Replacement filter and pump after problems S4 916

Jerryd · 18-12-2021, 09:00 PM

Hi Guys

old s4 2002 916 fully good nick (in good good service) working bike bought

I have rebuilt the the fuel pump and filter in the tank.
I dont seem to be able to get the is this started.
There are 2 pipes that come out of the base of the tank.

Can someone tell me the inlet and the outlet sides? I didnt mark them when removing.

Also could I get the injector connections the wrong way around? Again did take any notice.

if i spray carb cleaner in the inlets is starts until it runs out.

Does this mean I am getting no fuel?

the bike seems sound. Electrics clean hoses good. It didnt let me down until i took ogg the tank and the injector top half. I cleaned it all thoroughly injectors etc: in a sonic bath.

thing wont start now. Can someone give a procedure of testing fuel into injectors.

to recap:

4 pipes come from the bottom of the tank. 2 small breathers and to fatter ones.
Which fatter ones are supply and return?
bike starts with spraying sp4 in inlets. does thsi mean injector are ok?

any advice please. it will be a beauty when complete as mostly carbon. engine solid and it ran really well before started my over hall. Man its quick. The gut a bought iform say do not use (choke lever i no its not but it help revs when starting). maybe a clue why is wont start now?

Darren69 · 18-12-2021, 10:11 PM

injector outlets on the tank should be marked (M) and (R) (Manda/Retourno) for send and return.

slob · 18-12-2021, 10:45 PM

if you lift the tank and open the airbox, take the filter out and hold the throttle butterflies wide open. turn the ignition on and you should see the injectors spraying into the manifolds as the system primes.

Bitza · 19-12-2021, 08:15 AM

Well the most obvious fault would if you had the feed and return pipes the wrong way around. The return pipe comes off the throttle body assembly after the pressure release valve, (the feed pipe goes direct to the injectors) trace the return pipe back to the tank. Turn the ignition on just to prime the system then turn off) and then disconnect the return pipe, if the fuel is under pressure then the pipes are the wrong way around. Beware if this is the case because you can cause the release valve to jam closed, easy to replace 3bar universal type. Best of luck Bitza

Dukedesmo · 19-12-2021, 03:50 PM

As above, Mandata (out) Ritorno (in) but, if it's the same setup as a 916 then it doesn't matter as the pressure regulator is in the tank so it is effectively just a loop of pressurised fuel so it works either way, however if the pressure regulator's by the injectors then it will be important to get it running right and the likely cause.

Breathers are usually, overflow from the filler and air in and you probably 'T' them together to exit out the bottom of the bike incase of an overflow.

If you connect (electrically) the injectors the wrong way round then it won't run, same with the coils but if it starts with a spray then the spark is OK so coils correct.

18-12-2021, 09:00 PM	#1
Jerryd Registered User Join Date: Mar 2021 Location: Watham Cross Bike: S4 Posts: 29	Replacement filter and pump after problems S4 916 Hi Guys old s4 2002 916 fully good nick (in good good service) working bike bought I have rebuilt the the fuel pump and filter in the tank. I dont seem to be able to get the is this started. There are 2 pipes that come out of the base of the tank. Can someone tell me the inlet and the outlet sides? I didnt mark them when removing. Also could I get the injector connections the wrong way around? Again did take any notice. if i spray carb cleaner in the inlets is starts until it runs out. Does this mean I am getting no fuel? the bike seems sound. Electrics clean hoses good. It didnt let me down until i took ogg the tank and the injector top half. I cleaned it all thoroughly injectors etc: in a sonic bath. thing wont start now. Can someone give a procedure of testing fuel into injectors. to recap: 4 pipes come from the bottom of the tank. 2 small breathers and to fatter ones. Which fatter ones are supply and return? bike starts with spraying sp4 in inlets. does thsi mean injector are ok? any advice please. it will be a beauty when complete as mostly carbon. engine solid and it ran really well before started my over hall. Man its quick. The gut a bought iform say do not use (choke lever i no its not but it help revs when starting). maybe a clue why is wont start now?

18-12-2021, 10:11 PM	#2
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,023	injector outlets on the tank should be marked (M) and (R) (Manda/Retourno) for send and return. __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

19-12-2021, 08:15 AM	#4
Bitza Bronze Member Join Date: Jul 2006 Location: Poole Bike: M900ie Posts: 470	Well the most obvious fault would if you had the feed and return pipes the wrong way around. The return pipe comes off the throttle body assembly after the pressure release valve, (the feed pipe goes direct to the injectors) trace the return pipe back to the tank. Turn the ignition on just to prime the system then turn off) and then disconnect the return pipe, if the fuel is under pressure then the pipes are the wrong way around. Beware if this is the case because you can cause the release valve to jam closed, easy to replace 3bar universal type. Best of luck Bitza __________________ Bitza

19-12-2021, 03:50 PM	#5
Dukedesmo Registered User Join Date: Sep 2010 Location: Leics Bike: M900 Posts: 2,844	As above, Mandata (out) Ritorno (in) but, if it's the same setup as a 916 then it doesn't matter as the pressure regulator is in the tank so it is effectively just a loop of pressurised fuel so it works either way, however if the pressure regulator's by the injectors then it will be important to get it running right and the likely cause. Breathers are usually, overflow from the filler and air in and you probably 'T' them together to exit out the bottom of the bike incase of an overflow. If you connect (electrically) the injectors the wrong way round then it won't run, same with the coils but if it starts with a spray then the spark is OK so coils correct. __________________ M900, 916, LeMans II.

18-12-2021, 10:45 PM	#3
slob . Join Date: Jul 2003 Location: East London Bike: Multiple Monsters Posts: 9,712	if you lift the tank and open the airbox, take the filter out and hold the throttle butterflies wide open. turn the ignition on and you should see the injectors spraying into the manifolds as the system primes.