Author Topic: ZG1000 1997: Bike dies after being ridden for a while (hour or so) (Read 1351 times)

Satyir · « **on:** August 15, 2018, 07:25:32 pm »

Hello everyone,

I've been getting ready for a couple long days driving to go visit a friend about 600 mi away. So, Changed oil, final oil, clutch fluid (needed it, badly), and other basic maintenance.
The problem for the past week is that when I take the ol' Bugeater out, she'll run fine on highway and county roads, but after an hour or so, if I end up stopping (either in traffic due to construction or at a stop sign) she dies. After about 3-5 minutes, she starts right up again, usually stays going long enough to get her home. I'm super stumped. Any clues?

Thanks!

Harry Martin · « **Reply #1 on:** August 15, 2018, 07:55:46 pm »

Can you supply more info?

Shortly after getting my C10, it would die after a long ride cause the J-Box had issues. After it cooled down, it would fire right back up. Reflowing the cracked relay solder connections fixed my problems.

Satyir · « **Reply #2 on:** August 15, 2018, 07:57:56 pm »

I got a new J box about 5 years ago, from that guy in FLA.
I also have a new starter from the same time period (while trying to figure out a non-starting issue)

Edit: Also, idles fine, about 1100 rpm, coolant system is great, never gets above 1/4 on the temp gauge.

Stasch · « **Reply #3 on:** August 15, 2018, 08:22:00 pm »

You may be having vacuum lock buildup in the tank. If you open the gas cap after such a stall, do you hear air whooshing into the cap, relieving the vacuum?

Or: are you running an inline filter between the petcock and carb feed?

If so, are you using clear tygon fuel line, and is it bent 90 degrees to turn down to the carb fuel connection at the bottom of carbs 2 and 3?

In the right conditions such as you describe, the tubing can heat up enough to kink at the bend, cutting off fuel flow.

After it cools a bit, or when you get home and take the tank off, its back to normal, and can be a bugger to figure out if you don't know what to look for.

I had the same thing years ago. A new Napa 3006 fuel filter (or equivalent) with a 90 degree connection turn on the carb side connection solved it. That filter configuration allows a fairly straight run for the fuel line on both sides of the filter.

Satyir · « **Reply #4 on:** August 15, 2018, 08:32:45 pm »

Huh, I'll check that out: I haven't installed a fuel filter, but the line could be bent.
Thanks

Oldschool · « **Reply #5 on:** August 15, 2018, 09:35:05 pm »

As best as you can go through the 3 things you need to make it run.

Fuel, spark, compression.

At the time it stalls, if possible, run through these one at a time. Spark is easiest, then fuel, then compression.

Identify which one s missing.

Victor Salisbury · « **Reply #6 on:** August 16, 2018, 09:23:23 am »

Check battery connections on the battery for tightness

Stasch · « **Reply #7 on:** August 16, 2018, 10:15:57 am »

Quote

but after an hour or so, if I end up stopping (either in traffic due to construction or at a stop sign) she dies.

Can you clarify what 'dies' means?

Is it a sudden stop like someone turned the key off, or does it starve out like its run out of fuel?

Steve in Sunny Fla · « **Reply #8 on:** August 16, 2018, 11:40:19 am »

While at first thought I'm right in line with Stasch's line of reasoning of a fuel starvation, usually that happens while riding, not when you stop. Since dropping rpm's is involved, I start thinking things like :

1) is the idle set to 1100 rpm? if it's to low it can stall;
2) when was the last valve adjustment? Tight valves get worse when the engine is warmed up, and the loss of compression means no power to idle.

HTH, Steve

Satyir · « **Reply #9 on:** August 16, 2018, 02:08:25 pm »

Stache- it dies as if the key's been turned off. -edit: now that I think about it more, it dies quickly, but sometimes with a "harumph"- like cough

FL Steve- I haven't checked the valves, yet. I was planning on leaving tomorrow morning for my trip- if I can make it to my friend's house- he's got a fully stocked garage...

.... hmmmm Also, checked the fuel line- no sharp bends. However: I found two loose connectors on the.... alternator.... ? What are the cylinder-shaped things directly under the fuel tank? I think they're the alternator... anyhow- those connectors were practically off, so I tightened them up. Also, hydraulic/brake fluid was low. topped that off too.

Again, she starts fine. If these thunderstorms pass I'll take her for another drive.

Thanks again for everyone's help

Stasch · « **Reply #10 on:** August 16, 2018, 03:42:08 pm »

Quote

What are the cylinder-shaped things directly under the fuel tank? I think they're the alternator... anyhow- those connectors were practically off

If it dies quickly its probably not fuel related.

Those cylinder shaped things are the coils.

If the electrical blade connectors were loose on those, you may have found your issue.

Steve in Sunny Fla · « **Reply #11 on:** August 16, 2018, 05:24:00 pm »

This does not sound like a bike that's ready for a trip. Just sayin'. Steve

Satyir · « **Reply #12 on:** August 16, 2018, 07:07:45 pm »

Yeah... if it happens on today's test ride, I'm going to end up taking the car

Satyir · « **Reply #13 on:** August 16, 2018, 08:48:15 pm »

Today's test ride: same result... Stalled at the off ramp, waited a minute, started right up again.

The ride is mostly 55 with some 25mph turns, then the last 20 minutes is on the expressway- throughout the country roads, I had no problems. After taking the freeway (70mph-80) she stalls at the stop (I take this exit when trouble shooting because it isn't used much). There is no vacuum problem with the gas tank (no air intake when I open the cap). Turns over when I hit the starter, but doesn't catch.

So, my trip this week is in the car, and I'll start hitting this problem again when I get back in about 10 days...

Cal · « **Reply #14 on:** August 17, 2018, 11:49:20 am »

OEM petcock? give the same ride a try with the petcock set on prime all the time.

Cal

MAN OF BLUES · « **Reply #15 on:** August 17, 2018, 08:47:37 pm »

Quote from: Cal on August 17, 2018, 11:49:20 am

OEM petcock? give the same ride a try with the petcock set on prime all the time.

Cal

while I never suggest riding on 'prime', or even setting it to 'prime' for longer than a moment or 2 to get fuel to the carb bowls, you comment does have some merit...

I'd suggest examining CLOSELY the vacume line from the caarb, to the petcock, for any signs of degradation, i.e., Cracks, or poor connection... pull the line off, and flex the ends, if it's cracked, you will notice them... OEM petcocks do function well for the mostpart, but a loss of vacume on that line, will shut off the fuel flow...
a free and harmless safe check, as opposed to running for any length of time on prime.

RWulf · « **Reply #16 on:** August 18, 2018, 01:07:36 pm »

Satyir, when you get back you might start thing about the ignition pickup.
There have been a few, not a lot, just a few that have failed after they get
warmed up. A real PITA to trouble shoot.

Bob_C_CT · « **Reply #17 on:** August 19, 2018, 12:54:01 pm »

Bike dies after an hour or so when you come to a stop, cranks but doesn’t fire, wait a few minutes and it fires up.

I was thinking pickup coil after it gets hot but I would think it would misfire a bit first and would take more than a few minutes to start back up.

Did this start after you did the fluid changes and other maintenance? If so what other items did you work on, may be something you worked on or something close by.

I had too much fuel line after I changed mine out but it would die at highway speeds after it warmed up and let the line get a kink in it.

I like the idea of the vacuum line not pulling enough vacuum at idle rpms after the bike warms up, either because of hose cracks or kinking too.

Of course Steve’s idea of the valve adjustments needed may end up being the problem as he is one of the gurus but check easy stuff first.

Jerry R · « **Reply #18 on:** August 19, 2018, 05:19:58 pm »

One data point offered for your consideration. Some years ago I suffered an ignition pickup failure and symptoms were exactly as you described. The motor would stop instantly as though the key were turned off, leading me to suspect an electrical rather than fuel problem. In the weeks it took me diagnose, the recovery time gradually got worse.

As RWulf points out, troubleshooting is some work. I added switches and indicator lights allowing me to bypass the ignition safety interlock circuit and monitor voltage at the coils, ignitor, etc., as I was driving and immediately after stoppage.

Replacement (used) pickup coils were the fix, and not expensive.

Jerry

MAN OF BLUES · « **Reply #19 on:** August 19, 2018, 09:31:26 pm »

I believe that SISF and I both share a common agreement, on when things go bad, with no warning...:
electrical problems may seem to be actually fuel issues...
and fuel issues, may seem to be electrical problems...

carry on.

Cal · « **Reply #20 on:** August 20, 2018, 01:54:31 am »

"while I never suggest riding on 'prime', or even setting it to 'prime' for longer than a moment or 2 to get fuel to the carb bowls, you comment does have some merit..."

yes - not asking him to ride all the time with the Prime position on. just wanted to get an additional data point without doing too much work (riding is hard at times!)

my thoughts were a possible loss of vacuum at lower RPM as well.

Cal

MAN OF BLUES · « **Reply #21 on:** August 20, 2018, 10:09:31 pm »

Quote from: Cal on August 20, 2018, 01:54:31 am

"while I never suggest riding on 'prime', or even setting it to 'prime' for longer than a moment or 2 to get fuel to the carb bowls, you comment does have some merit..."

yes - not asking him to ride all the time with the Prime position on. just wanted to get an additional data point without doing too much work (riding is hard at times!)

my thoughts were a possible loss of vacuum at lower RPM as well.

Cal

he did note this happens after about an hour on the freeway, I would assume he would make that run, and return,
I must have misread/misunderstood what you said in your posting.

Quote from: Cal on August 17, 2018, 11:49:20 am

OEM petcock? give the same ride a try with the petcock set on prime all the time.

Cal

I think I get it now, but it wasn't really clear,

let's wait and see, and hopefully he finds a bad vacuume hose, and repairs it, and we all sing khum-by-ahhhh

Steve in Sunny Fla · « **Reply #22 on:** August 22, 2018, 11:33:39 am »

Quote from: MAN OF BLUES on August 19, 2018, 09:31:26 pm

I believe that SISF and I both share a common agreement, on when things go bad, with no warning...:
electrical problems may seem to be actually fuel issues...
and fuel issues, may seem to be electrical problems...

carry on.

when the pickups go bad it's pretty much like carb issues. I remember about 30 years ago working on a dodge truck I'd rebuilt the engine and carb on. After about a month is was back with carb problems. The owner insisted it was carb problems. He was in his 50's I expect,, and I was in my late 20's, so I was more "malleable" then, and respectful of my elders. I didn't think it was the carb, but he insisted. Trying to satisfy him, I spent a lot of time working on the carb. It had plenty of fuel in the bowl when it would die out from "fuel starvation". Finally I told the customer that I was going to replace the ignition module. He was NOT going to approve the purchase, so I told him I would pay for it, and if it worked he would need to pay me 2X the cost of the module for the time I spent diagnosing . That would be an exorbitant total of 60.00. The module fixed the carb problem. He "didn't believe me" so he took the truck for a test drive before he paid me - and never came back. This is how I learned about ignitions emulating carb problems.

Steve

connie_rider · « **Reply #23 on:** August 22, 2018, 12:30:55 pm »

I've been watching this one, agree it might be electrical, but sure sounds like a fuel starvation problem.
ie; Sounds like fuel flow is restricted..

Ride safe, Ted

RWulf · « **Reply #24 on:** August 22, 2018, 02:52:33 pm »

I have allways maintained that the fuel in the carb do not all run dry at the same time.
When I here "the engine just stopped" I try to find out if it sputtered and stopped or
was it a clean stop. Of course if it's a single cylinder I would be wrong.