correctly and open.
Inspect the manifolds for good condition.
Clean/replace the air filter.
Just basic maintenance really. The bike's been sitting.
If it starts up and idles decent, vacuum synch the carbs.

 

[Anonymous]

Ok guys. Bought a multimeter today and checked the coils and they seemed ok. My ignitor box has two plugs that connect to it. One comes from the side of the engine (stator?) and has three wires 1 brown, 1 green wtih white piping, and 1 black with white piping. The other plug runs to the coils i guess. That plug has 2 black with white piping (coming out at the same spot), 1 black with yellow piping, 1 orange with white piping, and 1 solid white wire. How do i test this ignitor box and im guessing the stator? Thanks.

 

[earlfor]

The ignitior box is 12v DC powered. The stator puts out 240 volts in three phases of AC current. I can think of no reason why the stator would be run through the ignitor. The charging system is separate from the ignition system. The stator supplies AC currect to the R/R which rectifies it to DC to charge the battery. All systems on the bike operate on 12v DC from the battery.

Your ignitor color codes are different than mine. There should be a four plug/wire connector connecting your ignitior box to the harness. I will assume you have neither a service manual or a wiring diagram for your bike. Assuming you have the four wire connector that connects your ignitor to the wiring harness, the end should look something like

-------------------
- 1 2 -
- -
- 3 4 -
- -
--------------------

The top numbers (1 and 2) are positive meter lead connections.
The bottom numbers (3 and 4) are negative meter lead connections.
Cylinder pairs are vertical. to check spark on the 1,4 plugs, you put the positive meter lead on wire 1 and the negative meter lead on wire 3.
Removing the negative lead on wire 3 should make the plugs on the 1,4 cylinders spark

To check spark on cylinders 2 and 3, connect the poslitive meter lead to position 2 and the negative meter lead to position 4. Disconnecting the negative lead from terminal 4 should make spark plugs 2 and 3 spark.

Have you checked all four plugs for spark and intensity of spark? What did they look like? What battery voltage did you have when you made the check?

Earl

Ok guys. Bought a multimeter today and checked the coils and they seemed ok. My ignitor box has two plugs that connect to it. One comes from the side of the engine (stator?) and has three wires 1 brown, 1 green wtih white piping, and 1 black with white piping. The other plug runs to the coils i guess. That plug has 2 black with white piping (coming out at the same spot), 1 black with yellow piping, 1 orange with white piping, and 1 solid white wire. How do i test this ignitor box and im guessing the stator? Thanks.

 

[Anonymous]

Hey Earl the end of my ignitor box looks like this and the wires are like above.

__ ... __ .......... __ __
__ ... __ .......... __ __ two individual wire plugs plug into

this ingitor any ideas??? Sorry about the stator confussion I just dont know what the three wires running from the ignition (engine case) to the ignitor are for. Thanks for all of your help.

 

[earlfor]

We need a wiring diagram for an 84 550L. With two separate plugs and 8 connections, I will not risk a guess. Connecting the wrong thing could destroy the ignitor.

Earl

Hey Earl the end of my ignitor box looks like this and the wires are like above.

__ ... __ .......... __ __
__ ... __ .......... __ __ two individual wire plugs plug into

this ingitor any ideas??? Sorry about the stator confussion I just dont know what the three wires running from the ignition (engine case) to the ignitor are for. Thanks for all of your help.

 

[earlfor]

OK, after some head scratching, ................ the plug with three wires is from the crankshaft sensor/signal generator on the right end of the crank.

The remaining wires in the four wire plug go to the coils. You have two black with white piping, 1 black with yellow piping, 1 orange with white piping and 1 solid white. (thats 5 wires BTW on a 4 wire plug)
Unfortunately, of the dozen or so wiring diagrams I have for various GS models, none of them show 5 wires in those exact colors. I still need someone with a 84 550L diagram.

Earl

Ok guys. Bought a multimeter today and checked the coils and they seemed ok. My ignitor box has two plugs that connect to it. One comes from the side of the engine (stator?) and has three wires 1 brown, 1 green wtih white piping, and 1 black with white piping. The other plug runs to the coils i guess. That plug has 2 black with white piping (coming out at the same spot), 1 black with yellow piping, 1 orange with white piping, and 1 solid white wire. How do i test this ignitor box and im guessing the stator? Thanks.

 

[Anonymous]

I'm sure you've already thought of or looked at this, but maybe you haven't. bikebandit.com doesn't have an 84 550L as an option.

Here is the wiring harness diagram for the 84 550ese. It probably won't help, but just in case...

 

[earlfor]

Thats harness layout. Unfortunately, I need a schematic showing individual wires and their colors.

E.

I'm sure you've already thought of or looked at this, but maybe you haven't. bikebandit.com doesn't have an 84 550L as an option.

 

[Kabonkie]

Earl, looks like the same for an 83, except for the two wires fromt the same spot. Here is what the diagram says.
Four wire plug: White to coils, Orange /white to kill switch/starter button, Black/white to fuse panel, Yellow/Black to coils.
Three wire plug: All three to the pickup coil.

If you need to look at it, then I could scan it and e-mail it to you.

Hope this helps.

 

[earlfor]

Ok then, orange/white is normally a positive wire and the kill switch and starter circuit are + on the switched side so...........orange white is +.

Black and white to fuse panel. There are no negative leads off of the fuse panel that I know of. It would be 12+ power supply.

Yellow/black is normally neg to the right coil.

That leaves white, and it should be the neg for the left coil.

That would mean that to test the ignitor, if you put the multimeter probe + on the orange white and the probe neg on the white, disconnecting the neg probe should fire the 1,4 cylinders.

Putting the + probe on either the orange/white or the black and white and meter neg on the yellow/black should result in the 2,3 cylinders firing when the neg lead is disconnected.

The problem is this is an educated guess.

Before doing this, I would unplug the ignitor connector from the wiring harness and turn the ignition switch on. Take a multimeter and check the wire colors on the harness end to verify that + and negative wires are as I have guessed. If not, STOP.

Earl

Earl, looks like the same for an 83, except for the two wires fromt the same spot. Here is what the diagram says.
Four wire plug: White to coils, Orange /white to kill switch/starter button, Black/white to fuse panel, Yellow/Black to coils.
Three wire plug: All three to the pickup coil.

If you need to look at it, then I could scan it and e-mail it to you.

Hope this helps.