Ducati Monster Forum

Good day all, I've had a couple motorcycles and cars over the years, pretty mechanically inclined but this one has me stumped!

The bike runs fine on brake clean/pouring fuel in the throttle bodies.

I have so far:

replaced the fuel pump, fuel filter (used napa one, have it facing the right direction), in tank fuel line
sent injectors off to get cleaned/flowed - the results they were not that clogged
fresh spark plugs
fresh timing belts
fuses all good.
have bike on charger when turning over, turns over strong.
I soldered together the clutch cut off switch wires so neutral start no longer matters.

The fuel pump primes, the injectors do shoot fuel spray.

The  bike has spark.

I'm thinking at this point a fuel line to the injectors is clogged or something?  It's weird because the injectors are firing pulses of fuel (I removed an injector from cylinder head and turned bike over to see the fuel spray)- but the bike will not run off this, but if you pour fuel into the throttle bodies it will idle happy all day till that fuel runs out.

I'm installing new fuel line from fuel tank (external) to the injectors.

Any ideas?  I have the 'M' line from the fuel tank mounted to the back of the gas tank (tail light side),  I also tried switching lines around that did not fix.

Also I dont see a fuel pressure regulator on the bike, just goes to injectors from gas tank unless I'm missing something.

*could timing be off a tooth causing the injectors to pulse at the wrong time?  It does idle well when fuel is poured into throttle body.  No missing.

Thank you!!

Most likely you've got the lines installed backwards on the tank.
Fuel lines came with a little white plastic ring on them, M (Mandata) is Feed, R (Retornar) is Return.
There was a sticker on the bottom of the tank that shows where to hook them.

FP regulator is on the throttle bodies.

Fuel pressure should be ~45psi
You'll need to Tee into the M line to check.

Thank you for the reply.

The M line is on the M line of the tank diagram that is on the back of the fuel tank.

Today took the gas cap off again and looked at the fuel pump, it primes and is sitting in a good bath of fresh fuel.  I then took the line off post filter to see if the filter was plugged, turned on ignition fuel will spray out of the filter.

I replaced the submersible gas line that goes from filter to hardline of the fuel tank, also new submersible line from fuel pump to fuel filter.

I then replaced the main fuel line to injector with proper fuel injection hose, no resolution, except all the fuel that did spill into the throttle bodies during this bloody messy procedure did get the bike to start and idle for a couple of seconds.

I have tried reversing these lines that you mention from the fuel tank, that does not get the bike started.

I have just ordered an inline fuel pressure gauge to run pressure on the M line to see what it is getting.

It does seem like the spray is weak off the injectors.

I will check the timing on the bike tonight, maybe the injectors are firing at the wrong time if out of time?

Do many people experience gunked up fuel pressure regulators?  

I think the following maybe the culprits:

-Bad wiring harness to injectors not giving full voltage
-Bad Fuel pressure regulator
-Bike is somehow out of time having injectors fire at the wrong time

Where is the FPR?  These throttle bodies pictured are identical to mine, fuel lines and all, I am not seeing a FPR.

(https://i.ebayimg.com/images/g/s34AAOSwTQtaKr45/s-l500.jpg)

https://www.ebay.com/itm/Ducati-Multistrada-620-05-Throttle-Bodies-Body-Fuel-Injectors-7K-Miles-2005-OEM/272974477360?hash=item3f8e8bf830:g:s34AAOSwTQtaKr45:sc:USPSPriority!27601!US!-1:rk:10:pf:0




Open to ideas thank you!

Mine does not have this FPR. pictured on this setup, my bike was imported from Italy, reads in kilometers as well.

The previous owner did buy this bike as it had red plastics/gas tank (plastic tank) and swap the steel tank over to from his wife's 620 to this one.  Do the plastic tank motorcycles have a fuel pressure regulator in the gas tank or something different?  I think we may be onto something!!

(https://i.ebayimg.com/images/g/9y4AAOSwUKxYcBF7/s-l500.jpg)

Is this what I'm missing?

https://www.ebay.com/itm/2004-DUCATI-MONSTER-620-M620-MAIN-FUEL-INJECTORS-THROTTLE-BODIES/291993408745?fits=Make%3ADucati&hash=item43fc29d4e9:g:9y4AAOSwUKxYcBF7:rk:16:pf:0

here is what my current tank looks like on the bottom:

(http://i201.photobucket.com/albums/aa52/afakhori/gastankfairing005.jpg)
(http://i201.photobucket.com/albums/aa52/afakhori/gastankfairing006.jpg)

Where does the FPR vacuum line attach to?

Thanks again!

OK, first things first.

You are going back and editing earlier posts in response to suggestions from later posts.

This radically confuses the troubleshooting process for folks who refer to this thread later.
Also, you're confusing the folks who are trying to help you by changing your original presentation of the problem.
When you revise the history and confuse the folks that are trying to help, they are less likely to continue trying to help.

Now I know why I got a headache.  Any way, you might have a pressure regulator integral with the fuel pump like a 695.  Don't know for sure since the bike is for the home market.  On the external pressure regulators what looks like a nipple for a vacuum hose is just a vent.  Assuming you have no leaks inside the tank your next step is a pressure test.

I ordered the regulator. 

There is no regulator internal to the steel gas tank that is on my bike,  I believe the plastic gas tanks had them mounted to the tank somewhere.  On this steel gas tank, Just a generic fuel pump, fuel filter, fuel level sensor.

With no regulator the pressure never builds and it returns to the gas tank. 

I have an inline fuel pressure gauge on the way.

Thanks for your help guys - didnt mean to confuse.  I would post a recent response, then think of more relevant information and add to that post.

Will keep you posted - regulator/throttle body setup should arrive in 1 week.

Pressure regulator is internal on plastic tanks...external on steel.

You are trying to run a bike without a pressure regulator.