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Discussion Starter #1
Hey all,
Hope you can assist I replaced the SPU started it once, it ran perfectly. Turned it off when I went to start it again the battery was flat, replaced the battery with a new one. Still won't start.

The symptoms:

When the Ignition is turned on the sound it used to make has changed.
When it was turning over it back fired a few times
Can smell the fuel

Any ideas what this might be?
 

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does the fuel pump make a squeal instead of a hum? But I don`t think you would smell gas though if the pump failed. the fuel goes out the bypass instead of through the pressure regulator and to the rail.
 

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fuel routing?

cdamb;
doesn't matter how you hook the fuel lines up.......
it comes out of the pump, goes through the fuel rail and THEN to the fuel pressure regulator

it going to go clockwise or counter clockwise.....pressure is the same........don't tell MV with their color coded connectors:stickpoke:stickpoke

kind of shows what they know about fuel injection......why isn't the vacuum operated pressure regulator connected to manifold pressure?
it would equalize the spray pattern:jerkoff::naughty:

:popcorn:

:f4::brutale:
 

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Discussion Starter #4
The sound it now makes is hard to explain, it just sounds sick would be the best way to describe it.
 

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If the bike turns over and doesn't catch, and everything else seems fine, I would suspect the fuel pump or fuel filter. As long as you don't see fuel your hoses aren't leaking, but smelling fuel is not right either.
 

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Discussion Starter #7
I replaced the SPU as the last one was faulty, common fault with the origainal SPU.

Have checked the cables, no leaks.

I am tempted to switch the fuel Cables over to see if that makes a difference.

Don't understand why it started fine then after the battery failure it wont start.
 

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I replaced the SPU as the last one was faulty, common fault with the origainal SPU.

Have checked the cables, no leaks.

I am tempted to switch the fuel Cables over to see if that makes a difference.

Those are called Fuel lines, the cables are a completely different thing. :naughty: Swapping them over wont make a difference mate.

Don't understand why it started fine then after the battery failure it wont start.
The fuel lines I am talking about is inside your fuel tank mate. Open your fuel cap and turn the bike on, see if you see bubbles inside the tank as you turn the bike on.
 

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Discussion Starter #9
Donsy I think you might be right as far as the Fuel line, There is no damage however I think the way the fuel lines are sitting when the tank goes in it could be crimping one or both of the fuel lines.
 

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Discussion Starter #12
Ok will shine a light into the Tank and see what I can see. Thanks for your help, will let you know how I get on.
 

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Couldn't see if any connection's were broken, I think your right. Will need to pull the Pump out to check it. Needs a service so will get Trooper Lu's to look into it. Thanks for your help, will let you know.
 

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Couldn't see if any connection's were broken, I think your right. Will need to pull the Pump out to check it. Needs a service so will get Trooper Lu's to look into it. Thanks for your help, will let you know.
From what you say it sounds possible that the fuel lines may have been incorrectly routed that,s all, you have to get em sitting right. Saying all that though I would have thought It'd be hard to kink em as they are so thick.

FWIW the fuel filter can be replaced very inexpensively too, there are exact filters like this available here in the UK at a mere fraction of the price of the genuine MV part, possibly if you do a search you will find a part number and make.

The Knurl will steer you in the right direction for the big 'O' ring seal that is located on the base of the casting, that 'in all honesty' you really should replace, don't forget to use a smear of silicone grease on it when replacing the assembly.

Hope you eased the assembly out of the tank with 3 allen screws or threaded bolts screwed into the 3 threaded holes located in the
flange.

A lot of folk use a screwdriver as they don't realize what the 3 threaded holes are there for. Just screw 3 bolts in and tighten em up equally and 'Hey Presto' the assembly pops out easily and squarely without any damage whatsoever.


:popcorn:
 

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Yes I did get the order wrong. :banghead: So if there was compression on one of the fuel lines when the tank was replaced then it would hinder the flow of fuel.
 

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cdamb;
doesn't matter how you hook the fuel lines up.......
it comes out of the pump, goes through the fuel rail and THEN to the fuel pressure regulator

it going to go clockwise or counter clockwise.....pressure is the same........don't tell MV with their color coded connectors:stickpoke:stickpoke

kind of shows what they know about fuel injection......why isn't the vacuum operated pressure regulator connected to manifold pressure?
it would equalize the spray pattern:jerkoff::naughty:

:popcorn:

:f4::brutale:
I always wondered why there was no vac line on the regulator. I assume you can tune around it, but seems like it would be much more stable to pull pressure down based on vacuum.
 
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