That’s good! 
Very lucky having all the bits in the tank.
The fuel hoses are probably a bit tired, mine were, however changing the ones with crimped banjos isn’t quite straightforward, unless buying new ones from the likes of Gutsibits.
Yes, it looks like the fuel pressure regulator is an easy swap. The fuel lines actually seem in quite good condition. They are also the more modern standard saej30r9 as opposed to the older j6. I am told these withstand the more aggressive modern fuels better. But like you say they are quite old. On the fence about replacing them. The fuel that came out of the filter was a little muddy, but not terrible. Slightly reddish tinge.
Cobbled together a little test for the fpr whilst the tank is off. Attached a Makita battery compressor to the fuel line going into it. Set the pressure to 46psi to see if the regulator would open at 43psi and let the air through. On starting the compressor I had air immediately coming through the Vacuum reference port and the fuel tap. Guessing the diaphragm is shot in the fpr.
Possibly, the replacement adjustable unit I fitted works by allowing flow to the throttle bodies from the pump, spilling the excess pressurised fuel into a return line to the front of the tank, in other words it doesn’t prevent flow, it simply allows up to your preset (adjustable 0-10bar, set to 2.5) and bypasses any excess (external Bosch pump is nominally 7bar) to the tank return line.
May be different on yours if the pump and fpr are both tank mounted.
The pump is frame mounted the fpr is mounted directly to the front underside of the tank. It is connected by a fuel line to the exit side of the fuel filter. There is a junction there that sends fuel to the fpr and to the injectors. The tank mounted fpr sends fuel directly back into the tank when opened due to pressure.
Thing is, it was allowing air through at about 1bar or less. So would have been drastically lowering the fuel pressure. Or at least that’s my understanding.
An interesting unrelated side discovery is that the manual fuel tap Def does not work! Screwed up or down the air the fpr was sending into the tank came straight out the fuel tap. I note that other people have had issues with these.
Interesting!
I’ve not had a post-1998 bike to look over, but it sounds like yours is an improvement on mine.
You’d not think that the difference between air and liquid (albeit a volatile one) would provide more back-pressure from the injectors to the fpr? Just a thought.
Sort of! It appears that much depends on the random selection of parts. I mean that looking around it appears that there are cali ev’s from the same year that have diferent set ups. I think some early 2001 ev’s might have had internal pumps etc.
yes you might be right about the diference between air and liquid and back pressure. My thinking is that the spring in the fpr should open (is rated to open at 3 bar either way. And given that air is pressing through at a lower pressure ( through both the tank and the vacum reference spigot) something must be up. Anyways for better or worse I have ordered a new pierburg one. link below if anyone is looking for one.
Hi Blubbles your throttle cable outers should not move in and out. Is you fuel pump in the tank with the filter if so you will not have an external one. Regarding the FPR (Fuel Pressure Regulator) located in the front and under the tank this item has a two way thread left hand and right hand and is a pain in the butt to get right.
Hi Richard, my system has the fuel pump outside the tank on the left side of the frame.I was about to try and undo the fpr housing and thinking it looked awkward but i noticed a circlip at the bottom of the housing. Removing that allows you to remove the fpr without having to remove the housing.
That’s certainly a different setup to my earlier model, the fpr is one-piece and discontinued, with a return line to a spigot at the front underside of the tank. At least with yours there’s the ease of undoing a clip and popping a fresh fpr into the housing, far better idea 
Hope it all goes well for you and is the answer.
Hi mate it is different to my 2005 model. What is no.1 (the fuel pump ?) - no. 8 is the fuel filter. no. 14 and no. 3 ? The under side of my fuel tank (behind the FPR) has an extra thin pipe push fit attached to the tank and runs all the way down to were the main stand is and probably an overflow pipe or breather ? I wonder if your injectors are semi-blocked.
1 is the fuel pump. You may well be right about the injectors. But the fpr for sure wasn’t right. So I’ll replace that, the fuel lines and the filter and see how it goes from there.
14+3 in the image are just the clamps to hold fuel filter + pump.
Based on rather too much experience with BMW K100s that have been stood for too long, two things:
- the fpr tends to throw its toys out of the pram (you’ve found that). They also get weaker with age.
- the fuel injectors get clogged up.
As regards the fpr; it is the same one as fitted to a shedload of 1983 to (approx) 1995 K-series BMWs so don’t limit yourself to buying one specifically for a Guzzi.
The fuel injectors are a bit more of a pain. You can get them professionally cleaned and reset (tends to be a bit expensive), but before even considering that route there’s a couple of things you can do yourself. The first and easiest (!) is to dismount them and leave them to soak in a dish of carb cleaner for a day or two. With any luck, that will break down the crud inside the injector. The second step is to replace the atomiser filter and both o-rings, both of which are genuinely user-serviceable. There is a part number on the side of the fuel injector which will tell a decent autoshop which overhaul kit is required.
Honestly, if the bike was standing for that long, I think I’d buy the overhaul kits first, then strip the injectors and leave them in the carb cleaner for a couple of days.
Thanks, I have been merrily ignoring the injectors 
… in the hope that I don’t haver to go that far. I knew I will but denial keeps me going. The Fpr and new fuel lines are in the post. I might just pull the injectors out while I’m waiting…
If you overhaul the injectors, I can guarantee you’re going to be looking at the atomiser filter thinking ‘how the h£ll does that come out’ 
Youtube video. Annoying voice but…
Gives you the basics.
ECUP8(I_GB)MAJ02.pdf (3.6 MB)
This may be of interest. Cant remember source.
That’s an excellent resource, thank you! 
Thanks for that DaiG that’s really helpful. For a minute I was thinking what is he doing to that injector … then it all made sense!
This is really helpful MR P thanks. Much more detailed than the one I have.