Ducati Monster Forum

Moto Board => Tech => Topic started by: TrevOwnz on June 04, 2010, 01:14:55 PM

Title: '99 Duc M750 Gas Leak
Post by: TrevOwnz on June 04, 2010, 01:14:55 PM
When I got to work I noticed I was covered in gas, I looked and saw gas was coming from a small valve which I guessed to be a bleeder valve? I looked to find the problem and saw rocks/dirt/crap in the gas line near the filter. My tank isn't made of metal I thought so it can't be rust. Is this crap making the gas back track out of a bleeder valve or is there another problem you guys might think I'm having.
Title: Re: '99 Duc M750 Gas Leak
Post by: Popeye the Sailor on June 04, 2010, 02:23:30 PM
Is this an aftermarket plastic tank? Why do you say it's not metal?
Title: Re: '99 Duc M750 Gas Leak
Post by: ducpainter on June 04, 2010, 05:28:04 PM
A 99 750 certainly had a steel tank when it left the factory.
Title: Re: '99 Duc M750 Gas Leak
Post by: TrevOwnz on June 04, 2010, 07:18:43 PM
well I think it's not metal because a couple people have knocked on it and it doesn't sound like metal and they say it's probably something else. It could be but doesn't sound like metal. Do you think it's rust in my line?
Title: Re: '99 Duc M750 Gas Leak
Post by: Ducatl on June 04, 2010, 09:18:24 PM
Can you be more descriptive on the valve part? I take it you aren't the original owner? You say in the gas line so I take it that the line is clear?  Maybe somebody installed a quick disconnect that's leaking? There were rocks...in the gas line?
Title: Re: '99 Duc M750 Gas Leak
Post by: ID_DUC_MON on June 05, 2010, 05:10:26 AM
Should be steel. Do magnets stick to it? Anyway, was your tank full, first hot day in a while, was the stand sitting in low spot causing the bike to lean over more than normal?
Title: Re: '99 Duc M750 Gas Leak
Post by: ducpainter on June 05, 2010, 05:17:59 AM
After re-reading the OP...

It sounds like the vacuum petcock is leaking
Title: Re: '99 Duc M750 Gas Leak
Post by: ID_DUC_MON on June 05, 2010, 06:31:00 AM
Quote from: ducpainter on June 05, 2010, 05:17:59 AM
After re-reading the OP...

It sounds like the vacuum petcock is leaking

I was thinking the same thing since mine just did that. Installing manual one this weekend.
Title: Re: '99 Duc M750 Gas Leak
Post by: TrevOwnz on June 05, 2010, 10:32:47 AM
Yeah I'm not the original owner and I know nothing about bike mechanics, all I know how to work on is Beetles lol.

Where it's leaking from is a little valve about the size of a small straw and half a inch long on the front of the engine. It was dripping gas straight out of it when I was looking at it after work but when I was riding there was a lot coming out all over my left shin. When I was talking about the fuel line I mean the line that is connected to the fuel filter (this http://www.racepages.com/images/products/thumbs/fram/AHG4164.jpg (http://www.racepages.com/images/products/thumbs/fram/AHG4164.jpg)). It had rocks/sand/ in a inch of it making me think it is clogged. Should I try getting the crap out and seeing if it still leaks?
Title: Re: '99 Duc M750 Gas Leak
Post by: ducpainter on June 05, 2010, 10:44:02 AM
Quote from: TrevOwnz on June 05, 2010, 10:32:47 AM
Yeah I'm not the original owner and I know nothing about bike mechanics, all I know how to work on is Beetles lol.

Where it's leaking from is a little valve about the size of a small straw and half a inch long on the front of the engine. It was dripping gas straight out of it when I was looking at it after work but when I was riding there was a lot coming out all over my left shin. When I was talking about the fuel line I mean the line that is connected to the fuel filter (this http://www.racepages.com/images/products/thumbs/fram/AHG4164.jpg (http://www.racepages.com/images/products/thumbs/fram/AHG4164.jpg)). It had rocks/sand/ in a inch of it making me think it is clogged. Should I try getting the crap out and seeing if it still leaks?
I'm confused...

Can you take a picture?

A dirty filter won't make it leak.
Title: Re: '99 Duc M750 Gas Leak
Post by: TrevOwnz on June 05, 2010, 11:05:54 AM
well it's clogged so my brother thought maybe it's coming out of a bleeder valve or something.

I can't actually take a picture today it's at a friends house and I have work in 30 mins so I will do it tomorrow. Thanks for the help though.
Title: Re: '99 Duc M750 Gas Leak
Post by: Ducatl on June 05, 2010, 02:19:59 PM
The front of the engine? Like from a line running out of the carburetors?  

The OEM fuel filters are not clear like that and you can't really see into them.  They're not meant to be cleaned, it should just be replaced. Napa sells a filter that can be substituted for OEM, IIRC it's NAPA 3032.  You can also just go to Autozone etc. and they should be able to get you a decent replacement.
Title: Re: '99 Duc M750 Gas Leak
Post by: ducpainter on June 05, 2010, 02:26:33 PM
Quote from: Ducatl on June 05, 2010, 02:19:59 PM
The front of the engine? Like from a line running out of the carburetors?  

The OEM fuel filters are not clear like that and you can't really see into them.  They're not meant to be cleaned, it should just be replaced. Napa sells a filter that can be substituted for OEM, IIRC it's NAPA 3032.  You can also just go to Autozone etc. and they should be able to get you a decent replacement.
The filter on the OP's bike is translucent plastic and mounted on the exterior of the tank.

The 3032 is for injected bikes typically, but would probably work on a carbie.
Title: Re: '99 Duc M750 Gas Leak
Post by: Ducatl on June 05, 2010, 02:32:44 PM
Quote from: ducpainter on June 05, 2010, 02:26:33 PM
The filter on the OP's bike is translucent plastic and mounted on the exterior of the tank.


Right, but all the carbie filters I've seen are too opaque to actually see into.  The 3032 also works but doesn't really orient the hoses as per factory.

Kinda sounds like carb drain tubes? maybe the PO cut them really short as the OP is describing.
Title: Re: '99 Duc M750 Gas Leak
Post by: ducpainter on June 05, 2010, 02:49:50 PM
Quote from: Ducatl on June 05, 2010, 02:32:44 PM
Right, but all the carbie filters I've seen are too opaque to actually see into.  The 3032 also works but doesn't really orient the hoses as per factory.

Kinda sounds like carb drain tubes? maybe the PO cut them really short as the OP is describing.
You can see when they get dirty IMO. He may have something else besides a factory type filter.

You can get an exact replacement for the carbie filter at autozone...It's for a Fiat or some other common Euro econo box. They usually have them displayed on the wall.

Maybe...

and that might indicate dirt in the float needles.
Title: Re: '99 Duc M750 Gas Leak
Post by: greenmonster on June 06, 2010, 02:08:32 PM
QuoteWhere it's leaking from is a little valve about the size of a small straw and half a inch long on the front of the engine.

Sounds like the float bowl drain lines to me.

Hanging float causing the problem?
Title: Re: '99 Duc M750 Gas Leak
Post by: TrevOwnz on June 06, 2010, 02:37:15 PM
The friend that is holding the bike ATM said he thinks its the same thing that happen to his. Said the crap in my line prob jammed something in the carb causing it to run out. We called a local service guy and he said he will flush it and take a look for me.