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Main Area => General GS500 Discussion => Topic started by: Zilla500 on June 26, 2010, 07:46:07 AM

Title: Please help a dummy
Post by: Zilla500 on June 26, 2010, 07:46:07 AM
I went out to jump and start my 1991 GS500 yesterday, and the engine would turn but not start. I didn't realize I was running out of gas, and eventually did, but kept turning the engine. After a while, the engine won't even turn over anymore. Did I burn out my starter, or perhaps my coil? I'm about to troubleshoot it, base on the manual, but I could use an initial direction. Thanks! (Please don't laugh :)
Title: Re: Please help a dummy
Post by: Nber1LouFan on June 26, 2010, 08:09:59 AM
Quote from: Zilla500 on June 26, 2010, 07:46:07 AM
I went out to jump and start my 1991 GS500 yesterday, and the engine would turn but not start. I didn't realize I was running out of gas, and eventually did, but kept turning the engine. After a while, the engine won't even turn over anymore. Did I burn out my starter, or perhaps my coil? I'm about to troubleshoot it, base on the manual, but I could use an initial direction. Thanks! (Please don't laugh :)

ummmmm, is your battery dead? lol
Title: Re: Please help a dummy
Post by: Zilla500 on June 26, 2010, 08:35:13 AM
I see lights, so no. Also, like I said, this is happening "while" I'm jump starting it with another car running.
Title: Re: Please help a dummy
Post by: Homer on June 26, 2010, 08:53:36 AM
Here we go again...lol
Title: Re: Please help a dummy
Post by: Zilla500 on June 26, 2010, 09:03:53 AM
Yeah I read the forum before asking. In my case, I don't hear any clicks anymore, so I'm not even turning the starter. There can only be three issues with this correct? 1) Battery, 2) starter coil, 3) starter motor. Since I'm jump-starting it, 1) is eliminated. Since I see lights, 2) is eliminated. So that only leaves the starter? Is this correct logic?
Title: Re: Please help a dummy
Post by: ojstinson on June 26, 2010, 09:38:17 AM
Just a caution, Don't jump start your bike from a car with the engine running, the increased voltage from the car's alternator could cause severe damage to your electrical system----maybe that's your problem.
Title: Re: Please help a dummy
Post by: pandymai on June 26, 2010, 09:41:28 AM
check your fuses and hope they blew before anything else got fried from the excess current of the running car.
and yes, to reiterate, you shouldnt jump a bike with a RUNNING car, the car's battery alone should suffice in power.
Title: Re: Please help a dummy
Post by: Zilla500 on June 26, 2010, 09:52:01 AM
In the starter circuit, there's only one fuse, the one next to the starter coil, correct? That fuse is good since I see lights when I turn the key. Any other fuses that come into play when starting the bike?

I'll remember to not have a car running when I jump start next time. Thanks!
Title: Re: Please help a dummy
Post by: burning1 on June 26, 2010, 10:46:45 AM
Zilla, if you no longer hear a 'click,' it's possible that your starter relay is toast.

If I were you, I'd start by picking up your multi-meter and testing for voltage at the starter relay, the trigger lines from the starter switch, and the starter motor. Then I'd check resistance across the starter motor. Keep in mind that you shouldn't run the starter for more than 15 seconds at a time.
Title: Re: Please help a dummy
Post by: Homer on June 26, 2010, 11:01:51 AM
Don't even need to do that, actually.  Just jump the relay at the posts, bypassing the starter button/switch and the relay itself.  
Make sure it's in neutral, by the way...  (Which could be your problem, entirely....)
Just brush a heavy-gauge wire across the posts and listen.  

Edit:
if the starter doesn't bump over, then try tapping it with something.  Or unplug it from the relay and use jumpers.  Someone else will have to tell you which wires.  
If it's bad, ask SlimKlim to sell you the extra one I gave him.  
Title: Re: Please help a dummy
Post by: sledge on June 26, 2010, 11:51:52 AM
Starter motors and relays have an intermittent rating, they are designed to run/operate only for a few seconds at a time. If you have been letting the motor run and run without giving it a chance to cool down then yes.....its quite possible you have burnt it or the relay out. Get your nose on them, if there is a strong sweet and sickly smell then its fugged.

Its very unlikely the electrical system will have been fried by the donor battery because....
A) The voltages in both are the same ie 12v.
B) Despite the fact the donor battery/alternator can deliver far more current than the bike can the bike will ONLY DRAW as much current as it needs.



Title: Re: Please help a dummy
Post by: ojstinson on June 26, 2010, 01:16:05 PM
We are not talking about current here Sledge we are talking about voltage, a car's alternator can put out 16 volts or higher when charging, and this increased voltage will force more current through the bike's system than it is designed to take. Think of voltage as water Pressure on a hose, higher pressure = more water flow or current as it were.
Title: Re: Please help a dummy
Post by: Toledo Jim on June 26, 2010, 02:06:43 PM
Okay, an age old question:

Which way does voltage flow?  + to -,  or, - to + ?

Title: Re: Please help a dummy
Post by: sledge on June 26, 2010, 02:29:55 PM
2 things OJ

First I have never heard of a vehicle alternator delivering 16v, as far as I am aware the inbuilt voltage regulator every self-exciting alternator carries will limit voltage output to between about 13.5 and 14.8v to purposely prevent overcharging and the situation that you are suggesting might occur. However just because I have never heard of one that can output 16v it doesnt mean they dont exsist. Perhaps you could elaborate and provide me with some specs for such a thing.

On the subject can I ask you why if automobile electrical systems regularly see 16v (thats a 25% increase) it does not seem to harm the various bulbs and sensitive electronics they carry or cause the battery to overcharge?

Secondly with regard to your claim regarding an increase in current. Can I suggest you refresh yourself on Ohms law, particularly for current. You will find it states that in a DC circuit if power remains constant and voltage increases, current DECREASES, not as you claim increases.

Example:

Ohms law states Current (I) = Power (P)/Voltage (E) or I=PxV

So lets try the sums with a hypothetical load of say 100 Watts at both 12v and 16v

At 12v... P/V .....100/12.....= 8.3Amps

At 16V....P/V.......100/16......=6.25Amps

As you can see in the 16v circuit the current is lower by over 2A and from this it would seem to me you have something back to front in your sums.

Incidently this is the reason why some large comercial vehicles run 24v systems, it reduces current flow in the system, which in turn allows for thinner gauge wiring and smaller alternators which has cost and weight benefits.

It is true that components can be damaged by over large over-voltages, however, exposure to say 14.8v for the few minutes it takes to carry out a jump start is very unlikely to harm them.

Title: Re: Please help a dummy
Post by: ojstinson on June 26, 2010, 02:49:36 PM
AHHHH, free at last, now we can finally jump start our bikes from the car with the engine running without fear of damaging anything---I feel as though the weight of the world has been lifted from my shoulders.
Title: Re: Please help a dummy
Post by: Zilla500 on June 26, 2010, 04:10:03 PM
I suspected the starter relay first; I remember my 1995 Ford Explorer having an intermittent non-start/no-click issue and shorting the starter relay would alleviate the symptom. I hope it's this since it'll be a cheaper fix.I'll try to short it to see if it at least turns over.

I don't think the "jumping it with a running car" was the issue here. Oh yeah, it's in neutral - I'm not that kind of a dummy yet. :)
Title: Re: Please help a dummy
Post by: Zilla500 on June 26, 2010, 04:18:33 PM
Right after I typed my last reply, I went out and shorted the starter relay, and voila, starter turned over.Off to the internet shops! Thanks to all.
Title: Re: Please help a dummy
Post by: the mole on June 26, 2010, 05:12:21 PM
Quote from: ojstinson on June 26, 2010, 02:49:36 PM
AHHHH, free at last, now we can finally jump start our bikes from the car with the engine running without fear of damaging anything---I feel as though the weight of the world has been lifted from my shoulders.
Do I detect a note of sarcasm oj?
I can only agree with sledge on this issue. Every car, truck, bike, boat I've seen/worked on that has a 12volt system runs at a voltage of around 13.5-14.5 volts when the alternator/generator/regulator is in good shape. So, jumping your GS with a car that is running will have no detrimental effect on your electrical system if the donor vehicle's regulator is good.
Problems may arise, and might have in the OP's case, if you try to crank a reluctant engine for too long. With the standard GS battery this will likely result in a flat battery before too much harm is done to other components. With a jump start from a running car, you will likely fry the starter with too much cranking. You should definately rest the starter for a minute after 5-10 seconds of cranking to let it cool. During that time you can try to figure out why its not starting. If it doesn't start in 5-10 secs there is something wrong, no point burning out your starter as well.

I would like to point out that IF the donor vehicle's system is providing too many volts, then more current will flow through the starter, causing excess heat and possible failure.
Assuming the resistance of the load (starter) is essentially constant, V=IR, so if V is increased and R is unchanged, then I must increase proportionally. With more current (I) now flowing, P=VI shows that P is increased by the square of the increase in voltage. Note that this is an approximation, as R will change somewhat with current and temperature.
Looking at sledge's example, I think a better approximation would be:

With a nominal 100watt load,
At 12 volts:
I=P/V so I= 100/12, I=8.3 Amps.
V=IR, R=V/I, so R=12/8.3, R=1.45 ohms

At 16 volts:
V=IR, I=V/R so I=16/1.45, I=11amps
P=VI so P=16*11=177 watts

So going from 12 volts to 16 volts, the power has increased by about 75%.

Doing the numbers for 14 volts, the result is that P rises by about 35%.
That is why, if you're going to excessively crank a reluctant engine by jumping, its probably better to not have the donor vehicle running, but it will not have an adverse effect on your electrical system, which is designed to operate at 14+ volts.
Title: Re: Please help a dummy
Post by: Worm on June 26, 2010, 05:39:34 PM
I love the explanation sledge! So many people are worried about a car electrical system "forcing" it's high current on the bike and frying everything. I've read it in all of these posts about electrical problems. Thanks for the DC Circuit lesson for those who haven't had one!
Title: Re: Please help a dummy
Post by: ojstinson on June 26, 2010, 05:48:41 PM
Me? sarcastic?, perish the thought.

Think about it, do you really think anyone is going to jump start their bike with their car engine running after this---I stand by my statement about not using a running car to start your bike.


I think you and Sledge had better arm wrestle over the increased voltage- more current issue;

         You.
"IF the donor vehicle's system is providing too many volts, then more current will flow through the starter, causing excess heat and possible failure".

       Sledge.
"You will find it states that in a DC circuit if power remains constant and voltage increases, current DECREASES, not as you claim increases".



I'm so confused!



Title: Re: Please help a dummy
Post by: jeremy_nash on June 26, 2010, 07:07:33 PM
ok so  look at it this way, it most likely isn't going to hurt anything leaving the car running to boost the bike off, but a car battery has more than enough "juice" to start the bike, so why run the motor if there is even the slightest chance it may damage it?
Title: Re: Please help a dummy
Post by: TheRealSpinner on June 27, 2010, 12:37:20 AM
I wasn't going to get into this, but I agree with Jeremy.  Seems like you'd just be waisting gas by running the car, and right now, I need to save as much as possible.  So, next time my bike needs a jump, I'm gonna use the car battery to jump, but I'm not gonna start the car first, not because I am afraid of ruining the bike, but because I don't want to run the car.

I also don't take bags that I am offered (from stores) for things that I can hold in my hand(s), and I don't live in a house with rooms that I don't use every single day.  I'm funny like that, I try not to waste.  Sorry... rant over now.

-SPiNNeR-
Title: Re: Please help a dummy
Post by: the mole on June 27, 2010, 03:53:46 AM
Quote from: ojstinson on June 26, 2010, 05:48:41 PM
Me? sarcastic?, perish the thought.

Think about it, do you really think anyone is going to jump start their bike with their car engine running after this---I stand by my statement about not using a running car to start your bike.


I think you and Sledge had better arm wrestle over the increased voltage- more current issue;

         You.
"IF the donor vehicle's system is providing too many volts, then more current will flow through the starter, causing excess heat and possible failure".

       Sledge.
"You will find it states that in a DC circuit if power remains constant and voltage increases, current DECREASES, not as you claim increases".



I'm so confused!




OK, sledge has made an assumption that power is a constant, but I would disagree with that. In fact, the nearest thing to a constant is the resistance, which is just a physical characteristic of the thing being measured. It can vary a bit with temperature, but within a moderate voltage range it will not change much. Given that, then I stand by my analysis, and that's why I would agree that running the donor engine is more likely to overload the starter if you abuse it by overuse. However, as I said before, it will not affect any other components of the electrical system as the voltage when jumping is no more than when your bike is running normally.
Title: Re: Please help a dummy
Post by: Homer on June 27, 2010, 08:46:40 AM
Quote from: ojstinson on June 26, 2010, 05:48:41 PM
Think about it, do you really think anyone is going to jump start their bike with their car engine running after this---I stand by my statement about not using a running car to start your bike.

People hear what they want to hear. 

I've jumped a single-battery truck with 6-battery... let's say.. "heavier equipment", more times than I can remember.  With the donor turbine engine running at quite high rpm. 
(I'll let you wonder about the parallel vs series)
No blown starters, batteries, relays, or melted fuse boxes. 
If anything, it takes some of the scale off the anodes, like a deep-charge cycle. 

Mathematically?
Ohm's Law be d@mned.  The slightly increased amperage does next-to-nothing, it's why you're not using extremely tight tolerance fuses (which would blow if at high rpm, anyway).  The R/R does it's job, the wiring is stranded higher than it needs to be, and the battery can take it. 
A more important equation is the work being done by the starter motor, given higher current with constant coil winding.  The heat from 3 extra volts (GM alternator at max output) is irrelevant, especially on a starter bolted to an air-cooled engine. 

It's your exhaust bearings that you should worry about.   :icon_mrgreen:
Title: Re: Please help a dummy
Post by: ojstinson on June 27, 2010, 09:28:57 AM
Funny, I've been reading about not starting your bike from a running car on this forum for years and nary a peep, I say it once and electrical engineers start pouring out of the woodwork---I'm just glad I could be of assistance in finally putting to rest this old myth.

Here is a testimonial from Mary who has finally gotten closure on this issue.

"I love the explanation sledge! So many people are worried about a car electrical system "forcing" it's high current on the bike and frying everything. I've read it in all of these posts about electrical problems. Thanks for the DC Circuit lesson for those who haven't had one"!


And Homer;

"It's your exhaust bearings that you should worry about".

To be more specific it's the mufflers that have the bearings ( fore and aft ), straight pipes don't require them. And for you nautical people remember to always use "Relative Bearing" grease.
Title: Re: Please help a dummy
Post by: Homer on June 27, 2010, 10:31:09 AM
You're of assistance like a kid trying to barbecue. 
Takes too much time to explain, and the payoff isn't worth it.  Just keep the heat really low so you don't burn the bratwurst, and you'll still feel like a hero. 

















And, exhaust bearings are in the valvetrain, not the muffler. 
n00b.   :flipoff:
Title: Re: Please help a dummy
Post by: ojstinson on June 27, 2010, 10:37:51 AM
Nice try Homey, what a blistering comeback,  takes my breath away.

And by the way, while you're out pick up a sense of humour.
Title: Re: Please help a dummy
Post by: Homer on June 27, 2010, 10:46:53 AM
You're the one that can't figure out Ohm's Law, master of the dry wit. 
Title: Re: Please help a dummy
Post by: offcamber on June 27, 2010, 02:11:57 PM
I just use a portable jump pack.... :thumb:  :icon_lol:
Title: Re: Please help a dummy
Post by: marcusk on June 30, 2010, 04:28:04 AM
I'm with Sledge on this one.  But those of you that disagree next time you take your Play Station to your friends houses be careful in case they have a higher amperage transformer on there block you might force to much current into it and it will turn into a transformer (The kind that turn into cars. They are real you know) kill your wife and rape your dog.   I would be more worried about the GS spiking the ECU in your car and killing that. But with modern jumper leads that is highly unlikely also now they are almost all fitted with surge suppressors.. And if they're not you can overcome this by putting the negative side of the leads on the block or chassis.

Good luck fixing your bike Zilla
Title: Re: Please help a dummy
Post by: kman on June 30, 2010, 06:28:04 AM
If you do not have the car running the gs will try to charge the car battery as soon as the engine starts.  This might get tough on your charging system  since it will require more current the usual to charge your dead gs battery, plus u much larger battery.  You should leave the car running.  It won't take very long anyway so it won't be much gas.
Title: Re: Please help a dummy
Post by: Zilla500 on July 05, 2010, 01:28:26 PM
Got it running with a new starter solenoid from eBay ($30).

The electrical starting system has a 20A fuse which protects the bike.so I wasn't worried about harming it with the car running. I agree with kman's point on charging the car's battery once the bike starts if the car wasn't running. Higher potential energy, or voltage, always wins. Thanks!