Stalling at Idle does not restart

[Guest]

ON my 1982 GS550L I have been fighting with this problem.

It will start fine when cold, I will let it warm up for a minute and it will run fine, revs idles, but then the idle will drop and the bike will stall. After it stalls it does not restart.

If I give it 5-10 minutes it will restart and run again for another minute.

After it stalled I checked the compression and it has 130psi across the board. I also checked the plugs and they where golden brown.

I checked for spark and every plug sparked outside the bike, by holding the plug to the cylinder head. I did try a spark tester but couldn't get that to spark. But it didn't spark on a cold engine either.

This is really giving me a hard time.

Has anyone had these same problems?

I did adjust the valves when I got the bike. but with the compression I don't feel that is my problem.

I also tried running with it on prime and with the gas cap off no change. The only thing I did notice is that if I snap the throttle open when running it rev fine but then hang as it drops back to idle, probably has nothing to do with it but thought I would throw it out there.

The battery is fully charged and the stator is putting out 13.5V at idle.

Where should I look next.

Thanks guys for your help.

Curtis

[Steve]

If the idle hangs when revved, it's a sign of running lean on the pilot circuit.

Next time it dies on you, pull one of the drain plugs from a float bowl to see if there is any gas in there.

You have an external fuel filter in the line? If so, there is a good chance it's restricting the flow.

.

[curtie94]

I'll check that tonight. I'll also make sure I have no kinks in the fuel line.

[tom203]

Next time before you cold start it, put petcock in "pr" spot and leave it there - see if it still dies and won't restart.

[curtie94]

I'll try that as well. I was also told to spray the coils with water after it stalls and see if it will restart.

I noticed that the frame rail where the could mount gets hot while running I always just thought it was the engine that was warming it up.

[JTGS850GL]

Not likely it's the coils as both would not go bad at the same time and you pretty much ruled out no spark being the problem. If it's fuel it could be a pinched/kinked fuel line.

[curtie94]

So I re routed the fuel line. It isn't kinked.

I started and ran the bike on prime and it idled for 10-15 minutes before it stalled. Went to restart it and it started but I had the throttle wide open and it was at 900rpm the second I let off the throttle it stalled and now won't restart.

I'm thinking spark now. I cracked every bowl screw and they where all full. I tried ether and no good.

I think I'll see about getting some new coils. How do the coils ground though?

What is commonly wrong with the coils? The windings? Ground point?

Thanks again

[tom203]

"I think I'll see about getting some new coils. How do the coils ground though?
What is commonly wrong with the coils? The windings? Ground point?"

the primary winding grounds via the ignitor.
The secondary winding grounds from one spark plug to the other ,making the circuit
From what I've gathered on here, these ignition coils seem very durable.And besides you have spark during this no start episode, so I'm still thinking fuel problem. You sorta tested your petcock, but it might be flaky, so why not lose it altogether and feed fuel into fuel "t" thru auxiliary bottle. Yeah, I read the part about full fuel bowls, but call me skeptical!

[JTGS850GL]

Buying new coils is going to be a waste of money. If you think it's ignition then check for spark. While you're at it you might want to take a look at the plugs and see if they're wet or dry.

[curtie94]

plugs where dry but golden brown.

Even if it was fuel delivery from the petcock, If I filled the carbs after it stalled wouldn't it start back up?

Or is the engine overheating when it runs out of fuel?

[curtie94]

I noticed that my ignitor fuse was blown. But the PO had installed points instead. So I doubt that the fuse is my problem.

Tonight after work I'll install a new fuse and try again.

But like I said it still sparks.

I pulled cyl 1 bowl screw after it stalled and gas gushed out so it was full.

[curtie94]

I found that after it stalls if I spray starting fluid it will restart and run fine afterwards. But that is the only way it restarts.

Could it be one of the camshafts getting tight when it warms up. And it runs at higher rpm because of that.

If that was the case what would I have to do?

I'm really just thinking aloud right now.

[curtie94]

Could the bike just be overheating? I mean I am running it in garage.

I do have a fan on it but not a very good one.

Are these bikes prone to overheating.

[posplayr]

You should baseline the charging system before chasing this suspected electrical problem much further. What are your quick test results when cold then after your bike dies? Might give a clue. Low coil voltage can cause hard starting.

[curtie94]

I already installed a new stator and r&r.

But I noticed on cold idle I get 13.5v DC.

After it is warm it drops to about 13v.

But I did notice the voltage drops to about 12-12.5 when it stalls.