1988 XR4 not charging

[Musclford]

Got a 88 XR4, Serial OB264749 - Lazer II - on Champ, 184 FishnSki

We had issues with keeping it running last season, (after sitting for years) so took it in to get the carbs rebuilt (they were pouring fuel out), the Merc Dealer ran through their diags and also said a switch box was bad as well, thus we replaced both of the switch boxes, all fuel lines / primer bulb replaced as they were deteriorating internally and carbs rebuilt.

The, dealer also suggested removing the idle stabilizer module and taking off the oil injection due to it's age - we now premix 50:1

It runs great WOT, but still has issues at idle occasionally, having to restart multiple times after stopping for awhile.

BTW, I mentioned the "drivability" issues merely because I'm wondering if the low voltage / lack of charging is causing other issues with running in general.

Took it out last year and this spring and it doesn't seem to be keeping the main batt full. After idling across lake yesterday (no wake lake) 1000-1200 rpms yesterday, and running only our aerator and graphs periodically, our new graphs show the voltage at the battery 11.4v -11.5v and that doesn't change if we reved it to 2k.

After a full charge prior to yesterdays 8 hours on the lake, today the battery voltage per my fluke is at 11.6v (not running) and the Garmin graph shows 11.3v ~ .3 volt dif, but that's irrelevant at this point. At least I have an indicator going forward to watch my voltage.

Before we started for the last time yesterday, you could tell it had hesitations on starting to crank.. luckily it didn't take much rotations to start.

So far, I've checked the rectifier and and it appears ok, no diode leakage and ours also has the regulator on top the engine.

Looking for next steps? Stator? Should I run it and check the A/C across the yellow stator wires?

Thx

[Musclford]

Welp, an update....

With Engine at 1000, I measured 11.5 v at battery. Measured across 2 yellow stator wires and 7.3-7.5 v AC. So I believe that is satisfactory....
I decided to see if the voltage regulator was bad, so I unplugged yellow wire from the reg on the top of engine, and immediately battery voltage started climbing.
Batt voltage climbed to 12v at 2K in matter of 30 secs and kept going... seems the regulator is bad and clipping the output.

So, here's my question? If many models don't have them, do I really need the regulator?

Couldn't I merely, just remove it?

Adding pics to hopefully help someone else.

[leonreno]

I would think without regulators you would end up eating up your batteries by overcharging them. Some motors without regulators don't put out that many amps and probably just enough current to keep the motor running and battery charged. Bigger motors put out enough current to not only run the motor and keep battery charged but extra current to keep your other electronics and pumps etc running. Without a regulator that current would. It be regulated and sent to battery. Then again I could be wrong, I'm no exprert on regulators.

Also, did your mechanic replace or just clean and rebuild your carbs?, wasn't clear reading it. I hope he just service me then and didn't actually replace them, that would be unnecessary.

[Musclford]

Yep, that first post was brutal after re-reading it.... :( I tried to clarify for others.... But yes, just rebuilt the carbs!

Thx and yes, since these "newer" models have a higher amperage charge, it makes sense that I should replace the regulator.

Question is, do i just try to find an OEM part or are their better options 29 yrs later :)

[Musclford]

Well, I've determined the oem part is no longer available at the dealer.

Oem Part # 88825A7 Voltage Regulator

It appears that there are aftermarkets which have a new rectifier and regulator all in one?

Suggestions or feedback welcome on what to do.
I don't necessarily want to spend 200+ on an EBAY oem that is discontinued
Does this regulator actually touch the water, I haven't pulled mine off yet, but see there are mounting plates which have studs?

[JOE54]

put a 9amp stator on it let er roll/ no reg to worry bout been there done that a bunch 398-5454a7p/n you will only have a 9amp charging system