I remember this being discussed a few years ago.. Pretty sure it was before your time here.. I believe that "expert" said the amps while the car was running would or could do damage..

Bottom line Lynn.. Is it ok/safe to jump a atv from a car?

I have done it many times with no problems and even done it with no battery in my Jetmoto 150 and Yamoto 150..


1 time I watched a guy jump start his v8 van with his KTM 525.. he held the engine at the rev limiter for about a minute and sure enough the van started..

 

This makes no sense to me. Is this still in the archives somewhere? I'd be very interested in reading it if it is. I'm trying to think of any scenario where an excess of current capability would be catastrophic. I can't think of any.

Remember that car batteries output 12.6 volts, and quad batteries also output 12.6 volts. Car charging systems output 14 volts or so when the engine is running, and quad charging systems also output 14 volts or so when the engine is running. So far we have no differences. Everything on a quad is designed to run on 14 volts (+/- 0.5 volts) because that is what quad run on when everything is hunky dory.

I have a night light in the bathroom of my house. It consumes 7 watts of power (about 0.06 amps) from my local power company. The socket I have it plugged into can supply 15 amps of current (protected by circuit breaker). It doesn't draw anywhere near that much current. If I were to plug this little night light into a socket that can provide 30 amps it will not draw any more power than before. It still consumes 7 watts, and still draws 0.06 amps. If I were to climb the power pole and connect this little light to the main power company feed wires that feed my house it would still consume the same power and draw the same current.

It's the same when you connect your ATV battery to your your car battery via jumper cables. 12 volts is 12 volts. 14 volts is 14 volts. The current draw in your quad will be exactly the same. Excess current capacity at the input will *not* affect a working system at all.



Above we talked about a working quad being jumped to a car. Let's talk about failure modes, because you have to think about what happens if things on the quad are horribly wrong. Since you can draw a *lot* more current from a car battery than a quad battery is this more dangerous? Can the quad be damaged?

When you hook the car battery to your quad battery via jumper cables you suddenly have a lot more power available. But remember that your quad battery (assuming it is good) can put out 150 amps. Your car battery can put out much more. Is this a big deal?

The current from your car battery can go three different directions when it is jumpered directly to your quad battery:

1) From the battery positive post internally through the battery to the battery ground post.

2) From the battery positive post through the starter solenoid to the starter motor through some very hefty wires.

3) From the battery positive post through the main fuse into the wiring.

#1: If your battery is charged up there will be *no* current flow through your quad battery. They are at the same voltage, so the voltage difference is zero, and the current between them would be zero. No problem here. But let's say your battery is flat dead. Now there will be some significant current flow from the the car battery into the quad battery trying to charge the quad battery back up. Technically this can be little bad on the quad battery. Optimally you're not supposed to charge a dead battery this fast. It causes brief localized heating, and does take a little life out of the battery. But the same thing can be said about boost charging of you car battery with a charger that stuffs in 60 amps. Its a tradeoff. You trade getting your car started and taking off down the road versus waiting on hour on an "optimum" charging system (and paying for that time) versus overall battery life span.

#2: If this is your problem you will only notice problem when you push the start button. Then you will see hot wires, and maybe smoke. Of course if you were to do the same experiment with just a fully charged, good quad battery, you would see the same thing. It might take 7 seconds to start smoking the wires compared to 3 seconds with the car battery hooked up, but this is a difference that could maybe be noticed. But if your quad battery was completely dead there would be no smoke (or anything) with the quad battery, and lots of smoke with the car battery, and one might draw the wrong conclusion that the car battery thing was the cause - instead of the real fault whatever it might be...

#3: For some reason there are a lot of people out there who, out of macho stupidity or ignorance, have bypassed their main fuse with a wire, or, just wired in a new device and connected it directly to the battery. If you have a short in the wiring harness, or on an external device you have added, and it has no proper fuse protection, then you could have a problem. Again this will be a problem with a working fully charged quad battery, or a car battery jumped across. The only difference is the number of seconds to full blown flames.

If you have the proper fuse protection installed then a fully charged quad battery will blow the fuse in a few tens of milliseconds. A car battery jumped across will blow the fuse even faster (because the current is higher). Either way the wiring is protected.

 

i bought a new battery and connected it and the electric start wouldn't work i had to use a screw driver to jump the starter relay in order to get it to start, but not electrical things turned on.

 

what should i do?

i just installed the new recitifier but it didnt do anything

 

So if I understand your posts correctly, you can currently start up your quad by shorting across the solenoid posts. Am I correct?

If so then I think your problem now is that the ingnition/brake/starter interlock circuitry will not allow you to crank the starter over with the start button. Correct?

You've been buying a lot of parts and throwing them at this problem, yet I don't recall a single electrical measurement result ever being posted. Do you have a meter? If not, why? They're cheap compared to all the parts swap shotgunning you've been doing. It's not as hard as you think. You measure the voltage at the battery, then follow it to the ignition switch. Turn on the ignition switch and make sure you get switched 12 volts at the output side. Follow it to the brake switch. Then make sure the brake switch works. Follow it to the starter solenoid, and then to the start switch, etc. Help is available, but no one here has a crystal ball. It's time to stop guessing and start measuring . You have a wiring diagram, and that puts you at a big advantage over many other chinese quad owners...

There's another reason to consider getting a meter. You've just added a battery, and you need to make sure the charging system works. If it doesn't then you battery will slowly go dead and get ruined in the process. Batteries (even new ones) that don't get topped off and kept fully charged are quickly ruined. You need a meter for testing that. New batteries are much more expensive than meters...

 

i actually have a dmm and a brand new battery with a maintainer. im gonna try tomorrow to do some tests on the electronics.

 

well i'm getting a new starter relay in the mail so I'll be able to see if i fried it when i crossed the jump cables. my charging system is working when the quad is on it registers from around 12 to 13 volts.

 

Starter relays aren't damaged by reversed battery connections, so unless it was bad before you aren't going to fix the problem.

12 to 13 volts while the quad is on is not a valid test of the charging system. Rev the engine up to a medium fast speed (like 3000 RPM) with the headlights off. While the engine is at speed measure the battery voltage right on the battery terminals. You should see between 13.5 and 14.5 volts. If it less then that, or more than that, then your battery charging system is broken.

 

but then what else would cause the lights and other electronics to not work. the day my lights worked was the day i stalled a new coil. i wonder if it's still good. once the fuse blew i haven't had any electronics back, and i replaced the fuse.

 

I can think of lots of things - bad connectors, broken wires, and bad parts too - perhaps even the new ones you've thrown in there making the problem much more complicated than before because now you two (or more) problems. There is only one correctly wired up and functioning scenario to have a working quad, but the incorrect / non functioning scenarios are almost limitless.

I really doubt your coil is involved in this at all. There is no 12 volt anything going to your coil. In fact there is no 12 volt anything going to your whole ignition system.

To solve these types of problems you are going to have to use your meter and follow the wiring. Put your meter black lead on a good ground and leave it there. Take your red lead and start following the voltages:

1) 12 volts at the battery
2) 12 volts at the fuse input side
3) 12 volts at the fuse output side
4) 12 volts at the ignition switch input
5) switched 12 volts at the ingition switch output (switched on and off with the ignition switch)
6) 12 volts at the brake switch input side (ignition switch on)
7) 12 volts at the brake switch output side (when brakes are applied - also check to see if the brake light is lit up).
8) 12 volts at both sides of the starter solenoid small input wires (ignition on and brakes applied and brake light on).
9) One side of the solenoid input wires get grounded (goes to zero volts) when you push the start button.

This should not be a hard problem to solve. You just follow the wires with your meter. You have a wiring diagram. Yet for some reason, for reasons I can't begin to fathom, you refuse to do this. What can I say? You can lead a horse to water...

I'm pretty much done here unless you want to get with the program .