9 replies to this topic

[Philminim]

Does anyone use something like this? (see my recent project post for problem)

https://www.turbosma...es-an-fpr-work/

Do you ever connect the env to the manifold vaccum or just leave it open to atmosphere pressure please?

 

ta

 

 

[IronmanG]

Mines open
Plus I have a swirl pot in between the lp and hp pumps
What fuel tank are you running? A standard position tank?

[sonscar]

If the engine is injected as standard there may be a pressure regulator already on the fuel rail.The regulator is usually referenced to the manifold vacuum so as to keep constant pressure across the injector.Guessing at the problem is risky.The injectors could be stuck open etc.Have fun,Steve..

[Philminim]

Thanks both. I have a one gallon tank (hillclimb) with gravity feed to a free flow filter then injection pump (Bosch) as others use on here, then to the fuel rail. It's an r1 2005 injected.

[Philminim]

Was debating fitting a solid state pump before injection pump.idle and revs are fab..just misfires under load.

[Philminim]

This is the problem in a bit more detail.


Most pressing...
Idle is fine and car revs freely..but under load misfires badly and has top speed of around 30mph..
I am guessing this is a quick fix...I am thinking ...
Either is because the fuel tank gravity feeds the high pressure fuel pump and not enough fuel gets to pump..so without load it's fine, with load it isn't.....my fix for this would be to install solid state pump 4-5psi pump between the tank and filter to give more consistent delivery to the hp pump.

Or
The fuel return pipe from injector rail to tank is not large enough diameter and it's blowing the fuel rail open and drowning the engine..

Else something wrong on bike engine.. sensor etc.

I can't see it being anything other than quick fix but how best to diagnose which quick fix is needed?

[Philminim]

update...

 

facet solid state pump fitted. so my fuel chain is now - 

 

gravity feed 12mm | filter | to facet 8mm | filter | bosch 100psi pump (recommended on this forum) through to injectors | fuel return direct to tank

 

When I test ran the fuel pumps together, I had forgotten to put the fuel filler cap on and the return which is in my filler neck was sufficient pressure to blast out of the top about a foot. 

 

On startup, car will now not rev at all and cuts out, whereas previously it was revving very well without load

 

I think this lends weight to me needing to reduce pressure at the fuel return by fitting either :

1) a fuel return swirl pot before the feed back into tank

or

2) a fuel pressure regulator after the HP pump

 

Question is - which? and if a regulator, what pressure should I set it at? (bear in mind r1 2005 already has a fuel pressure regulator I believe?)

 

thoughts?

ta

[Northernpower]

Mis post

Edited by Northernpower, 15 March 2022 - 12:07 PM.

[mini13]

from a reach the R1 fuel pressure is 3 bar (43psi)  its not clear if its manifold referenced or not,

If your not referencing it and it should be you'll be running rich under idle and part throttle.

if you are referencing it and shouldnt be then the opposite will be true.

 

I think the added pump should not be needed, but if it is there then it should be feeding a swirl pot and acting as a " mini fuel tank" if its just in line you''ll outstrip the flow of the solid state pump

[Philminim]

Thanks. All good stuff there.

Yea reason for facet was I figured injection pump outstripping gravity feed.

I only gave it part throttle but was defo more lumpy than before.

The build dvd give no mention of manifold reference requirements or otherwise. Just saw a tank, injection pump straight into fuel rail on it

I am so close I can taste it..it's maddening!:)