Voltage drop and lights dimming above idle. I'm stumped....

3361 Views 21 Replies 5 Participants Last post by TheBearAk, 19 d ago

DooDriver

Discussion Starter · Jan 18, 2021

Hello, I'm new to the forum and looking fwd to exploring all the info here!

I'm having a strange issue on my Formula 583 Deluxe. It initially started with a dead battery and a cooked voltage regulator.

I got a new battery and regulator and now anytime I go above idle, my lights go dim and the Tach stops working. Measured voltage at the lights goes from about 11v AC at idle and drops to about 7v AC.

I've tried the following to troubleshoot:

I've replaced the battery and I have tried 2 different voltage regulators without any change.
The lighting coil outputs 20v at idle and goes to over 40v at higher rpms...so the stator I'm thinking looks ok? I also measured the resistance at the coil and it's within spec for this model. I also didn't see any continuity between the AC output and the engine chassis.
I've even added a ground wire from the chassis to the engine in case there wasn't a good connection.
I've disconnected every harness under the handlebars I can find to see if something is causing a short. I haven't seen any difference in the behavior. I've also disconnected the entire hood harness and no change.
I've tested both new regulators as per the rmstator youtube video.....both appear to be in working order
If I test with the battery disconnected the voltage at the lights does the same thing...however the volts are about 6v at idle and drop to 3v when under throttle

I'm looking for some advice on what else to check. Both regulators have been Kimpex brand and I can't find OEM. But I can't imagine it's two bad regulators? What else could be causing the voltage to drop above idle?

Hoping someone has seen this before and can offer some additional advice...I'm stumped

Thanks in advance for your help!

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1 - 20 of 22 Posts

TheBearAk

· #2 · Jan 19, 2021

Is the Voltage Regulator well grounded? Does it have a metal case? The case needs to have a good solid connection to the frame.

DooDriver

Discussion Starter · #3 · Jan 19, 2021

TheBearAk said:
Is the Voltage Regulator well grounded? Does it have a metal case? The case needs to have a good solid connection to the frame.

Yes I even sanded the frame down behind the regulator.

When the sled is running I'm getting a couple volts ac if I put one lead on a yellow feed wire and the other to the engine chassis. I shouldn't be getting any voltage during this measurement should I because the AC system is not grounded?

kccats

· #4 · Jan 19, 2021

Welcome
Why did it fry reg?
Could you have a short?
Or bad stater

DooDriver

Discussion Starter · #5 · Jan 19, 2021

kccats said:
Welcome
Why did it fry reg?
Could you have a short?
Or bad stater

I'm not sure if the bad battery was caused by the reg or the reg killed the battery.

Everywhere I've looked I can't find a short but I'm worried there is a voltage leak back to the engine based on my tests.

Stator seems good? When disconnected from the regulator it puts out 20v at idle and goes up to at least 40v under throttle. I'm also getting 0.2ohms when I measure the lighting coil which is in skidoo spec.

DooDriver

Discussion Starter · #6 · Jan 23, 2021

I removed the seat and disconnected the back light and the fuel gauge and it didn't fix the problem.

I ran the sled without the voltage regulator and it works fine. I revved it up to 16v and didn't go any higher to burn the bulbs but the voltage kept increasing.

I can't imagine I have got two bad regulators though? I've reconfirmed I have a solid ground on it. It charges the DC side fine. But when it's plugged in the AC drops whenever I increase rpm above idle.

Let me know if you have any other suggestions.

Thanks

TheBearAk

· #7 · Jan 24, 2021

Maybe the yellow/Yel-Blk wires are backwards on the regulator?

I know that when I've seen 3rd party regulators connected backwards, it does exactly what you describe.

3rd party VRs usually just have different colors for the wires. Like Red, Black, Green, Yellow. Skidoo ones are Yellow-Yellow/BLK and with e-start they have a red wire.

DooDriver

Discussion Starter · #8 · Jan 24, 2021

TheBearAk said:
Maybe the yellow/Yel-Blk wires are backwards on the regulator?

I know that when I've seen 3rd party regulators connected backwards, it does exactly what you describe.

3rd party VRs usually just have different colors for the wires. Like Red, Black, Green, Yellow. Skidoo ones are Yellow-Yellow/BLK and with e-start they have a red wire.

Thanks. I will try swapping the yellows on the regulator and see what happens.

Given its AC I wouldn't have thought it would matter? But it's worth a shot. The regulators I've tried have a pre-asseembled harness so this would have happened from the factory.

DooDriver

Discussion Starter · #9 · Jan 24, 2021

I swapped the yellows on the regulator and the problem still exists. I did notice that the drop seems worse now and the voltage drops and lights dim if I just tap the throttle.

Before the wire swap I would have to give it slightly more throttle to see the behaviour.

I dunno. Could it be a second bad regulator? If the problem doesn't happen without the regulator I can't think of anything else. Even if there was a short in the system I should see a drop without the regulator but I don't.

kccats

· #10 · Jan 24, 2021

Try running a new separate ground wire from like recoil on motor to where the regulator bolts on.

DooDriver

Discussion Starter · #11 · Jan 25, 2021

kccats said:
Try running a new separate ground wire from like recoil on motor to where the regulator bolts on.

Ok I'll try that this week and report back.

Maineyak

· #12 · Mar 12, 2021

Has this issue been solved yet? I'm having the exact same problem on my 97 Grand Touring SE. My old regulator stopped working and voltage was too high, burned out headlight, etc. I got an aftermarket replacement, same exact issue as this, about 12v at idle with lights flickering, then voltage drops to 7 or 8v when you rev it up. Help!

DooDriver

Discussion Starter · #13 · Mar 12, 2021

Maineyak said:
Has this issue been solved yet? I'm having the exact same problem on my 97 Grand Touring SE. My old regulator stopped working and voltage was too high, burned out headlight, etc. I got an aftermarket replacement, same exact issue as this, about 12v at idle with lights flickering, then voltage drops to 7 or 8v when you rev it up. Help!

Yes even after tracing wires and adding/cleaning grounds I tried 2 different kimpex regulators and both had that issue. Found another brand of regulator and it fixed the issue for me. Seemed like faulty new regulators.

Maineyak

· #14 · Mar 12, 2021

DooDriver said:
Yes even after tracing wires and adding/cleaning grounds I tried 2 different kimpex regulators and both had that issue. Found another brand of regulator and it fixed the issue for me. Seemed like faulty new regulators.

Thanks for the quick response, that's so strange. I guess I better look into that then, thanks.

bweising

· #15 · 2 mo ago

Hello, I'm having the same exact issue on a 1998 Touring after changing out with a new after regulator. This is a shot in the dark on this old thread but I'm just trying to verify if both DooDriver and Maineyak both corrected there issue by trying multiple regulators? OEM regulators are no longer available.

kccats

· #16 · 2 mo ago

Welcome
For the most part adding a separate ground to the reg mount!

bweising

· #17 · 25 d ago

Any other comments regarding trying to verify if both DooDriver and Maineyak both corrected there issue by trying multiple regulators? OEM regulators are no longer available.

kccats

· #18 · 25 d ago

I have had issue with aftermarket regs
Just add an additional ground to it

TheBearAk

· #19 · 22 d ago

isolate: Don't hook up the DC pulse wire to the battery. Only connect the regulator up to the yellow/yellow-black wires and make sure it is grounded well. You can use a regulator out of just about any sled for testing. I keep an old Tundra/Citation regulator around for testing. Connect in parallel and check voltage while running.

bweising

· #20 · 20 d ago

Thank you BearAk. I believe you're suggesting to not hook up the Red Pulse wire to the battery? Do you cut or isolate the red wire at the regulator or the smaller red wire at the battery? If that's done doesn't that stop any charging of the battery?

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