Low voltage when idling, any ideas??

[tmorefi]

When I am idling, my voltage is dropping down to the 10 range and then I lose all power. When I rev the RPM's, I can see the voltage go up to 13-14 like normal. I checked the alternator and it's all good and the batteries are fine, killed the stereo and same problem. Anybody seen this or have any ideas?

tony-

2003 SAN

[Timber]

That is weired man. I'm having the same problem. My volts go down to 11.2-11.5 when just trolling along. Above 1,500 rpms the boat does fine. I have an 05 with the stronger alt.
A friend of mine suggested that I put a smaller pulley on there, so it will make the alt. spin faster. I will be trying this with in the next week.

[tmorefi]

mine just started happening all of a sudden at shasta last weekend. i thought it could be the alternator and just had it bumped up to 130 amp, still happening though. the shop can't get me in right away so trying to trouble shoot myself. my other belt, not the alternator belt is loose, any reason it should be?

[Mikeski]

It's normal for the voltage to drop down to the 11.2-12.6 range when the motor is below 1500rpm since most alternators don't produce much current in this range, so Timber yours is acting normal. Some of the high amp alternators produce less current at low rpms then the standard alternators so this may be causing your problem Tony. However if the batteries are charged it should not drop down as low as Tony's. Remember most factory voltmeters are really just tell-tale meters that tell weather or not it's charging, the actual meter calibration is not accurate at all. If you have a perfect pass press the menu and up arrow sumultaneously for 5 seconds then scroll to battery voltage, it's much more accurate then the analog gauge.

I may go out to Discovery Bay tomorrow night or Saturday morning, let me know if you want me to bring a meter and test your charging system on the water.

mikeskiw@gmail.com

[tmorefi]

Thanks Mike. I actually upgraded to the higher amp alternator after the problem occured so we can rule that out. And, it's not actually the voltmeter on the boat that worries me, it's the fact that the big red LOW VOLTAGE light keep coming on and then my boat dies a few seconds/minutes later. I have a multimeter I am going to test my output on tonight as it's idling but I don't really know where to check if there is a big pull coming out someplace. So tonight I will be checking, cleaning, replacing, tightening both belts and checking my alternator output while idling and revving. Anything else I should try? call my cell if you have ideas. I'll be working on it. 408-398-9109. thanks, Tony-

[Mikeski]

Just spoke with Tony on the phone, He has a perko switch on his battery line so I suggested he measure the voltage drop across the switch, as most guys know these perko's can be a source of many problems.

more to come...

[tmorefi]

I FIXED IT!!! Thanks for the help Mike. While I was doing some of the testing you recommended, I noticed one of wires on te back of my on/off switch behind the throttle was disconnected. There are three wires going in and one was off. Plugged it in and problem resolved. Thanks again for the help guys. Mike, where you going on Saturday? Looks like we might be out there afterall....

[Timber]

Hey Tim,
There are a few of us heading out to the Delta on staurday. We should all meet at ski beach. Say around 2pm?
-Brian

[tmorefi]

Brian,

When you refer ski beach you're referring to one by union point not out by lost isle, right?

Tony-

[wakejunky]

I had a similiar problem that resulted in the boat cutting out at speed. Finally fixed it a few weeks ago and posted my solution here. The problem was low voltage to the dash, battery was at 12, dash was at 11.2. With all the accessories running off the 10g wiring from the battery, there just wasn't enough current to get up front. Perfect pass is a real current hog, not to mention the heater. Anyway, put in an extra 4g wire from battery to dash and walla, dash voltage = battery voltage.

Chris

[Timber]

Yes the one by union point. It is at the end of twin slues. I will be there around 2pm with a few other super air's :grin:

[bkhallpass]

Yes the one by union point. It is at the end of twin slues. I will be there around 2pm with a few other super air's :grin:

I'd like to catch up with you guys. However, I'm getting married
at DB Country Club at 4:00. I'm afraid the fiance might think that's
cutting it a little close. I'll have to catch up with the delta SANs some
time in July.

BKH

[skiswm]

Yes the one by union point. It is at the end of twin slues. I will be there around 2pm with a few other super air's :grin:

I'd like to catch up with you guys. However, I'm getting married
at DB Country Club at 4:00. I'm afraid the fiance might think that's
cutting it a little close. I'll have to catch up with the delta SANs some
time in July.

BKH

BKH best of luck and congrats on the wedding. At least you will have a view of the course there at Disco bay........and not the water.

[tmorefi]

I hope you're going riding in the morning before the wedding. I hit the water in tahoe the morning of my wedding and it was a great way to start off the day/rest of your life....

[bkhallpass]

I hope you're going riding in the morning before the wedding. I hit the water in tahoe the morning of my wedding and it was a great way to start off the day/rest of your life....

Golfing actually. Just me and the best man 7:30. I've been out on the
boat 4 of the last 5 days, and then heading to Jamaica for the honeymoon
so I've gotten my share of water time.

Thanks for the good words.
BKH