97 Monster 750 quit mid ride with out any warning (that i noticed)

[careeramateur]

Hey people,

I'm looking for some advice to troubleshoot what might be keeping my bike off the road.

Riding home a month or so ago, she cut out as i came to a stop sign. Fired back up as a crossed the street but cut right back out. Pushed her home, trying to fire it up here and there. she barely considered it

Battery is an 8 month old tru gel. seems to be fine.

With starting fluid blown into the air intake it will choke to life, briefly, barely. right back out.

replaced the fuel filter and and checked the line. in the process drained the tank on the advice of a guy at Munroe Motors. His theory was that rain water had contaminated the fuel tank due to a plugged drain or something. It had been raining then. Indeed the fuel looked less than clear, slightly murky, and it seemed to separate as I observed it in the clear drain tube. It was a little bubbly too. So I thought I'd found the problem. No luck. Fresh fuel and she still won't turn over.

If it had been choking on bad fuel for too long, is other damage likely? do I need to flush the system some how?

I hear the fuel pumps nearly never go bad, but how do I check it without dropping $160 to replace it?

And what else might I check?

Feel free to respond in very simple language. I'm obviously no mechanic and relatively new to ducatis.

Thanks in advance.

[Drunken Monkey]

In the interests of full disclosure, I used to own this bike. Then again, so did Duck Stew, so you can blame him too 

If it chokes to life with starter fluid, I'm thinking you still have spark.

You can test that by pulling a plug and grounding it against the motor with the wire attached and seeing if it makes a spark when you crank the bike.

My theory is fuel delivery. When I had the bike it had a fuel line kinking problem, at least what I thought was a fuel line kinking problem. I 'fixed' it by making sure the lines were routed right. Or "once I checked and fixed the routing of the lines, it went away"

Might be that the line just got so old it collapsed?

Other theories anyone?

[monstermick58]

Two things that will stop a motor, no fuel or no spark. You say it will run briefly when you use starting fluid, well to me thats saying that you have spark, so we need to look at the fuel system.

   Hopefully you have got all the crap out of your tank, check by draining some into a clean container and if the fuel is murky in any way its no good also while you are looking at it look for water in the fuel, it will look like a little bubble sitting at the bottom of the fuel, by the way what grade of fuel are you using?

One more check is to pull both plugs out and have a look to see if they look wet or dry, if they look wet then fuel is getting into the cylinder and it may be a case of bad fuel, dont forget to drain the carby's (I'm assuming it has carbs?) and again catch the fuel into a clean container and look at it for contamination.

Hope this helps. 







                                           Mmick

[tbyte]

Did you empty the float bowls when you emptied the tank?

http://www.ducatimonsterforum.org/index.php?topic=52777.15

[Howie]

Drain the fuel from the float bowls into a clear container and inspect 



Make sure the vacuum fuel shut off works


vacuum applied  open
no vacuum  closed

Make sure the vacuum line to the fuel pump is not kinked,collapsed or restricted

Repeat with the hose from the pump to the carbs, sometimes that hose gets soft and collapses when hot

Either bypass the fuel pump and fill the tank and go for a ride or disconnect hose to the carbs and check for output while cranking, (careful, we are talking about sparks and gasoline)   

[10/10ths]

Blow air through the vent hole under the fuel filler lid.  If this vent gets clogged, the bike will exhibit the EXACT symptoms you are describing.

My 97 M750 did the exact same thing.  I blew out the tank vent hole under the fuel filler lid and it completely solved this problem.

Good Luck.

[Howie]

Blow air through the vent hole under the fuel filler lid.  If this vent gets clogged, the bike will exhibit the EXACT symptoms you are describing.

My 97 M750 did the exact same thing.  I blew out the tank vent hole under the fuel filler lid and it completely solved this problem.

Good Luck.

That too, and a kinked vent line.  Still got the charcoal canister on?

[greenohawk69]

Had something similar to what you're experiencing and...it was my crank case breather ('97 M900).  I have the TPO part with the K&N filter.  The part the screwed into the crank case breather area was very loose - two turns and it came out.  Screwed it back in and it started right up. 

I did look at the other areas that you did also just to ensure there was nothing else I might be missing.  Good luck.

[careeramateur]

Thanks everyone for your tips.

Bit by bit I probably drained about 6 ounces of water out through the float bowl!! I wanted to post a picture of the seperated fuel/water mixture but I can't find the cord to hook up my phone to the computer. It was a lot more than I expected I might find.

Also blew out the vent hole under the fuel cap. Couldn't tell if it was clogged, but now I know it's not.

She will not get left out in the rain without a jacket anymore.

Thanks again! Off to ride in the San Francisco mist!
Happy riding

[Drunken Monkey]

I chatted with careeramateur briefly on the phone. Any clues as to what could be causing that much water in the tank?

The only other advice I have is get some alcohol-based additive to help mix any remaining water into the gas, and keep the tank topped off when you know it's going to rain.