1997 130hp buckslike misfire when over 3500 rpm

"I would do that. It will tel

"I would do that. It will tell you if the ignition problem has completely gone away, and since there is "no load" on the stator (no current flowing), no harm will come to the stator. Tape them up good....
And don't get caught out there with a dead battery!!! Take some jumper cables with you, maybe someone will be nice enough to jump you off if you need it."

I always have a spare battery

I always have a spare battery and cables in the boat. I will let you know what happens when I replace the regulator next weekend. Thanks.

The stator is not putting out

The stator is not putting out enough. It is not even close. Replace both stator and regulator. That is always the best way to go anyway. After rectifing 16 volts A/C you will not be able to charge even close to 14 volts.

"Hi Tony,

I figured that it

"Hi Tony,

I figured that it was very, very low, but if you do the math..

16v x 1.414 = 22v DC after rectification, and that is enough to regulate down to charge a 12v battery.

Now that is ASSUMING the rect is a full wave bridge, and ASSUMING that the AC wave output somewhat follows the math for a true SINE wave. This has been hit on a few times before on this site, but I don't think anyone has ever absolutely confirmed it.

If it were half wave rectified, you would have 16 x .707 = 11v dc. and that is NOT enough to charge at all.

Does ANYONE know exactly the circuitry of the rectifier used on V4s and V6s?

But, you are right, he will probably need a stator, but he CAN do it safely in two steps by doing the reg/rect first.

Someone? Anyone on here work for CDI or have an "in" there?"

"More info. Yesterday, as repo

"More info. Yesterday, as reported above, I tested the motor (just me in the boat - 18' Four Winns) with the yellow stator wires connected and disconnected. In both cases I didn't have the misfire/bucking I had previously - was able to open it to max rpms with no problem other than no charging. So today I disconnect the yellow stator wires and tape them up and load the boat with lots of gear and 4 people and it won't even get on plane before the motor does its violent/shaking thing. So does this tell me it is more than the regulator? The motor idles fine. But it misfires/bucks at higher rpms with a larger load in the boat. I assume if the power pack was bad the motor wouldn't start or at least not run well at any RPM? So that brings us back to the stator and flywheel. How common is it for both the charging and power coils to go bad at the same time? Plus, although I replaced the original OMC stator with a used CDI stator, I still have the same problems. So that would have to mean both stators have bad charging and power coils? Very confusing!"

"Yes very confusing. And not l

"Yes very confusing. And not likely both stators are bad. Get the charging system working right, and then go from there...

You should be able to run it with rect/reg disconnected.
Your motor has SLOW feature. If it overheats, it "shakes violently". Yet you say it is not hot?
Look up at Morton's post of 9-1-09 at 10:01 am.

Possible two diff. problems...
Maybe an intermittent defect in SLOW.
What is it Mort, the white/black wire from the port temp sensor? Can he just disconnect that and test/eliminate SLOW?

I know you are reading these posts...I hope you didn't get hit with that Indonesian earthquake... first thing I thought of was "Wonder if Morton's OK?""

You could do a running test on

You could do a running test on your yellow wires by hooking a car headlight to them!
It should be able to light one of them!
What I have found with stators that are run for an hour or more into a dead short will heat the coils until they short to ground on the inside of the coil where you cant see whats wrong.
there are 2 tests you can do
One is to take a test light and go from battery positive to one of the yellow wires.
It will not light unless one of the charge coils have shorted to ground.
The other test you have to remove the flywheel and then ground one yellow wire.
You then take a jumper clip and hook it to the other yellow wire.
Now hold a wrench close to each of the charge winding poles one at a time While scratching the positive battery post with your jumper clip.
You will see a good spark each time you scratch but your not going to hold it on there for more than a second at a time.
Every coil pole should pull the wrench to it with a good clunk.

"^^^^^^^^^^^^^

Exactly. Go

"^^^^^^^^^^^^^

Exactly. Good suggestions there, especially the "magnetize the stator with external power".
I am going to remember that one.

Those things are just too expensive to shotgun one to see if it fixes the problem..."

"It goes without saying that t

"It goes without saying that there are at least a couple of shorted diodes in the rectifier, maybe more. So there is a good chance the battery has been discharging through the rectifier into the stator, possibly even to ground. An excellent recipe for damaging the stator, kill circuit, ignition switch, power pack. If the ignition switch and kill switch are not the source of the bucking, it has to be the power pack. The regulator circuit in the pack is malfunctiong. This is a very difficult thing to diagnose, especially when it is intermittent. None of the diagnostic tests will uncover it. You just have to make an educated guess.

Running the engine with the yellow wires disconnected seems to have eliminated the battery charging coils in the stator, but it would be better to disconnect the rectifier completely, if you have not already tried that. The battery could possibly be shorting through the rectifier.

Magnetizing the stator with an external 12V source still will not tell you if there is any arcing going on in the windings when the engine is running."

I guess you could also hook an

I guess you could also hook an electric lawn mower up to the two yellow wires to check the stator output. Don't put your hands in the blade when you try this.

"I am going to use every tool

"I am going to use every tool at my disposal, even the very unorthodox ones, to test these expensive parts. You can discard the suggestions here if you want.
Now, for some reason, I feel like I need to go out and mow the yard....."

"I am by no means an expert -

"I am by no means an expert - but I have owned my V6 EV 1990 for a long time and experienced many of the same symptoms you are seeing. The SLOW circuitry can be very difficult to diagnose. I use my motor in salt water exclusively. I flush it with fresh water every time but apparently not long enough each time. I still had salt buildup that caused intermittent SLOW problems. Repeated flushing with Salt Away cured the problem. If you disconnect the heat sensors at the top of each head - you eliminate excess heat as a source of your dropping into SLOW Mode. Once you are sure heat is causing the problem you can work on the thermostats, salt etc. I ended up removing the varnatherms from inside the thermostats the motor seems to be much happier with them out. I haven't put them back in yet.

I recently have had what may be rectifier / regulator issues after a hard starting episode. I noticed possible AC on my electronics running with the batteries low. Charging the batteries fully seems to have chased the problem away. During the incident my batteries seemed to be charging and the Tach. was working.

I replaced the Stator once before years ago - it melted or oozed. I have had that harness diode problem. This will also cause intermittent SLOW symptoms also. I have fixed loose magnets in the fly wheel. These will really drive you crazy. Make sure they are a firmly glued down and not moving around in there. They are magnets so you really need to yank on them to see if the glue has failed. Hope this help lead to a solution for you."

Since the "Oh Boy" com

Since the "Oh Boy" comment 10 days ago the space shuttle went to the space station and is on its way back !

Maybe...weather may scrub the

Maybe...weather may scrub the landing.

Nope...landing just waived off

Nope...landing just waived off.....no landing at 7:05...maybe at 8:45 or so...

what is your point?

Lots of good ideas and help he

Lots of good ideas and help here. I hope to install a new regulator this weekend and see what happens. Besides the variety of symptoms making the diagnosis difficult it has been frustrating only being able to work on it on weekends. Hopefully I will have it fixed by the time the lake freezes up.

I guess Andrew's space shu

I guess Andrew's space shuttle comment is offered as a contrast to what we have accomplished in the same amount of time.

Nothing wrong with a little comic relief.

At least you guys (and girls) have a better sense of humor than my wife.

"Weekend update. Installed a n

"Weekend update. Installed a new regulator and the tach is working and it is now charging between 13-14 volts. But, I still have the intermittent ignition problem at higher (3-4000 rpms) where the motor shakes violently until I reduce the rpms. I checked the blocking diode using the ohmmeter. Switching the testing leads gives different readings as the manual says. I even ran the motor with the 6-pin(wire) temp/tach plug disconnected, assuming that would take the diode and temperature sensor SLOW system out of play. Still had the ignition problem. Also ran it with the temperature ports and Quick Start temp sensor disconnected. Same problem. Another factor – I am not sure Quick Start is working when the motor is cold. It does seem (usually) to run the motor at 1100 rpms for 5 seconds, as it is supposed to when starting a warm engine, but I often have to use the manual throttle override during initial warmup. I am thinking maybe the powerpack is bad. It controls a lot of the ignition functions and the SLOW and QuickStart systems. Your thoughts and recommendations are appreciated."

"Highly unlikley its the pack,

"Highly unlikley its the pack, Hopefully one of the pros will explain TIMER BASE and its role on the engine.."

HI John I was woumdering if yo

HI John I was woumdering if you ever fixed you problems as I have a 1996 130 that lost spark on the bottom 2 cyls and I have been waiting for your solition. I have had soo much trouble with this motor over the years that Im probly going to get a new one. I hate to get rid of it because when it works its a very good motor but Ive grown to distrust it. I cant be 10 miles offshore when it decides to have a hissey fit. Please let me know how you make out. Thanks Lee

"Hi Lee,
Wasn't able to g

"Hi Lee,
Wasn't able to get to the lake last weekend. I am going to install a new powerpack this weekend and will report back.
John"

"IT'S FIXED!!
Turns out t

"IT'S FIXED!!
Turns out there were two bad parts. Previously, I replaced the regulator (see above). And the charging system and tach started working. But, I still had the intermittent ignition bucking at higher RPMs. This weekend I replaced the power pack and all the other problems disappeared. Quickstart is working again and no more bucking at high RPMs. Thanks to all for helping work thru this. Your thoughts and recommendations were very helpful."