Paso fuel pump replacement?

lucky · Post by **lucky** » Fri Jun 16, 2006 4:23 pm

Are there any reasonable alternatives when needing to replace the fuel pump on an 88 750 Paso? Will any other newer models fit?

Mike

delagem · Post by **delagem** » Sat Jun 17, 2006 3:55 am

Can anyone shed any light on running the Weber carb with no pump?

I took the pump out of my bike when I got it, and plumbed the carbs directly from the tank. I ran a loop of fuel line up forward under the headlight, so as to have a fuel petcock that was accessible. (I got the idea from someone here on this site, but I don't know who to give credit to!) I have run the bike all the way down to about 1 quart of fuel remaining, without fuel starvation issues.

For the record, I don't have the stock carb, I have a set of Dellortos. And I don't have a stock tank, my 750 Paso has a 907 tank and fairings on it. Not sure if this makes a difference.

750pheonix · Post by **750pheonix** » Sat Jun 17, 2006 9:41 am

as long as it pumps it'll do the job... however, it seems there are ways to make the combination of the weber and it's pump work better together.

if you can get a pump with a built in regulator that probably be good, these are fairly common. set the pressure somewhere between 3-4 psi.

Webers are supposedly best mated to a pump that provides large volume flow without pulsing.

the only benefit the original fitting has is it's small size.

persempre907 · Post by **persempre907** » Sat Jun 17, 2006 4:26 pm

The difference beetween the tank of 750 and 907 is that on the 907 the fuel pump is into the tank, rather than out as on 750.
I also have heard that the fuel pump wouldn't be necessary because however the engine works fine.
Someone else has tried to take the fuel pump out?
Any issue?
Ciao

lucky · Post by **lucky** » Mon Jun 19, 2006 2:38 pm

Well,

the bike in question here has mikuni CV or constant velocity carbs on it as I am told.

Any help as to whether the fuel pump is absolutely neccessary or if there is a cheaper alternative?

Mike

Post by **paso750** » Mon Jun 19, 2006 2:44 pm

Mike,

as Ducati developed the Paso I`m sure they had some intention behind this. Maybe its because the fuel line is rather long and has a slight upwards curve if I remember correctly. However, every fuel pump will work. I don`t see any reason why it shouldn`t.
Kawasaki, Honda etc. I`m sure that works although you`ll maybe need some small mods to mount it.

Gerhard

btw, that reminds me I had a spare once, but I`m not sure I still have it. I`ll check - I`m getting old

Post by **jcslocum** » Mon Jun 19, 2006 3:13 pm

I have Dellorot's on my Paso with NO fuel pump. Works great. The Weber seems to have been mounted much higher and because it was an adaptation of an automotive carb, the fuel pump is required.

I think you can run without it if you have mikuni's.

Paul · Post by **Paul** » Fri Jun 30, 2006 6:31 pm

Dalagem,

You're probably referring to my post where I put a Briggs and Stratton fuel tap under the headlight as the fuel in my tank used to drain via the carbs over time (even with new needle valves fitted). I have twin Dell'orto PHM 40s and without the standard fuel pump it suffers from fuel starvation above about 5,000 revs.

Paul

delagem · Post by **delagem** » Fri Jun 30, 2006 7:57 pm

Yes, that's the one! I even got the Briggs and Stratton version of the fuel tap, and it works great! I don't have any trouble with fuel starvation though; what are your symptoms?

delagem · Post by **delagem** » Fri Jun 30, 2006 8:00 pm

Yes, that's the one! I even got the Briggs and Stratton version of the fuel tap, and it works great! I don't have any trouble with fuel starvation though; what are your symptoms?

Paul · Post by **Paul** » Fri Jun 30, 2006 8:18 pm

Dalagem,

When I bypass the pump it doesn't get to the point of cutting out, it is just a lack of power and it doesn't want to rev (from around 5,000 revs I think. I did this about two years ago). If I put the pump back in line it pulls well and rides nicely. So I decided to leave the pump in.

It could be something as silly as a partially blocked fuel pipe or filter, and the pump is masking it by supplying enough fuel. I didn't think of that until I was typing this reply. Maybe next time I want to play I should check in the tank. I replaced the flexible pipe when bypassing the pump. Do you know if there is a filter in the tank on a 750 ?

Paul

delagem · Post by **delagem** » Fri Jun 30, 2006 8:37 pm

I'm sorry Paul, I don't know anything about a stock 750, my bike is a frankenstein mix of 907 and 750; not sure what's original and what's been modified.

I do notice a lack of power on top on mine, perhaps I've got a fuel starvation problem and don't know it? I remember an article by Kevin Cameron on how to calculate fuel flow, guess I gotta find that now! Geez, thanks Paul!

Post by **paso750** » Sat Jul 01, 2006 9:53 am

Paul,

there`s a small wire filter in the petcock. If you remove it you`ll see it. But that filter is not very fine and probably mainly stops any rust or other bigger particles to get in the fuel line.

G.

persempre907 · Post by **persempre907** » Sat Jul 01, 2006 10:25 am

Hi everybody,
I have the LT Snider guide.
He says that the fuel pump can be replaced by the Ford Ranger 3.2 model for carburated engines and by a Ford Mustang 5.0L model for injected bikes.
I don't know if there are the same: those cars don't are sold in Italy!!
But, if you need to replace the pump, you could try with those even if, as Gerhard tells, all pumps will do the same work.
Ciao