Hi Folks, recently purchased an 02 750 ss which had no tank (see my Newbie post). I've purchased a tank which I've sealed using POR15 and am in the process of replacing the various components. I have a few questions, if you guys could point me in the right direction, that'd be great. (1) I'm replacing the fuel pump & strainer with a pattern part. There are several options on Ebay, but I've noticed that the 750ss specific pumps are more expensive, but the 800ss models are 1/3 the price. From the parts catalog the part numbers are the same, so if I buy an 800ss pump, all should be well? The exact items: 750ss pump and 800ss pump (2) From the parts and workshop manuals, there are 4 fuel line connections on the tank, two of which are connected via a y-piece connector (and to the atmosphere through the fuel cap) and the two fuel lines (feed & return). The bit I'm confused about is the fuel line routing to and from the pressure regulator. Looking at the parts manual, it looks like feed goes to the two injectors and then onto the fuel pressure regulator and which connectors to the return pipe and back to the tank. Then the 3rd connector on the pressure regulator is then connected to the 2-into-1 line from the tank. Is this correct? And if so, are things connected correctly in the image attached (I don't think they are based on the parts catalog exploded view)? In addition, the previous owner gave me a piece of fuel line which has a one-way valve (blowing on it allows air in 1 direction and not the other) in the middle of it - is this required? Really appreciate any input with this - it's been driving me mad for almost a week! Thanks, Jay.
Just in case anyone else comes across the same problem or questions: The fuel pump works fine, although has different dimensions so had to reduce some of the connecting hose lengths. The filter supplied (rectangular vs the OEM item) doesn't quite fit in the space of the SS i.e. tank, so got a pattern OEM on the way. After looking at loads of photo's for the pressure regulator (namely units for sale on ebay), the service manual and parts list - I convinced myself the pressure regulator was piped up incorrectly. I've switched the connections based on my thoughts above. It seems to run a little smoother and without the need for much choke. Cheers, Jay
Your connections look ok to me. The vent from the pressure regulator isn't normally connected to anything and is simply vented to the atmosphere. The one-way valve you got from the previous owner is for the carbed models and isn't needed on the injection ones.
Yeah I found that the vent is open to the atmosphere. I got a little confused as the vent on my blade is regulated by the vacuum pressure on the throttle bodies. As for it not needing a regulator - all the diagrams I've got for UK models show this : Which is how I've now got it plumbed in, seems to tick over okay. Not had a huge number of bikes, but all the EFI bikes I've had still had a regulator of some description to ensure you don't over fuel due the general difference between the fuel pump pressure and that applied across the injectors at differing RPMs. I know this unit is a fixed spring pressure of 3bar, which seems like an odd design (why not use the vacuum pressure from the throttle bodies?), but I'm still confident it needs one? Thanks, Jay.
Is the piece of hose with the one way valve for venting the tank? Part 41 & 42... https://www.google.co.uk/search?tbm...HodNc#imgrc=TIIcpr-Z-GwW0M:&spf=1512495914576
It very definitely needs the regulator. I was referring to the one way valve you got from the previous owner which sounds like a tank breather from a carbed model. Like you say, the regulator is set to 3 bars. This is relative to the pressure at the vent pipe. If the pipe is open to the air the pressure will be relative to atmospheric pressure. If the pipe is connected to the inlet manifold then the pressure is relative to the manifold pressure. Ducati have chosen not to use this function.
@Derek please accept my unreserved apology, I completely misread your reply and I was off on a different track! Yes I think it must be from the carb model.
