Yamaha Grizzly ATV Forum banner

1 - 20 of 56 Posts

·
Registered
Joined
·
31 Posts
Discussion Starter #1
Hi-
I am new to Grizzly Central and to this forum and this is my first post. I'm the guy in my neighborhood that gets volunteered or I volunteer to keep all thing internal combustion running or to get them breathing fire once again. I don't always ask for these missions or problems but I like to try and help considering that is my background and if it is a gift??? haha, or a God given talent to attract another headache!

From what I have been reading on this site, the Grizzly electrical systems seem to be riddled with many gremlins?! Here is my current Grizzly gremlin courtesy of one of my fine neighbors. 1998 Grizzly 600. It was running fine on Sunday and then just quit on him. With the plug out and plug cap removed from the lead I only get one spark to jump from the high voltage plug wire to the head when I let off of the start button. The battery is at just under 13 volts. I have not tried the pull start yet to see if I have a spark when using the pull start, I'll try that later today. I try to think simple because many times that is what it is something simple. The coil primary and secondary test fine and I am getting a reading on the red and white for the pulse / pick up coil. The start /stop button is working fine. Key switch on/off is fine but I did not disconnect it yet to isolate it from the system.

Thanks in advance for your help.....other opinions greatly help the troubleshooting process.

Thanks-
Joe Jr.
 

·
Premium Member
Joined
·
10,670 Posts
Welcome from Colorado.
It won't start with the plug remove :)
and many times a new plug fixes this problem.
I bet this old machine has never had the valve lash adjusted.
These low compression engines like everything with tolerance and if the valve lash is off from slightly stretched valve stems the plug can suddenly be fouled for no start. Many members have learned the plug might not look bad, and some have seen a spark, but the spark is not hot enough to fire the fuel.
So you let it turn over to test for start, when you pulled the plug was it wet?
 

·
Registered
Joined
·
31 Posts
Discussion Starter #3
Ridgeway81432-
Thanks for the reply. I'm trying to be polite here and maybe I wasn't clear enough in my post but if you have time re-read my post, you didn't read it you just scanned it, otherwise you would not have responded they way you did with information totally unrelated to what I wrote. The plug and plug cap are removed from the coil hi voltage coil wire to rule out the plug and cap as I already checked those when assembled and tried a new plug before removing the cap from the coil wire to check connection there and then to check the primary and secondary of the coil. You don't need to have the plug cap on the wire to check for spark. I noted in my post that I had the cap removed and was looking for the spark to jump from the lead to the head.
JoeJr
 

·
Premium Member
Joined
·
10,670 Posts
I missed the part of you using a new plug before your first post, and understood you took the cap off but didn't think you looked for spark without the plug.
Trying to be kind, as you have power to the coil(s), almost 13 volts with good amps to roll the engine with the start button confirming the battery is not weak, that the kill button is not the problem and the key works, I figured you needed a plug on the wire to look for spark first but that is now out as you did this.
Have you look into diagnosing the crank shaft position sensor?
 

·
Registered
Joined
·
5,545 Posts
What reading are you getting on the pulse coil? You must get a specific resister reading.
In the 600, the pulse coil resistance is 459 - 561 ohms

Spak plug cap resistance is 10 Kilo ohms

Ignition coil primary is 0.18 - 0.28 ohms
Ignition coil secondary is 6.32 - 9.48 kilo ohms.

Failed Pulse Coils are a common problem on the 600 Grizzly. I've replaced quite a few of them over the years. I would start there.
 

·
Registered
Joined
·
212 Posts
I'm assuming you mean "only spark once" while cranking over with the start button depressed.
I wouldn't check for spark without the spark plug cap, the spark plug attached, and grounded to the head/chassis. You could possibly damage the ignition system.
Spark plugs "spark" sometimes looks good but are not.
The first thing I would have done would be to replace the spark plug. If the problem continued then a shot of ether/starting fluid to determine whether it's a fuel or spark problem.

If it's an ignition problem,
dezz reply has good information.
ridgeway81432 reply "crankshaft position sensor is something to consider"
 

·
Registered
Joined
·
31 Posts
Discussion Starter #7
Hi-
No spark while cranking over with the electric starter. As soon as you let go of the electric starter button it throws one spark.
 

·
Registered
Joined
·
212 Posts
Okay.
If you havn't done this already, try with the spark plug cap, the spark plug attached, and grounded to the head/chassis. The ignition system might not function to protect from damage without the added resistance from these items in the circuit.
 

·
Registered
Joined
·
31 Posts
Discussion Starter #9
I have already done that. Only one spark when you let off of the electric start button.
 

·
Premium Member
Joined
·
7,922 Posts
Hey ...Joe Jr...Welcome to GC from Wisconsin.
While there maybe a chance the coil is bad. It seems that your coil is not getting the timed impulse to fire.
As dezz posted OHM the coil and impulse coil.
The impulse coil is the most likely issue it is part of the stator.

FYI: you will only find a CPS on fuel injected machines.
 

·
Registered
Joined
·
42 Posts
Use the recoil starter and pull it over slowly to see if it has normal spark at very low cranking speed. Slower than the starter. I suspect the CDI or kill switch is failing when it sees a higher voltage. Turning slower gives lower voltage.
 

·
Registered
Joined
·
31 Posts
Discussion Starter #12
Thanks to all for all the replies. The owner is getting it moved to my shop so I can dig into it a bit deeper with all my tools handy and to try some of your suggestions.......I do have a stick of dynamite just in case and a 6 pack of patience!
 

·
Registered
Joined
·
31 Posts
Discussion Starter #13
Ok.....this is what I have for numbers so far:
  • New NGK DPR8EA9 spark plug
  • Plug Cap is 10K ohms
  • Ign Coil primary is .3 to .4 ohms (bouncing) Should be between .18 to .28 ohms So I'm high there
  • Ign Coil secondary is 7.8K ohms Should be between 6.32K to 9.48K ohms So I'm good there
  • Pulse/pickup coil is 472 ohms Should be between 459 to 561 ohms So I'm good there
  • Source coil is 162 ohms Should be between 270 to 330 ohms So I'm low there
  • Source coil is putting out 34 volts ac when cranking with the electric start, almost the same 30 to 31 volts ac when pulling over with the pull start. Is that a good ac voltage output number?
  • Battery is at 13 volts and when using the electric start voltage drops to 11 volts
  • Will not, I repeat will not jump the gap with my spark tester (no spark at all) with the electric start or pull cord.
  • With the plug in the cap and grounded to the head I get one or two week sparks after I let off the start button and the same with the pull start just a few weak sparks.
What do you guys think? Is it the ignition coil or the source/stator coil???????
Thanks again in advance for all you help and feedback!
 

·
Registered
Joined
·
77 Posts
Hi check the voltage at the coil while cranking sound like hi current draw at starter may be robbing the ignition of power when you release the button power returns to ignition can be rubbed thru wiring harness or starter problem polling or brushes worn.
 

·
Registered
Joined
·
31 Posts
Discussion Starter #15
If that was the case wouldn't I have normal spark when using just the pull starter? Electric start or pull start I don't have proper spark. I will check voltage at the coil when cranking just to be certain.
 

·
Registered
Joined
·
77 Posts
Yes sorry forgot they have a recoil start on them only suggest tracing back the wiring from the coil to the CDI unit look for rub thru loom causing short or moisture getting in causing corrosion and hi resistance in the wire.
IMG_20191126_22266.jpg
 

·
Registered
Joined
·
31 Posts
Discussion Starter #17
Yes sorry forgot they have a recoil start on them only suggest tracing back the wiring from the coil to the CDI unit look for rub thru loom causing short or moisture getting in causing corrosion and hi resistance in the wire. View attachment 96794
I was hoping to avoid removing racks and bodywork but I'm probably going to have to so I can get to the wiring harness. Other than my 2 readings that are slightly out of spec. I want to check everything before ordering parts. Many Japanese service manuals like to state "compare to known good component" when referencing electrical components and numbers that are close to spec. I'm glad I volunteered for this job.....not!
 

·
Registered
Joined
·
77 Posts
Yes these thing try us out and people like us that put ourselves out there to help others are the one who gain the experience and knowledge from it let us know how you go .
 

·
Registered
Joined
·
31 Posts
Discussion Starter #19
Here's a little update. Turned the radio on in the garage to listen to the Superbowl while I worked on the Grizzly. I needed to pull the airbox and carb to check the pilot jet/circuit anyway so that gave me more access to much of the wiring from the stator to the connectors by the cdi unit and the reg/rec. I didn't see anything obvious but after moving the harness around a bit I now have a consistent spark. So I need to look closer at the harness to find out what is going on with a rub thru or broken but touching wire or wires under the exterior tape. Found another problem when removing the carb. The intake boot was torn completely in half and has been that way for a long time, so that needs to be replaced before I can go for the big startup try. I think the airbox and rear boot was holding the carb from falling off of the machine!
 

·
Registered
Joined
·
77 Posts
Glad to hear your making headway make you feel all warm and fuzzy inside Haha .
 
1 - 20 of 56 Posts
Top