Ducati Monster Forum

Moto Board => Tech => Topic started by: Brent on May 09, 2013, 04:09:55 PM

Title: 1999 m 900 dying after hot
Post by: Brent on May 09, 2013, 04:09:55 PM
This has only happened  a few times, ill be riding for over an hour and the bike runs fine then all of a sudden when i go to accelerate is stalls out, but it will run on the choke, i pull over let it sit for 20-30 min maybe less fire the bike and it runs fine and then it wont happen for months, cant seem to see anything wrong but i also have not looked all that hard
Thanks for the help
Title: Re: 1999 m 900 dying after hot
Post by: MotoPsycho on May 10, 2013, 01:40:24 AM
Listen for the gas cap to suck air next time. Could possibly be a vapor lock on the gas tank. From what I remember that could be a vent line pinched or something.
Title: Re: 1999 m 900 dying after hot
Post by: Howie on May 10, 2013, 04:45:47 AM
First try GRUBBY's suggestion.  If that doesn't work, check for fuel starvation.  Carry an 8mm. wrench and something to drain fuel into with you.  Open the drain on a float bowl and see how much fuel comes out.  Note quality too.  Water and yuck will fall to the bottom.

float bowl drain

(http://i298.photobucket.com/albums/mm276/hlep2890/bike/IMG_0385-1.jpg) (http://s298.photobucket.com/user/hlep2890/media/bike/IMG_0385-1.jpg.html)

Possible culprits are fuel filter (if over 6K miles, change anyway).
Faulty vacuum operated fuel shut off.
Fuel pump.
Mesh filter at carbs.
Fuel hose from pump to carbs collapsing when hot.
Title: Re: 1999 m 900 dying after hot
Post by: krista on May 10, 2013, 01:09:46 PM
My $ is on the fuel pump. Sounds so familiar...
Title: Re: 1999 m 900 dying after hot
Post by: memper on May 11, 2013, 07:38:37 AM
If it is the pump I have an OEM vac pump I can sell you.
Title: Re: 1999 m 900 dying after hot
Post by: Brent on May 11, 2013, 09:30:57 AM
It cant be a pinched vent line or fuel filter, because ive removed the evap canister, and the fuel filter is new i was thinking of taking the float bowls off and seeing if there was any crap in them from the rubber fuel lines deteriorating from the inside but i will check
the float bowl drain first. If it was the fuel pump wouldn't it not start or act up more often?
Title: Re: 1999 m 900 dying after hot
Post by: Howie on May 11, 2013, 11:53:33 AM
Over time the diaphragms will weaken, ethanol possibly speeding the process.  Add some heat to the recipe and volume is reduced just enough to cause problems.
Title: Re: 1999 m 900 dying after hot
Post by: krista on May 11, 2013, 12:17:54 PM
Yeah, it takes a while before it becomes permanent. The best way to cause a permanent failure is to ride 100 miles away in 100 degree heat of summer. Sure fire way to get Murphy involved to help you with your troubleshooting. My Pongo (97 M900 mutt bike) has it's OEM pump fail in El Centro. I was literally sleeping while riding pillon with z!na back to San Diego. Then back out to El Centro with the van. Then back to San D with the bike and van. That was a long day.

Oh, before buying expensive OEM pumps, we have an aftermarket one for pretty cheap. Started selling it after that's what I used to fix Pongo.

:) Chris
Title: Re: 1999 m 900 dying after hot
Post by: Brent on May 12, 2013, 08:49:50 AM
thanks for all the help ill be ordering a fuel pump shortly