GS550 won't start :(

[Anonymous]

Well, I fixed the run/off switch, and I got the starter switch to work, but it just turns over, like nothings going on. Its not even trying to start, or sputtering.

I cleaned out the carbs, thinking it could be the problem, ive done this before on different bikes, with success.. but when i put it all back together same thing, doesnt sputter, or seem like it fires at all.

So I check spark, and it was there, but it seemed weak. I dont really know what a strong spark should look like, but in daylight, this one was hard to see, and was really white. I think its supposed to be blue? All 4 cyclinders were firing, but "weakly" so I replaced all the plugs, hoping this was the problem.

Same thing, just turns over like nothings going on.

I boosted it with my car, when the car was running, and it turned over alot faster ofcourse, but all i got was a few LOUD bangs after a good while of turning it over that sounded like backfire. Still, the engine didnt even sound like it was firing. The backfire smelled like, I dunno... burning metal wires, or like a bottle rocket. Hard to describe, but it wasnt gas or anything.

Anyone have any ideas? It's getting kinda frusterating..

What would cause a weak spark?

BTW, its a 1984 Suzuki GS550ES with 10K miles on it, and its been sitting for a year or two.

[satchmo]

It was my understanding that a white, bluish-white spark wasn't weak. An orange one is weak.

What are the settings on your pilot screws at? Is it getting fuel to all the bowls?

How about compression? On my 77 550 I had this problem and it turned out to be low compression in a few cylinders

Satch

[earlfor]

Re: GS550 won't start

N E V E R !!!!!!!!! jump a bike with a running car!!!!!!!!!!!!!!!!!!!!!!!!!!!!

In all probability, you just cooked your stator, regulator/rectifier and ignition stystem, and probably your battery. Now, its no longer a question of getting the bike running, its a question of figuring out what is left that isnt destroyed. Sheesh!!!!!

The good news is a new stator is only $150, regulator/rectifier $120, ignitor box $450, crank sensors $100 and battery ...about $50, assorted wiring and fuses a few bucks.


Earl


[quote="jaykup"]
I boosted it with my car, when the car was running, and it turned over alot faster ofcourse, but all i got was a few LOUD bangs after a good while of turning it over that sounded like backfire. Still, the engine didnt even sound like it was firing. The backfire smelled like, I dunno... burning metal wires, or like a bottle rocket. Hard to describe, but it wasnt gas or anything.

[Anonymous]

Damnit. How Do I even go about checking if that stuff is bad? Ill have to do a compression test on it, I know I have it somewhere around here.

.. maybe the spark was orangish.. its hard to tell really

I thought it was OK to start it with a car if you only turned it over for 5 seconds?

The Rectifier was already bad

IF that stuff is still OK.. any other things I can check for why it wont start?

All the passages on the carb are cleaned out, and the screws on the top (adjustment ones) I didnt touch.. two years ago, the previous owner supposedly had it running just fine, drove it around til the rectifier/regulator went out. Then just let it sit.

I only had the car running a short time if it matters? Darn thing idles at 500 RPM's anyway (cars a pile too)

[Anonymous]

A lot of people would disagree, but I would try a shot of starting fluid in the breather inlet, under the seat, & in front of the battery. If it fires & trys to run a few seconds, You probably have carb or petcock problems, if it still doesn't even try to fire, probably an ign. problem. Be sure it is on full choke & don't turn the throttle at all.

[Billy Ricks]

I really need to put this all into a Word document so I don't have to do people's searches for them. It's all been posted dozens of times. Here I go again.

You can check your regulator/rectifier by following the Suzuki procedure below.

With the r/r removed from the bike, fins pointing up and terminals facing you, the terminals from left to right will be A, B, C, D, and E.
Negative probe on A and positive on B you should get 6-7.5 ohms.
Negative probe on A and positive on C you should get 6-7.5 ohms.
Negative probe on A and positive on D you should get 6-7.5 ohms.
Negative probe on A and positive on E you should get 50-70 ohms.

Then switch the negative probe to terminal B and place the positive probe on A, C, then D, you should get no reading. Positive on E should read 6-7.5 ohms.

Switch negative probe to C and positive to A, B, then D, you should get no reading. Positive on E should read 6-7.5 ohms.

Switch negative probe to D and positive to A, B, then C, you should get no reading. Positive on E should read 6-7.5 ohms.

Switch negative probe to E, positive to A, B, C, and D should give no reading.

Charging output test:
Start the engine and keep it running at 5000 rpm with the headlight on high beam. Measure the voltage at the battery. You should get between 13.5 and 15.5 volts. If not go to the next test.

AC generator no load test:
Disconnect the 3 leads from the alternator (stator) usually located under the gas tank. Start the engine and keep the revs at 5000 rpm. Using a multitester measure the AC voltage between the leads. When you do this check one against the other two. Do this for all 3 wires. You should get about 80VAC.

You should also do a continuity check. This can be done with the engine not running. Check each of the wires for continuity against the other two. This will tell you if any of the windings on the stator are broken. You can also check to see if the stator is shorting by checking each lead for continuity against a ground. If you get a signal when checking against a grounding point the stator is shorting.

Here's how to check the ignitor. Remove spark plugs 1 & 2 and ground them to the motor so they will fire when they get power. With the ignitor facing you, the plug on the right side of the ignitor is where the signal generator plug fits. The two terminals on the right side of that portion of the ignitor will be pin 1 at the front and pin 2 at the back. The two left pins will be pin 3 in front and pin 4 at the back. Turn the ignition switch on. With a multitester set a the X1 ohm range put the + probe on pin 2 and the - probe on pin 1. Plug number 1 should fire. Next put the + probe on pin 4 and the - probe on pin 3. Plug number 2 should fire. If this happens the ignitor is good and the signal generators are suspect.

As for testing the pickups, signal generators, measure the resistance between the two wires on each pickup. You should get somewhere around 130-200 ohms. If the resistance is infinity or less than spec they are shot.

To test the coils put one probe of the multitester on each of the terminals on the primary side of the coil. You should get 3-5 ohms. Check the secondary windings by placing one probe into each of the plug wires coming from one coil. Those would be 2 & 3 from one coil and 1 & 4 for the other. You should get 30-50,000 ohms for stock coils and 15-20,000 for aftermarket.

[Anonymous]

Thanks for looking that up for me, I'll test it all today in a little bit. As for the starting fluid, i was going to try that too, but If its getting enough gas, and no spark, shouldnt the plugs be wet? Ill try the starting fluid first, but I think ill try it right in the cyclinders, or take the air box off, and directlly into the carbs.

Ill test all of that stuff too, and let u guys know.

Thanks again.

EDIT: I was just thinking.. I dont know too much about carbs either... Are there any special lines that I forgot to hook up? THe only ones that I found connecting the carb to the bike, was the throttle, the two choke cables, and the gas line. there were two other rubber lines that i think were drainage, but im probably wrong, and then other one was the vacuum line that went to the gastank which i think is to operate the sort of "vacuum opearated fuel pump" the bikes have right on the tank.

[Billy Ricks]

The two lines dangling from under the tank are just vents. The vacuum line coming from the carbs is for the petcock. It is what makes fuel flow and stop depending on whether vacuum is present. Without it hooked up the only way the carbs will get fuel is with the petcock set to prime.

[Anonymous]

Ok, when i was trying to start it i did have it on prime (top setting) and wiht out the gas line on it, gas was comming out, so its not clogged. The carbs are getting fuel, and like i said, i did clean them all.

Im going out to test all the ignition components right now, ill let ya know.

[Billy Ricks]

Are all the vacuum fittings on the intake side of the carb plugged and the vacuum line connected?

[Anonymous]

There are two bolts on the carb where i think vacucm lines could be, and those are tight, if thats what you mean. The vaccum line that goes to the petcock its on on both sides, and the line looks ok.

I just did a test on the following:

Coil - Primary side was 5 ohms, and secondary was 35K, on both coils
Stator - I tested all 3 yellow leads to the ground, and there was nothing.
Rectifier/Regulator - Terminal "b" didnt respond to anything, all other readings were like 40-50 ohms. Im sure its shot.
Ignition unit - Gave a spark, on both coils, but very weak, at least i think so. My old Go-kart was more impressive. Last night it was easy to see, but with my sun glasses on in the day time, i couldnt see the spark at all, and just barly with them off.

I turned over the engine again (With the car off :\) and i got the same spark. The cyclider did smell like gas a little, but i was a little confused when the brand new plugs i put in where completely dry, they still looked brand new. If it wasnt sparking well, shouldnt they be a little blacker? or a little wet?

I guess im asking.. what would cause a weak spark? .. I think thats my problem.

Thanks again for putting up with me :\

[Billy Ricks]

Did you do a continuity check? You have to check each of the stator wires against the other two for continuity.

When you did the R/R test did you do it exactly as I wrote things? The probes have to be hooked up just like I posted paying attention to polarity. The only time you should get 50-70 ohms is when you check A against E. Negative on A and positive on each of the other three should yield 6-7.5 ohms.

As long as you got spark when you did the ignitor test all should be well there.

Did you do the signal generators? They are located under the small cover on the right of the engine.

[Anonymous]

I did do the Rectifier just the way you said, with the fins up, and the wires to me. I did pay attention to polarity too. Thats why it was weird that I got such high ohms. My Mulitester might be off though. The previous owner said the unit was bad anyway. As for the stator, Ill have to go back and do that test again, I'm looking for the wires to contact each other right? A good ohm reading?

Ill try out the signal generator too, and see if its any good. IF im getting spark when the engines turning over, shouldnt it all be OK then? Or would a faulty device cause a low spark?

[Anonymous]

Ok, I tested the Signal Generator under the cover (4 8mm bolts right?) and the leads were about 300 ohms, id have to say. It says to be 130-200, and if its LOWER then its shot.

I re-did the stator too, I got Full connections between all three of them, tested a-b b-c and a-c.

The ignition modual im having a problem with though.

"Remove spark plugs 1 & 2 and ground them to the motor so they will fire when they get power. With the ignitor facing you, the plug on the right side of the ignitor is where the signal generator plug fits. The two terminals on the right side of that portion of the ignitor will be pin 1 at the front and pin 2 at the back. "

I got the plugs off, and grounded to the engine block fins, and with the ignitor facing me, the right plug goes to the signal generator (its how i found it) Now, it says "the two terminals on the right side of that portion of the ignitor will be pin 1 at the front, and pin 2 at the back." Im assuming im supposed to pull the plug off first, weird thing is, there are only three wires going away from teh right plug, but there are four terminals. Pins 1 3 and 4 are all being used, but pin 2 isnt. Do i have a different set-up? The plugs didnt fire when i tried this, but pin 2 is pretty croded, yet it still fired when i turned it over with the starter.

I just thought, when i did this part of the test on the rectifier,

Negative probe on A and positive on B you should get 6-7.5 ohms.
Negative probe on A and positive on C you should get 6-7.5 ohms.
Negative probe on A and positive on D you should get 6-7.5 ohms.
Negative probe on A and positive on E you should get 50-70 ohms.

I was getting 50-70 ohms at the 6 - 7.5 ones, (I was on the Rx1 scale, which means whats on the display (analog) should be the ohm number)

I know I had the positives in the right place too. WIth the fins upright, and the wires facing me, the far left one was a black with a white strip, the negative im assuming. Ill double check though.

If it is really this much resistance, could that cause a low spark? Or am i just completely lost?

[Anonymous]

Im not sure if the 84 ES has it but did you hook up the engine breather hose? Its the hose that connects to the top of the valve cover to the air box. Not sure if you checked it, just throwing it out there.