No crank, no spark gs550

[Fishman]

I can't get my bike to crank.

I was having problems with hitting a wall at 5k (that's another post) which the bike would not go past in gear. This is after dipping the carbs and synching them. I took the excellent advice I got here and checked the mechanical advance. It's fine, but I put a little graphite lube on it to be sure. Then I put in fresh plugs, trimmed the wires, and fired it up. It ran so smooth, but still had a wall around 5k that I couldn't get past. So I pulled the carbs and found that the slides were gummy and wouldn't slide freely. Eureka! A little cleanup and I would be back in business. After that I checked the airbox as best I could without removing it and it looked good. Filter sealing well and boots ok too. So I buttoned it all back up and got ready to take it on a test run, confident I'd found the problem. I hopped on the bike and pushed the starter button and . . .


Nothing! No click from the starter solenoid or anything. I pulled everything back off and checked that a wire hadn't been cut or damaged. Nothing. I pulled apart the on/off and starter switch to make sure it was functioning. Replaced switch with weathered original and still no start. So I bridged the relay and the bike will turn over, but there is no spark on the #4 plug. I was so frustrated I didn't check the others, but I suspect they are also dead, as the bike just cranks along with no attempt at catching. Keep in mind this was just 3 hours after I had started the bike several times with no problem.

This is very frustrating. The bike was starting so easily and I appeared to just be experiencing a fuel related problem. Now it's obviously something electrical. I don't think it's the solenoid because of the spark issue.

When the bike was running previously, I also checked battery voltage (12.6) and charging voltage (13.9). I dropped a battery tender on the battery overnight to top off the battery but still no joy, as I suspected.

I guess the ignitor might have gone bad. It is on the bottom of the airbox which was moved around when I pulled the carbs. This is so frustrating, because I thought I was a minute away from a good running bike, and then to have this happen. Not to mention that I just ordered sprockets, chain, and some dyna coils from Z1, and I'm getting ready to do the r/r replace. I thought by now I'd have a running bike to work on.

[Fishman]

Well this must be a toughy, since nobody has chipped in with some advice.

What about a Dyna S to go with my coils. Does it replace the ignitor? My bike is a 1981 gs550t and has the mechanical advance with the electronic ignition. Would this be a good thing to do anyway?

It can't be the r/r or the stator from what I've read. So what else could it be?

[Nessism]

The ignition system is different from the charging system; R/R is for charging and the ignitor is for the spark.

Pull a plug and check for spark by holding it against the engine while cranking the engine with the starter. Assuming there is no spark, go back and check your electrical connections since you removed the airbox. The Dyna S will work of course but it could just be an intermittent electrical contact.

Good luck.

[chef1366]

Check all the connections in the fuel tank area. I bet you pulled something loose removing/replacing tank.

[Fishman]

My first thought was also that I pulled something loose. I checked every connection I could find from the back of the bike to the front. I opened the headlight bucket as well, even though I hadn't even been in there that day. After checking them all, I checked them again, and again, and again. I unscrewed every possible grounding bolt or screw that I found and cleaned them before replacing them.

Thing is, I've pulled these carbs at least 6 times now, and it's getting really easy. I didn't do anything different and there never has been any wire that I had to watch out for.

Incidentally, the clutch switch on this bike was bad, so I bypassed it in the headlight bucket as described by someone on this site. That was done many months ago and it has worked fine ever since. So that switch can be ruled out.

I didn't get spark on #4 grounded against the engine. I triple checked it to be sure and I couldn't see any spark. That was with the key in the on position, switch to on position, and screwdriver across the starter solenoid contacts. If the solenoid was all that was bad, it's obvious to me that there should still be a spark, right? Buttoned up, the engine would just turn over but never fire.

One question, if the ignitor goes out, can the bike just refuse to turn over? It seems to me that the causes of no crank and no spark would be very limited, particularly if it happened all at once.

I'll go check the wires again when I'm through being p----ed off about this. I really have enjoyed the work to bring this bike back from the scrapyard, but I've been working on it of and on for months. It's time to ride it. The new tires are in the bike barn, chain and sprockets on the way. Geez, I just need to catch a break on this one.

[Thomas Kenny]

Fishman, I feel your pain. Have you checked your voltage at the coils with the key on??? My voltage was dropping due to old wire harness, and I installed a relay and wired my coils direct to the battery for a good strong spark. Just a thought, although it sounds like you have a poor ground or something is not plugged in good since it just happened without you touching the wiring. Check for spark at all four plugs. Is it turning over briskly? If not try to bump start it, you may have a starter that is going south and is drawing a lot of voltage/amperage. Just rambling but hop you find it soon. If you have a good manual for your bike there should be a test procedure for testing your ignitor.

Regards,

[seekinsoul]

This may sound silly, but have you checked the kill switch to see if it's on or even working properly? It will stop the bike from turning over, and kill the spark. I've accidentally bumped it to the off position while working on my bikes, then going "What the...DOH!" when they won't turn over.

[chef1366]

Are you sure the ignition switch is good?

[Fishman]

I pulled out the old kill switch that I replaced a while back and re-installed it. No joy so I can rule out a bad kill switch.

I don't know how to test an ignition switch. The neutral and oil light comes on as normal, but that really doesn't prove anything. I would assume I'd need to pull the switch and test for continuity somehow. If someone has done this I'd like to hear how, otherwise I'm going to try and figure it out this evening.

I'm going to check my coil voltage if the switch tests good. I don't see how the coils would both go bad at once, but it may point to another part as the problem.

I should mention that I do have lights when the ignition switch is on. Also when I bridge the solenoid, it turns over very briskly. I don't think it's a starter issue.

Thanks for everyone's advice so far. I really appreciate it. My confidence has just been shaken a little, that's all.

[Fishman]

It turns out it was a bad starter button. I replaced with the parts from my spare and it works now. This bike is possessed.

Finally gave up on my original set of carbs because the bike wouldnt' rev past 5k rpm (see my post on it). Pulled them and put them on my bench. Spiffed up a spare set of carbs I picked up and then installed them. Interestingly enough, the bike now isn't getting any fuel. Even when turning my (brand @#$^%@^@#$ing new) petcock to prime, nothing comes out. I added a gallon of gas thinking that it might be down below reserve, but no joy. Set the tank right where I've been setting it all along throughout this project and it promptly rolled over and fell into the gravel, no doubt due to the extra weight of the fuel I put in it. Dinged it all up and scratched it.

So to review, bike wouldn't rev past 5k. Cleaned previous carbs and then it wouldn't crank. Finally determined it was the starter button. Fixed that. Still wouldnt' rev past 5k so I pulled the carbs and replaced with a different set. Now the new petcock doesn't appear to be delivering fuel. How can so many unrelated things go wrong on a bike at once?

Question: When I turn the petcock to prime, fuel should flow out, right?

[Nessism]

Question: When I turn the petcock to prime, fuel should flow out, right?

Yes, fuel should flow. Make sure the fuel tank vent is working properly and that the tank is not full of crud which is blocking the fuel - unlikely but possible.

Good luck.

[GQROD]

It turns out it was a bad starter button. I replaced with the parts from my spare and it works now. This bike is possessed.

Finally gave up on my original set of carbs because the bike wouldnt' rev past 5k rpm (see my post on it). Pulled them and put them on my bench. Spiffed up a spare set of carbs I picked up and then installed them. Interestingly enough, the bike now isn't getting any fuel. Even when turning my (brand @#$^%@^@#$ing new) petcock to prime, nothing comes out. I added a gallon of gas thinking that it might be down below reserve, but no joy. Set the tank right where I've been setting it all along throughout this project and it promptly rolled over and fell into the gravel, no doubt due to the extra weight of the fuel I put in it. Dinged it all up and scratched it.

So to review, bike wouldn't rev past 5k. Cleaned previous carbs and then it wouldn't crank. Finally determined it was the starter button. Fixed that. Still wouldnt' rev past 5k so I pulled the carbs and replaced with a different set. Now the new petcock doesn't appear to be delivering fuel. How can so many unrelated things go wrong on a bike at once?

Question: When I turn the petcock to prime, fuel should flow out, right?

Petcock should show a small stream of fuel when in prime.

When in run or reserve the amount of fuel should be much higher.

Putting a different set of carbs may give you a whole new set of headaches.

But if they are in better shape and you solve the rev problem you can take a look at your old carbs compare them to the ones you put on and see if there is something different.

Was the throttle cable adjusted properly? meaning the butterflies may not be completely open at WOT.

Do plug chops at 5000 rpm show lean or rich? Your mains may be clogged or incorrect size.

Also check for kinked vent tube hoses.

Hope this helps.

[Fishman]

Thanks to Nessism and GQROD for the petcock info. I checked and no fuel would flow from prime unless a vacuum was applied. Run position also flowed well with vacuum. Found that the carb set I installed had a small silicon plug in the vacuum tube on the #2 carb! I guess the previous owner was running a pingel. Anyway, after removing the silicon, I applied vacuum to fill the carb bowls and it fired up! Took it out and ran it up to 9k rpm in 2nd gear with no hesitation! Didn't pursue further until I get the new sprockets, chain, and tires installed. I'll check the synch, but I think I'm in good shape!

Sometimes it's the smallest things and it drives me crazy. Best to step away and get some advice and do some thinking and it usually works out.

GQROD, the main jets on my original carb rack were #95, whereas the Suzuki manual specs #92.5. The jets in the other rack are #105. My original rack also had two broken float posts that I repaired by welding and they were pretty rough all around too. The new rack is in great shape and appears to have been rebuilt with new orings, etc. The main jets are definitely new.

I guess larger main jets might be a good thing because the baffles on my replacement exhaust are certainly not in like new shape. I don't think that was my problem on the original carb rack because choking when bogging had no effect.

[chef1366]

I bet that was a "DOHHH!" moment!

[Fishman]

"I bet that was a "DOHHH!" moment!"

You are correct sir! Really relieved right now though. New sprockets, chain, and tires will be installed Saturday. Getting close!