Ducati Monster Forum

Moto Board => Tech => Topic started by: puddles on February 28, 2014, 06:40:56 AM

Title: Bog, falling on its face
Post by: puddles on February 28, 2014, 06:40:56 AM
I have a 2000 900ie. It runs great for the most part. Starts easily and idles fine. However, usually when I'm on the highway, and I pin the throttle, it will bog and fall on its face. Then usually buck, on and off the power. It won't do this if I roll-on the throttle. The bike only has 9000 miles on it. I did check the valves last night, and although it was my first time checking them on a Ducati, I am an accomplished air-cooled VW mechanic, so this wasn't completely foreign. Although I don't completely understand the closing gap concept. Either way the valves seemed good. Maybe a hair snug, but nothing bad. This bike also has aftermarket pipes on it. It had the stock air filter, but I just tried putting a K&N in it thinking that maybe air flow was an issue with the exhaust. No luck. Maybe even a little worse. Plugs look ok, but maybe a bit lean. I have changed the plugs. Closest dealer is 2hr away. Can you guys think of anything else I should check before taking it to a shop? Thanks.
Title: Re: Bog, falling on its face
Post by: ducpainter on February 28, 2014, 12:41:06 PM
How does it run during extended WOT?

Has the fuel filter ever been changed?
Title: Re: Bog, falling on its face
Post by: puddles on February 28, 2014, 02:47:01 PM
I've never kept it at wot with the bucking. I've never changed the fuel filter. How does one go about changing it? Do I have to remove the pump assembly, or can I get to it from the top by taking the filler neck assembly off?
Title: Re: Bog, falling on its face
Post by: ducpainter on February 28, 2014, 02:53:09 PM
The filter is accessed through the top. There are a ton of threads about how to get in there.

What you see on the bottom is just the sender. The pump is inside and also accessed through the top, but unless you see a ton of rust there's no reason to remove the pump.

The NAPA 3032 fuel filter is an inexpensive replacement.

The early injected bikes were set up pretty lean from the factory. Ultimap, now out of business, used to have a map that could be flashed onto the ecu, but I'm not sure if anyone still does it.
Title: Re: Bog, falling on its face
Post by: puddles on February 28, 2014, 03:29:48 PM
Thanks for the fuel filter info. I will change it just to be sure. There is no rust in the tank. I was thinking that the mapping was a problem. Is this something a Ducati dealer could do?
Title: Re: Bog, falling on its face
Post by: Speeddog on February 28, 2014, 03:41:11 PM
There was a Ducati Performance ECU avaliable for the early FI as well.

You may also have fuel lines that are deteriorating.
I've seen a couple cases where the lines are leaking to an extent that the fuel pressure is low, but the bike will run OK around town but poorly on the freeway or high load.

Fuel line deterioration is common on bikes that have been sitting for over a year with fuel in the tank.

Use only either OEM line specific to FI tanks, or immersion-rated line ( spec is 30R10 ).
30R9 FI fuel line will fail in short order when immersed.
Title: Re: Bog, falling on its face
Post by: ducpainter on February 28, 2014, 03:53:50 PM
Quote from: puddles on February 28, 2014, 03:29:48 PM
Thanks for the fuel filter info. I will change it just to be sure. There is no rust in the tank. I was thinking that the mapping was a problem. Is this something a Ducati dealer could do?
Only if they still have the Ultimap software.

You might contact eric at clubhousemotorsports dot com

I think he has the ability to reflash that vintage ecu. I know he can't do the chip burning for the next series of Ducati ecu's.
Title: Re: Bog, falling on its face
Post by: puddles on February 28, 2014, 05:48:13 PM
Quote from: Speeddog on February 28, 2014, 03:41:11 PM
There was a Ducati Performance ECU avaliable for the early FI as well.

You may also have fuel lines that are deteriorating.
I've seen a couple cases where the lines are leaking to an extent that the fuel pressure is low, but the bike will run OK around town but poorly on the freeway or high load.

Fuel line deterioration is common on bikes that have been sitting for over a year with fuel in the tank.

Use only either OEM line specific to FI tanks, or immersion-rated line ( spec is 30R10 ).
30R9 FI fuel line will fail in short order when immersed.
So you are referring to the fuel lines in the tank correct? So either a performance ecu or flash the original?
Title: Re: Bog, falling on its face
Post by: Speeddog on February 28, 2014, 05:58:55 PM
Yes, the lines inside the tank.

External lines can be 30R9 spec.

I've not seen a re-flashed ECU, and I've no idea how they compare to the Ducati Performance unit.
Title: Re: Bog, falling on its face
Post by: puddles on February 28, 2014, 06:32:34 PM
Funny, I can't find a thread on removing the fuel filter. I have the filler cap removed and can see the filter and pump, but can't see how to remove the pump to get the filter out.
Title: Re: Bog, falling on its face
Post by: ducpainter on February 28, 2014, 07:04:14 PM
Quote from: puddles on February 28, 2014, 06:32:34 PM
Funny, I can't find a thread on removing the fuel filter. I have the filler cap removed and can see the filter and pump, but can't see how to remove the pump to get the filter out.
The flange the cap screws to must be removed.

There are 8 small allen screws around the circumference of the flange. Loosen them about 1/8".

Insert a hammer handle in the fuel opening and give it a rap with your hand. Keep the other hand under the head of the hammer. They can be stubborn if they haven't been out in a while.

Grease the green o-ring on re-assembly. The black gasket can be a PITA.
Title: Re: Bog, falling on its face
Post by: puddles on February 28, 2014, 07:12:52 PM
I have the filler cap off, I'm confused on how to remove the pump.
Title: Re: Bog, falling on its face
Post by: brad black on February 28, 2014, 11:40:31 PM
guzzidiag allows you to flash the 15m and 15rc as well as the 5series.
Title: Re: Bog, falling on its face
Post by: ducpainter on March 01, 2014, 03:45:36 AM
Quote from: puddles on February 28, 2014, 07:12:52 PM
I have the filler cap off, I'm confused on how to remove the pump.
You don't have to remove the pump.

The pump is at the very bottom of the tank near the seat. A single fuel line comes out of it. The filter is in that line. It is a metal can about 1 1/2 in diameter and 3 inches long. You should be able to see the filter if you have the flange removed.
Title: Re: Bog, falling on its face
Post by: puddles on March 01, 2014, 04:49:03 AM
I see the filter and pump, but it seems impossible to get to the clamps on the inlet side of the filter to remove it.
Title: Re: Bog, falling on its face
Post by: Ddan on March 01, 2014, 05:09:38 AM
Undo the clamps at the top end of the filter and pull that short piece of hose off.  The pump is in a rubber sleeve that's held into a spring clamp. Work the pump out of the spring clamp and pull the whole thing out to the filler hole.  Watch the wires.

(https://c2.staticflickr.com/4/3760/12854013733_a915334a80_o.jpg) (http://www.flickr.com/photos/23081877@N02/12854013733/)
Title: Re: Bog, falling on its face
Post by: puddles on March 01, 2014, 05:19:10 AM
Cool, that makes sense. I take it the inlet screen will fall off when pulling the pump through the rubber spring mount? Installation is just reverse, work the pump back into the spring clamp? Install inlet screen after installing pump? Thanks.
Title: Re: Bog, falling on its face
Post by: Ddan on March 01, 2014, 05:31:34 AM
The inlet screen stays on the assembly.  It can be a bit of a pregnant dog getting the pump back in the clamp, there's not much room.
Title: Re: Bog, falling on its face
Post by: ducpainter on March 01, 2014, 06:06:32 AM
The pump needs to move up to the top surface of the tank then towards the filler.

I have more  trouble getting them out than back in.
Title: Re: Bog, falling on its face
Post by: Ddan on March 01, 2014, 06:13:03 AM
Quote from: puddles on March 01, 2014, 05:19:10 AM
Cool, that makes sense. I take it the inlet screen will fall off when pulling the pump through the rubber spring mount? Installation is just reverse, work the pump back into the spring clamp? Install inlet screen after installing pump? Thanks.
I just re-read this.  The pump doesn't pull through the rubber, it all gets pried up out of the clamp.  DP's right, it's harder to get out than back in
Title: Re: Bog, falling on its face
Post by: puddles on March 01, 2014, 06:36:49 AM
Ok, so I need to pry the clamps apart to remove. How do you pinch them back together when reassembling? Needle nose pliers?
Title: Re: Bog, falling on its face
Post by: ducpainter on March 01, 2014, 07:20:12 AM
Quote from: puddles on March 01, 2014, 06:36:49 AM
Ok, so I need to pry the clamps apart to remove. How do you pinch them back together when reassembling? Needle nose pliers?
No...you don't bend the clip.

The pump will slide up, it will take some force, and barely clear the clip. There is very little room in there. Sometimes a long screwdriver between the pump sleeve and the clip is necessary. To reinstall a thin film of oil on the rubber sleeve will make it much easier.
Title: Re: Bog, falling on its face
Post by: puddles on March 01, 2014, 01:52:18 PM
Thanks guys for your help. Super easy to change filter. I used a long pry bar to pop the pump out of the spring clips, then just reached in an pushed it back in by hand. That 30R10 hose is *&$%^&@ expensive! 35 bucks a foot from NAPA. The hose in the tank looked fine, it wasn't deteriorating, but the ends where the clamps were was a bit smooshed, so I changed it. Now to wait for better weather. Looking like mid-next week. I'll keep you posted.
Title: Re: Bog, falling on its face
Post by: puddles on March 03, 2014, 03:46:32 PM
That wasn't the problem. It might be a bit smoother though. I'm thinking about pulling the injectors out and checking the spray pattern, as well as replacing all the external fuel lines. Thoughts?
Title: Re: Bog, falling on its face
Post by: ducpainter on March 03, 2014, 04:31:41 PM
Is this a problem that came on suddenly, or has it been like that since you owned it?
Title: Re: Bog, falling on its face
Post by: puddles on March 03, 2014, 05:08:24 PM
Since I've had it, which isn't that long.
Title: Re: Bog, falling on its face
Post by: brad black on March 03, 2014, 05:15:50 PM
physically measure the fuel pressure.

get it on a diagnostic tool and make sure all the sensor inputs are ok.

if the idle trimmer setting is way off it could be an issue, but it should be a pig all round.
Title: Re: Bog, falling on its face
Post by: puddles on March 03, 2014, 06:18:17 PM
I was hoping to eliminate as much as possible before going to the dealer.
Title: Re: Bog, falling on its face
Post by: brad black on March 04, 2014, 12:55:37 AM
you might just be wasting your time doing pointless crap.
Title: Re: Bog, falling on its face
Post by: puddles on March 04, 2014, 06:44:16 AM
What should the fuel pressure be?
Title: Re: Bog, falling on its face
Post by: Speeddog on March 04, 2014, 09:06:47 AM
Quote from: puddles on March 04, 2014, 06:44:16 AM
What should the fuel pressure be?

AFAIK, nearly all FI Ducs should be 45psi (3 bar).

I think it's a few of the SBK R models that are higher.
Title: Re: Bog, falling on its face
Post by: puddles on March 04, 2014, 04:47:14 PM
So I jimmied up a timing light on the bike and took it out. Spark is present during the bucking. I understand this isn't a guarantee of STRONG spark, but I think this points to fuel. It definitely happens under heavy load (lower rpm's with a lot of throttle). The point of a monster right? Now, should I ride it with a fuel gauge jimmied up on the bars, or should I just check the pressure with it running (not riding)?
Title: Re: Bog, falling on its face
Post by: puddles on March 05, 2014, 04:34:03 PM
I jimmied up the fuel pressure gauge today, and the fuel pressure is constant around 46-47lbs. I guess the brain is cutting out the signal to the injectors. Off to the dealer and a scan tool. Thanks for all the help.
Title: Re: Bog, falling on its face
Post by: Blissful on March 25, 2014, 03:06:19 PM
Any updates??? I have the exact same issue on my 2000 M900Sie, and I've tried all the same things you have. I'm taking the bike to the dealer tomorrow, so if you found the problem I'd love to know! Thanks