Ducati Monster Forum

A red light turns green, I give it some gas and the lights blink on and off and the bike just dies right there. I notice a buzzing from under the seat when I turn the key and the lights do not come on. I have been riding all morning and all last night without incident.

When I got it home a couple of hours later I popped the seat and took a look.

The highlighted part (regulator? *edit= I guess it's the main relay) is the thing that's buzzing. Removing it removes the buzz but I'm not sure that is conclusive proof that it is the cause of the failure:

(http://img5.imageshack.us/img5/4053/buzzing.jpg)

Also, when checking the fuses (none were blown) I noticed a significant amount of gunk/corrosion in the socket for the 25/Master fuse:

(http://img6.imageshack.us/img6/7951/thiscorrosion.jpg)

Any ideas or suggestions? I would like to just go buy a new *edit=main relay and try it but I'm not sure if that is the definate fix. Also I would love to hear how I can clear out all that crap in the master fuse socket. Q-tip and dental tools?

Thanks!

Oh man, sorry I just saw this thread: http://ducatimonsterforum.org/index.php?topic=23113.0 (http://ducatimonsterforum.org/index.php?topic=23113.0)   [clap]

I will thoroughly investigate it and let you know if I can fix this problem. Sorry!

I would still love some ideas on cleaning out the corroded fuse socket.

Best fix would be a new fuse box, except it seems the fuse box may not be available as a separate part, check with a dealer to be sure.  If that connector is the only one that has suffered and the heat did not weaken the connection and the wires are not overheated a good cleaning might work.  If not, take a trip to a good auto parts store, buy a blade fuse holder for the appropriate amp rating, cut back the burnt wires until you get to the good stuff and find a good place to hang it buy the fuse box.  Ummm, your photo shows a 25 amp fuse, my bike uses a 30 amp.  Something else for you to check out.  As far as the relay goes, you can open it up and inspect and clean the points if needed.

Thanks for the reply! I tried opening the relay box and all the points and connections in there seem good. I made sure to wet sand/clean it a little anyway to be sure. This did not fix the problem - it still buzzes and doesn't start up.

Edit: Oh man, the manual does say 30 amp. Well that's not good...

The other thread suggested that a bad or undercharged battery might not be giving the relay enough power to get it going.

This is my first bike and I'm sort of new to the maintenance and mechanics of it all. The bike's a used '99 M750 and I figure there are worse things I could do than buy a new battery just for peace of mind. Trouble is I couldn't find a guide on getting my tank up (full of gas at the moment =/) and replacing the battery. I'd love to go to a dealer buy a battery and get this fixed tomorrow morning. I should stress I don't have a way to get it to the dealer. Any suggestions?

Thanks again!

Edit: oh, and I will be looking into the fuse holder if I cannot get it cleaned to acceptable degree.

The bad connector for the fuse will cause low voltage to the relay as well as an awful lot of the rest of the bike.  Yes, a low or bad battery can cause this, but you still need to fix the root cause, which is that connection.  Running the 25 amp did not cause this problem, it is just  a weak link since, if it blows, the bike stops running.

As far as the battery goes, if it is old you might want to replace it now rather than later, but if you charge it and bring it to a shop and get it load tested you will know if it is good or bad.

Okay well, I found out that basically none of the fuses in the fuse box were the correct kind (Instead of a 30, 7.5, 15, 7.5, 7.5 there was 25, 7.5, 15, 15, 15).

Pretty frustrating... The good news was that the wire surrounding the fuse box appeared not to be burnt or otherwise compromised. I bought the fuse holder just in case but I was dreading having to install it! $4 credit coming to me at Auto Zone could be worse.

I sorted out all the correct fuses and wet sanded and cleaned all the electrical contacts involved, including a thorough scrape-and-spray of the fuse socket for the main fuse (squeaky clean now). I noticed a tremendous amount of buildup on the battery connector leads which I promptly cleaned. None of this got it working although now all the connections were clean it seemed that the buzzing had gotten louder!

I ended up buying a new battery because I figured there were worse things I could do. When following the instructions in the manual on how to install it I noticed that I am missing a "breather hose" or it's end is lost somewhere in the gubbins under the tank. I connected it all up anyway and it started like a charm! I rode around for a while and everything seems great.

Mostly good news. My concern now is that missing breather hose... I noticed the old battery did not have a connector for one but I would still feel a lot better about things if everything was properly set up.

Is the breather hose supposed to connect to another part on the bike or is just a short length of hose to vent off gas out from under the seat? Where/how can I get a cheap one? and/or where can I find my original one under the tank?

Thanks!

Locate this part

(http://i298.photobucket.com/albums/mm276/hlep2890/bike/PCVConversion1.jpg)

If  there is a small filter on it or a hose that has a filter on the end of it, the previous owner eliminated the breather box (common modification).  If not, you need a hose.

Are you referring to a battery breather hose?

Sealed batteries don't have them.

Okay, that part doesn't seem to have any sort of filter connected and the pipes don't lead to anywhere near the little spigot thing on the side of the battery that according to the manual seems to be wanting the hose.

Here is Fig. 40 from the manual. The breather tube I'm looking for is marked (2).

The accompanying text is: "...make sure the breather tube must be so placed (sic) that it does not kink or twist. A kinked or twisted breather tube may lead to overpressure and damage the battery."

(http://img213.imageshack.us/img213/5760/breatherhose.jpg)

Thanks for staying with me on this one!

Yes, the battery breather hose. The new battery I bought is the OEM battery Yuasa YB16AL-A2. Should I have gotten a sealed battery instead? Oh man, so much to learn!

I run the same battery.

With no special care they last 5-6 years. I think they're great.

Get a breather for it. If you don't you'll stain the frame.

You can use vacuum tubing if you can't get the clear stuff.

Okay awesome, I was worried I had screwed-up getting an unsealed battery! So I get some tubing and just run it down to the bottom under the engine facing to the floor away from the engine and frame?

Is this just standard automotive or surgical tubing? If not where can I get it?

Sorry for so many follow-up questions, I really want to do this right. I appreciate both of your help!

Oh, that hose :P  As long as the hose you get is the right size and acid resistant you will be good.

Pretty much. All you need is a path that only heads down with no kinks. I routed mine behind the engine in front of the rear tire.

I've been using some auto vacuum line for about 5 years because the original was too short to go where I wanted it.

I think I used 1/8" or 3/32". You could probably get a few feet of each for cheap if you can't measure the nipple on the battery.

Thank you so much!

Okay so I bought a new battery and made all the adjustments and the bikes been riding great for about a week. It turned on and rode fine yesterday night and now, less that 24 hours later, the bike will not start. The lights won't even come on and there are no signs of life.

I plugged the battery into a Battery Tender and the red light keeps flashing (indicating a battery is too low, less than 3 volts).

So what else can be the problem? Alternator? Regulator?

Thanks for your continued help in this matter. It has become quite frustrating.

Edit: I should specify that there is actually no buzzing from the relay box now.

Lots of could bees. 

Fully charge the battery, then use this trouble shooting guide:
http://www.electrosport.com/technical-resources/library/diagnosis/fault-finding-guide.php (http://www.electrosport.com/technical-resources/library/diagnosis/fault-finding-guide.php)

Hint - A bad connection where the stator connects to the regulator is a common problem area.