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Fuel pump fault??
maccmike - 12/8/12 at 10:12 PM

Hoping for some expertise from zzr1100 wiring guru's.
Fuel pump doesnt prime with ignition on anymore, used to.
Fitted new pump relay but no luck.
Hot wired pump, works fine.
With engine running (rough) I can feel it pump every 2 seconds or so.
The powered black wire between the relay and pump.. if I bypass this with 12v feed the pump works fine.
So, Im requesting suggestions.
Could the starter solenoid or ignitor unit be a cause?

[img] c model
c model [/img]

maccmike - 12/8/12 at 11:09 PM

Heres the haynes manual fuel pump circuit

[img] Description
Description [/img]

Peteff - 13/8/12 at 07:35 AM

Does it pump/prime when the starter button is pressed? a lot of carb engines work that way

maccmike - 13/8/12 at 07:55 AM

thanks for the reply, it does yes but its a really poor prime.
It used to prime with just the ignition and it would prime properly.

maccmike - 13/8/12 at 08:46 AM

bumping all guru's

daviep - 13/8/12 at 09:41 AM

quote:
Originally posted by maccmike
thanks for the reply, it does yes but its a really poor prime.
It used to prime with just the ignition and it would prime properly.


I don't understand what you mean by this, either it starts pumping or it doesn't? Are you checking it with the outlet open and in to a jar? If not then the pump may only stroke once or twice if the lines and carbs are full of fuel. So it's best to disconnect the hose from the discharge when trying to diagnose, either that or substitute the pump for a bulb when testing the electrical side.

If the pump is ok with the discharge removed then reconnect and remove from the carbs to test for a blockage between pump and carbs.

Cheers
Davie

maccmike - 13/8/12 at 09:50 AM

it doesnt go pump pump pump pump etc with empty fuel lines. normally couple of pumps per second where as now its only pumping maybe once every 2 seconds with empty fuel lines.

daviep - 13/8/12 at 10:28 AM

Do you have a multimeter? If so check whether the voltage at the pump is 12v when it is trying to pump. If it is or very close then you can stop looking for electrical faults.

I would definatelty disconnect the outlet from the pump and get it pumping in to a jar so that you can be sure the pump is working and getting a good supply from the tank. It should pump

Do you have filters if so where?

Cheers
Davie

omega 24 v6 - 13/8/12 at 11:42 AM

Go with Daveie p's instructions first. If there is voltage and no drop in voltage then suspect the pump and or blocked pipes/filters.

If there is no voltage then meter the wires for continuity one by one. If they are Ok suspect the relay itself. Meter what you can on it.
It looks to be a dual circiut on the relay. i.e. very similar to the old vauxhall cavvy setup where ( after priming of course ) if the pump is not getting a signal from the coil then the relay cuts out and stops fuel from pumping ( In the event of an accident an the ign being left on with the engine not turning the pump stops pumping.)

Also check the output fuel pressure. Looking at the diagram I'd assume that the pump has an internal over pressure limiting valve. If its gone and there is little or no pressure to pump the fuel then you might have a poor injector pattern/lack of fuel to burn. ( it is injection I assume?)

maccmike - 13/8/12 at 11:58 AM

ok cheers chaps.
I do have a multimeter but I borrowed it out!! probably never to be returned)
Il acquire another today.
Im cleaning the carbs at present, so when Iv put them back on Il check pump voltage.
The relay is a brand new item as its almost always the fix for pump problems.
Its carb not injection.
Before the fault, with just the ignition on the pump would prime as pumps should.
Since then, it only pumps every couple of seconds only when the engine is turning over.
The exhaust doesnt smell fuely enough so suspect starvation.
All plugs and coils have spark.
Will do as instructed and get back to you.

maccmike - 13/8/12 at 03:01 PM

Rebuilt cleaned carbs, runs perfect! ??
Absolutely baffled by that.
Pump still aint priming which it honestly has done since Iv owned for over a year.
Il have to see how I get on, thanks for your advice though guys.

maccmike - 16/8/12 at 04:18 PM

UPDATE.

The previous brand new fuel pump relay failed again, bought 2nd hand pump and relay (in case it was the pump causing it to eat relays) and it wad idling, revving sweetly, went for a run around the block for a shakedown (not been out since feb). Relay failed again, absolutely hot to the touch! Relay had melted slightly in places.

What should I look for? ignitor/rectifier/regulator/other.

Advise much appreciated.

Mike.

maccmike - 16/8/12 at 04:53 PM

bump

maccmike - 16/8/12 at 06:28 PM

bump

omega 24 v6 - 16/8/12 at 07:18 PM

Well the relay will be warm to touch. Not as warm as to burn you but quite warm.
Have you metered the voltage?? you really need to, for peace of mind.
Other than that ( as its not blowing the fuse) then check that all the contacts, in the relay base, have a tight grip on the relay terminals ( slack connections allow arcing and heat buildup/ melting can and will occur.)
If they are tight make sure the wires are well connected/crimped into the relay holder ( give them a tug and see if they come away ( again a bad connection etc etc).

maccmike - 16/8/12 at 09:49 PM

cheers for that mate.
It really was very hot, too hot to handle, literally!.
checked all numbers and they were within tolerences.
Will do as you suggest tomorrow.
Getting very close to just putting a switch on the pump and getting rid of the relay..