gs550 will not start

[Fishman]

I apologize for a possible dumb question, but I need some validation on where to go from here. I bought an old, non-running GS550t that was in at best ok shape. I rebuilt my carbs (correctly, with new orings using the instructions on the site) and bought new carb boots and orings. I did not change out my petcock and that may be part of my problem. However, with a new battery and starting fluid, I can't get a hiccup out of the motor, it just cranks and cranks, occasionally backfiring. I have a clear gas line from the small petcock fitting to the #2 carb, and a regular fuel line from the big fitting on the petcock to the fuel "t". I see no gas in the clear tube, even with the petcock set on prime.

I am planning on changing out the plugs when I get home and checking for spark. I read about the weakness in the Suzuki charging system, but that shouldn't prevent it from starting, should it? Again, I'm a novice wannabe motorbike mechanic who's been having a great time working on the bike, but I need some success for once. I've searched for the answer on the site, but I've not found anything about this. Does anyone have some suggestions?

I plan on purchasing a new petcock, a Honda R/R and possibly some Dyna coils. Other than that, what next?

[Schweisshund]

hmmmm, mine was doing all of the described until I checked the stator. Make sure the pos and neg's are not touching each other via solder points.

[doctorgonzo]

After fuel, next in line would be spark I would think, so look there. On an old bike caps, plugs, wires, voltage drop to coils, any number of things could be going on.

[doctorgonzo]

Oh, and the clear line is vacuum, so you won't see fuel there.

[Schweisshund]

your fuel petcock may also be gummed up from gas evaporating. It turns into a buble gum type of varnish and could be blocking fuel.

Take it apart very carefully and clean.

[Nessism]

As doctorgonzo said, sounds like an ignition problem. Take a known good plug, install it into the socket and lay on the side of the engine while cranking - you should see a nice fat spark. The coils fire 2-3 and 1-4 together in pairs so check each one incase you have a bad plug. And don't forget to prime the carbs to make sure they are full of gas (set petcock to Prime to fill the float bowls and then turn it back to On or Res).

Good luck.

[Fishman]

Well it was raining like heck yesterday and I couldn't do much more than check to see if there was fuel in carb bowl #1 and there was. I will check spark tonight.

So am I understanding correctly that if the stator or the voltage regulator is out, the bike will still crank but not fire?

[Fishman]

Oh, and Nessism, your 550t looks gorgeous. I'm sorry you decided to sell it.

[Nessism]

Well it was raining like heck yesterday and I couldn't do much more than check to see if there was fuel in carb bowl #1 and there was. I will check spark tonight.

So am I understanding correctly that if the stator or the voltage regulator is out, the bike will still crank but not fire?

No. Stator and R/R are for charging the battery, the bike will crank and run just fine without these parts on the bike as long as the battery is charged. One noteworthy issue is when the R/R fails it allows the stator to over charge the system, which cooks the battery and could damage other electrical system parts because of an over volt condition. Hopefully this did not happen on your bike.

[Steve]

I am surprised that nobody has mentioned it yet, but one of the classic problems that prevents starting a cold engine is VALVE ADJUSTMENT. :shock:

Dollars to doughnuts, your valves are too tight. It's not hard to adjust them, there is plenty of information on the board (if you do a search) or you can just go to BassCliff's 'little' website and take a look at his tutorial. If you send me an e-mail (not a PM), I will get you a copy of my valve adjust spreadsheet that will help you with the calculations to help determine what shim you need to change to.

.

[Fishman]

Well, I got home last night and had a bunch of stuff to do, you know, the kind of stuff that you have to do when all you want to do is do what you want. Finally, the bike barn's faint calls could not be ignored and I set to work on my Gs550. Pulled plug #4 and it was wet with fuel and had good spark. In fact, fuel sprayed out of it as soon as I cranked the motor. Pulled plug #1 and it had great spark. Hmmm.

I check everything over again, fuel to to the carbs, plug boots seated well, wait, what's this? One of the plug wires has a clear plastic label, and it is a "3". It is the wire going to the #4 plug. No, it can't be, it would be too easy. Besides, that wire is much longer than the #3 wire and it just looks like it's in the right spot. Oh well, I'll switch them, what could it hurt.

I push the starter button and the engine stumbles a little. Scarcely believing my ears, I apply the button again and the engine roars to life!\\/ I disengage the choke at it settles right in to idle, except it's at 3500 rpm.

What a feeling! It's been at least 10 years since the bike had ran and here it is, running, and I made that happen! For this mechanically sheltered boy from the midwest, that is a huge accomplishment.

I assume there is an adjustment on the carbs to lower the idle so I will check that this evening. Then there will be no stopping me! Oh yes, except for all that other stuff I have to do, like two jobs and a family.

Oh, and the GSR is awesome. I have only limited practical experience with carbs, and I seem to have successfully renewed the set which came with my bike, which were in terrible shape. I already have several questions I need answers for, but those can wait.

I still need to buy a new petcock, install the rear brake, replace the old chain and maybe the sprockets, check the valves, new tires, and the mufflers are rotted out. I also got a bunch of nicer parts from Mack on this site and I will be working on the cosmetics with some of those. So I have plenty to do to get the old girl on the road again.

[Nessism]

Your next task... clean the carbs properly and change the intake pipe o-rings (your high idle is due to an air leak).

http://www.thegsresources.com/gs_carbrebuild.htm

http://cycleorings.com/

[rafael garza]

similar issue

I have a 650 but my spark is very weak. I have 12v on the orange wire to the coil but not sure what the other is suppose to read?? im at a lost. i have info on how to setup relay to coils but not sure if thats what it needs.

[doctorgonzo]

I have a 650 but my spark is very weak. I have 12v on the orange wire to the coil but not sure what the other is suppose to read?? im at a lost. i have info on how to setup relay to coils but not sure if thats what it needs.

The other is negative so it won't read anything on a voltage test. If you have 12V at the coils (assuming the coils are good), then it's downstream... plug wire, plug cap, plug.

[rafael garza]

huh

what are plug caps.. sorry not fimilar with term