BrianG Posted January 24, 2005 Share Posted January 24, 2005 Is the fuel solenoid valve a common source of fuel leakage? Link to comment Share on other sites More sharing options...
al_roethlisberger Posted January 24, 2005 Share Posted January 24, 2005 Is the fuel solenoid valve a common source of fuel leakage? 41800[/snapback] If you are referring to the electric petcock on the 01-ish and earlier bikes, then.... yes, they are problematic in a number of ways. I don't remember "leaking" being one of them per se, but I can imagine that would be possible given other issues with the things I recommend changing out the electric ones to a manual one as one of the first things to do, as they are so unreliable... and the manual version is about $30 from MPH(if I recall). al Link to comment Share on other sites More sharing options...
BrianG Posted January 24, 2005 Author Share Posted January 24, 2005 I recommend changing out the electric ones to a manual one as one of the first things to do, as they are so unreliable... and the manual version is about $30 from MPH(if I recall). al 41801[/snapback] Thanks!! Is there a manual unit that has 2 positions (normal/reserve)? Alternately, are there separate ones, one for normal and one for reserve? Link to comment Share on other sites More sharing options...
BrianG Posted January 26, 2005 Author Share Posted January 26, 2005 Is there a manual petcock that has 2 positions (normal/reserve)? Alternately, are there separate ones, one for normal and one for reserve? Link to comment Share on other sites More sharing options...
Guest Jeff in Ohio Posted January 26, 2005 Share Posted January 26, 2005 Is there a manual petcock that has 2 positions (normal/reserve)? Alternately, are there separate ones, one for normal and one for reserve? 41947[/snapback] A fuel valve with normal/reserve on it for a fuel injected bike would be a VERY BAD idea. When it finished normal, the fuel pump would suck basically air faster than you could switch over to reserve - causing bad things to happen in the fuel circuit...... Link to comment Share on other sites More sharing options...
BrianG Posted January 26, 2005 Author Share Posted January 26, 2005 A fuel valve with normal/reserve on it for a fuel injected bike would be a VERY BAD idea. When it finished normal, the fuel pump would suck basically air faster than you could switch over to reserve - causing bad things to happen in the fuel circuit...... 41948[/snapback] Jeff, I understand that some FI fuel pumps use fuel for lubrication, but I do not understand what other issues arise from fuel starvation. Also, totally running out of fuel couldn't be any less harmful for the system, and I think depending on an idiot light for that is asking for it. Link to comment Share on other sites More sharing options...
Guest IanJ Posted January 26, 2005 Share Posted January 26, 2005 Jeff, I understand that some FI fuel pumps use fuel for lubrication, but I do not understand what other issues arise from fuel starvation. Also, totally running out of fuel couldn't be any less harmful for the system, and I think depending on an idiot light for that is asking for it. 41950[/snapback] The big issue is purging air from the fuel system, as I understand it. It's not super hard to do, but it ain't gonna happen while you're rolling on the street, switching to reserve. I believe common practice is to install some kind of level-sensing switch in the tank to shut off the engine before air can enter the fuel system (the same switch that lights the reserve light? dunno). When the pump starts sucking air, it runs with no load, which certainly can cause damage to some motors. I would guess a fuel pump is one of those motors. Link to comment Share on other sites More sharing options...
BrianG Posted January 27, 2005 Author Share Posted January 27, 2005 The big issue is purging air from the fuel system, as I understand it. It's not super hard to do, but it ain't gonna happen while you're rolling on the street, switching to reserve. I believe common practice is to install some kind of level-sensing switch in the tank to shut off the engine before air can enter the fuel system (the same switch that lights the reserve light? dunno). When the pump starts sucking air, it runs with no load, which certainly can cause damage to some motors. I would guess a fuel pump is one of those motors. 41951[/snapback] This is interesting theory, but I wonder if anyone here KNOWS the issues at hand. I have first hand experience with this issue in the automotive context, since someone I live with (who shall remain nameless in order to protect the guilty) has a bad habit of running out of gas in her car. It is a FI car with in-tank fuel pump. I have always simply refuelled the thing and started it, with perhaps a few seconds more turnover than usual. It starts right up and runs as if nothing untoward has happened. This is probably something that has happened15-20 times in 2 years. Still no apparent consequences. Let's look at the Guzzi system. Gravity feed to the fuel pump....might naturally purge the air to the pump. Pressurized fuel through the plumbing to the regulator...air shouldn't interfere with that. Pressurized fuel at the injector intake should flow through the solenoid valve unimpeded. The pintle isn't particularly highly spring-loaded, so fuel should pass that too. Aside from potential pump damage (real or imagined) what is REALLY at stake? Anybody have real experience with the Guzzi in this regard? Todd..... do you spend any time replacing failed EFI parts becasue of fuel exhaustion? Link to comment Share on other sites More sharing options...
BrianG Posted January 28, 2005 Author Share Posted January 28, 2005 Does anyone know what the fuel-tank thread size is? diameter and pitch? Link to comment Share on other sites More sharing options...
al_roethlisberger Posted January 29, 2005 Share Posted January 29, 2005 Does anyone know what the fuel-tank thread size is? diameter and pitch? 42102[/snapback] ....don't even try <_> Honestly, it's some odd metric sized and pitch, reverse thread, weirdo that I spent weeks going to various fitting shops trying to find a match to. It's easier, and totally effective, to just spend $40 on the MG manual petcock al Link to comment Share on other sites More sharing options...
todd haven Posted January 29, 2005 Share Posted January 29, 2005 We've replaced a few pumps, mostly in Cali's as opposed to V11's. None on in-the-tank system. Unable to tie to low fuel condition. More likely when bike sits 2-3 months. The petcocks fail when the wires break off-- the manual ones are a good upgrade. The "vapor lock" problem we have only heard of once in Houston-- and were unable to repeat when the bike was in the shop. Bike belonged to a friend-- offered to fix him up w/ fuel pressure guage and instructions for trouble-shotting, but he wimped out. No recurrence in 1 year +. Maybe if it would just get hot here once in a while. Not a big believer in the "boiled-fuel" theory, but been wrong before. Maybe more altitude-related? Still looking for answers. Link to comment Share on other sites More sharing options...
RichMaund Posted January 29, 2005 Share Posted January 29, 2005 I had a '97 Cali 1100. I never ran it out of fuel. But I did have to change out almost all the rubber fuel lines on it because Guzzi screwed up and used some Gates fuel line that wasn't rated for FI systems and multi fuel use. In a year the thing was weeping fuel from fittings and the crimp on connections were loose from the line deteriorating on the inside. I installed better fuel line from a NAPA store rated for FI/multi fuel use. Long story short... The fuel filter on the Cali is mounted in such a way as to trap air inside it if you just install it and then run the bike. It sits angled. It trapped some air, which then later, bit bit, got entrained into the fuel line for the injectors and gave me fits out on the road. It didn't seem to want to stop doing this on it's own. There seemed to be an inexhaustable supply of air in that filter! So I had to take it apart and fill the damn thing on the vertical with a syringe of fuel and tap it to get the air out. I even pulled the lines off at the injectors and cycles the key switch to pump fuel through there for a solid line of fuel. That finally solved it. When I changed out the filter on my V11S, I filled it solid as I installed to prevent problems. It worked fine. No hiccups. Just another reason for me to enjoy my Ural with its carbs. It cut the crap outta my hands changing the hoses on that thing. Very tight spaces to work in. I remember I started quite a flap on the MGCL when I brought this up as there were many guys out there with leaky Cali's. But none had yet found the reason (Improperly rated fuel line used) as I had. My friend's Cali was a year older than mine and was leaving puddles of gas under it when parked! He had our old Dealer, Ken's Cycles in Richmond Va., change his out. Ken's was one of the good old Dealers who got tired of Guzzi screwing them and dropped the bikes after many years. And that was a shame. The Dealer who picked them up just 20 miles away was a jerk who ruined many people to Guzzi's with lousy and incompetent service. Now Winchester is our only Dealer in the state. 240 miles away from me! I won't hesitate to own another Guzzi. But I'd rather build my own to bypass all the headaches the retards that Guzzi hires as bike assemblers cause! OK.... Rant mode off. I'll try to calm down now. <_>I do love seeing all the photos here that Paul posts on his performance and custom built sport Guzzi's. That is really inspiring! And I bet they work better than factory bikes when he's done too. That is quality work! Link to comment Share on other sites More sharing options...
Admin Jaap Posted January 29, 2005 Share Posted January 29, 2005 I rode my bike empty once. Put new fuel in and it ran without probs... Link to comment Share on other sites More sharing options...
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