Charging light alarm..YSM8

[Warren Kaplan]

The yard just replaced my waterpump and everything is working fine along those lines. But since that time when I go to start the engine, the engine starts right up but the charging light alarm on the instrument panel doesn't shut right off.

To back up a minute, on the YSM8, when the key is put into the ignition and the start button is pressed all the alarm lights normally come on and the buzzer alarm normally sounds while the starter motor is cranking. But that stops within a few seconds after the engine actually starts and the start button, cranking the starter motor, is released.

Now here's the scenario. The alarm light and buzzer do not go off in the normal amount of time so I shut the engine off. I've done that maybe 2-4 times at the begining of each sail and then, finally, everything goes normal. The engine starts up and the alarm light and buzzer go off on let's say the third try.

This seems to happen after a long lay off. If I run the engine and shut it off, then sail for 3-4 hours, and then start the engine again, everything works normally.

The batteries are charged. After the engine is run and I check the batteries immediately after shutting the engine down, I get the usual 14 or so volts on the meter, which always happens right after the engine has been run. So I know that the alternator is at least working when the alarm is off.

The belt tension seems to be okay but perhaps its a little loose. The adjustment nut to tighten the tension is at its maximum so I can't do anything with that. I don't see any oil on the belt that may make it slip at the very first startup.

I still think it has to do with belt tension in some way. After all to change the water pump all that had to come out and be replaced.

I haven't put a meter to the alternator but I have to believe its working because the batteries in fact do charge quite well once the alarms go off. I don't think it the alarm light and buzzer themselves but I suppose it could be.

Any ideas or suggestions would be welcome!!

Warren

[mgphl52]

Could it be just a loose connection to the alarm light?

[tartansailor]

Lets say that minor slippage is suspect.
There is a belt dressing spray found in auto parts stores
that contains a sticky tackifier intended for such a purpose.
Rosin for bow strings might work if you can not locate
a dressing locally.

Dick

[Warren Kaplan]

Thanks guys,

I was thinking about trying the spray first but I forgot the name of it. I'll run over to the auto store tonight and get some. If that doesn't work I start looking for a loose wire connection.

Thanks again

[Mike Raehl]

Warren,
Are you sure you have the correct belt on the alternator and/or is it possible the new water pump installation resulted in a new, longer alternator belt?

I have plenty of adjustment room on my YSM8 alternator to achieve the specified 5 to 10 mm deflection tension (measured with a 5 mm open end wrench) using a new belt.

You didn't mention which alarm light is slow to go out. If all three lights (charge, water temp and oil pressure) are acting the same, then I would highly suspect the alternator belt tension. The alarm lights and the alarm buzzer are all wired into the same alarm circuit energized by the alternator.

Per the YSM8 service manual: Problem "Lamp not extinguished while engine running." Solution 2: "The no-load voltage developed by the alternator is low." Sounds like blet slippage.

Have a great summer.... Roberta Jane III is sailing happily from Belmont Harbor, Chicago. Also the location next week of the 2008 Etchells World Championship races. Lots of activity in the harbor with skippers and boats from as far as New Zealand and Australia. I plan to cruise out to the course as a spectator boat.

[Ken Textor]

Warren,

If that?s the original YSM-8 alternator, at 28 years old, it?s a pretty good candidate for acting funky at times. Internal connections, wiring corrosion, carboned brushes, etc., make the alternator pretty sensitive after living in a marine environment for such a long time. The fact that the symptoms come and go, and seems connected to how well the engine is warmed up, leads me to think first of the alternator. The good news is most alternators do not die a sudden death. So you don?t need to yank it out right now for expert examination And, if it does die, most alternators can be brought back from the dead by a good starter/alternator repair shop, which are usually numerous in any heavily populated area because autos and such go through this stuff all the time.

Also, whenever someone mucks around in your engine room, he (or she) can inadvertently bump a wire, compromising a ground or creating a gap which may result in intermittent electrical problems. I?d check any wire that the mechanic may have bumped for a bad connection.

The belt solution seems a low probability to me. Enough slippage to produce an alarm is usually audible, as in the belt squeals on the pulley. Even without squealing, you?d see glazing on the belt where it contacts the pulley. And finally, over-tightening an alternator belt can be harmful to the long-term life of the alternator. Too much tension can make the alternator?s shaft bearing wear out fairly quickly.

Hope this helps,

Ken Textor, s/v Marie Rose (CD 27 hull #139)
Arrowsic, ME
________
Bmw Xdrive History

[Warren Kaplan]

As today seems to be a day with a forecast of very low winds here in Oyster Bay, I think I'll get out the manuals and test lamps/multimeters and make an effort to trace down and solve the problem. I'll try and do some things to the belt first to see if that solves the problem. If it doesn't I'll look for loose wires etc. Actually, I'll look for loose wires anyway but you get the idea. If I can't find the problem, I'll have the yard guys check it out when I'm back at work during the week since they were the ones who put in the waterpump. Maybe they caused the problem and they'll fix it for nuttin'. (Dream on, Warren. Dream on!! )

[Warren Kaplan]

Well...I got to the boat and sprayed the alternator belt with "belt dressing". Supposed to prevent belt slippage among other things.

I turned on the ignition. All the alarm lights lit and the alarm buzzer sounded, as its supposed to do when the starter motor is cranking. Within a second or two after the engine started the alarm buzzer and charge light went out as it normally is supposed to do.

So, either this was just a lucky break or the application of belt dressing to the new alternator belt stopped slippage and all is back to normal.

Only time will tell. If the alarms continue now to act normally, I would have to say that the belt dressing worked. If the charge alarm continues to act abnormally, then the belt dressing did not do the trick.

Stay tuned!!