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Discussion Starter #1
Need somebody to throw me a bone.:confused:

As the title says, the bike does not want to wake up from its winter sleep.
I took off my tank this winter, and performed tank maintenance as described in the shop manual. Also put in a new Mahle filer.
While being on it, I also replaced the fuel connectors with metal ones I purchased from Carl.

Now, when I tried to switch it on today, it just didn't want to fire up. Everything else seems to be normal (I heard the pump prime), so I'm at a loss.
The only thing I can think about is the new metal fuel connectors which I had a hard time inserting them into the OEM fuel lines (I basically cut off the plastic connectors and tried to insert the new ones into the open ends). The OEM fuel lines consist of 2 lines inside each other (soft rubber outer layer and hard inside tube). The inside one had to be 'raped' to have the metal connector inserted.
After the failure to start, I took off the tank and also disconnected the fuel lines where they connect to the block. Seems to be like there was fuel dripping out of it, so fuel must make it past the new metal connectors.

Aside from that, just basic stuff happened to the bike such as changing out the spark plugs, cleaning and oiling the air filter, etc...
The metal fuel connectors are the only non OEM parts that were used.

Any ideas on how to debug this ?

Thanks in advance. So ready to ride my bike :)
 

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Your obviously getting fuel, but is it enough ? I would have thought with a fuel pump that the fuel would come out under some pressure and not just dribble out.

Check inside the fuel tank with a torch when the pump is priming. If you see bubbles or waves you have a loose hose. you will need to pull the pump out to re-attach it. (I assume you put fresh fuel in)

Do you have spark ? ie: are the new spark plugs actually firing ?

Double check that there are no kinks in the fuel line.

The above costs nothing to check before moving on to soloutions that will cost.

Good luck and let us know how you get on :)
 

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Yves, was the bike running after you did the maintenance last winter?
 

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I have just had a very similar problem! The fuel pump primed ok but bike would not run/start, I then found that I had not pushed one of the connectors quite hard/far enough into its female half! :idea: It was not evident from the side view under the tank, so I just gave them both a small push from below with a big lever, there was a click and it ran/started fine straight away! The pump did not prime for very long when the problem arose, I guessed that this indicated a badly seated self sealing coupling,ie no fuel to the injectors, all sorted now though!
 

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I had EXACTLY the same problem when I did the same thing. I replaced the fuel lines and plastic connectors with metal ones and then found the bike would start when the tank was first connected but then stall and refuse to start until the connectors were pulled out and then re-inserted, so it was a pressure issue.

Did you replace the fuel lines in the tank? If so, did you use 1/4" or 3/8"? I found that 3/8" caused leakage.

Empty the tank down to a couple of inches of fuel then with the filler cap open, observe the fuel return flow with a torch when you turn the key and it primes. Check to see if there is disturbance in the fuel anywhere else other than from the return feed coming through the baseplate indicating a leak and pressure loss. (If you have no fuel returning then that also indicates that either the feed out or in is blocked or not connected completely.)

Another thing to check - if you drain the tank and pull the pump assembly out, unscrew the allen key bolt that's mounted sideways into the base-plate to relieve pressure on the return feed and disconnect the filter from the out feed, and then remove your new metal connectors from the injector pipes and plug them in. Can you blow through them easily when connected? That will determine if your connectors are working.

Si
 

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Also make sure you didn't pinch or kink one of the lines when you reinstalled the tank.
Also I would go back and use 5/16 fuel injection line That you can get from any auto parts store instead of the OEM double layered hard tubing that came factory, with a couple of worm gear screw clamps you can make the lines a little little longer for the ease of tank removal, And you don't have to worry about that hard tubing breaking since you had to rape it.
 

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There are comments in the fuel connector thread started by Donsy where it is suggested to replace the OEM line with a new line as the OEM is not suitable to connect new fittings to.

I used a propriety 5/16" fuel injection rubber hose with no problems. Re: your starting issue I would try to run the pump with the tank lifted & hoses disconnected from the rail (into a container to verify the flow if any and the rate of fuel flow to isolate your problem.
If you have a good flow thus it is not the pump or a tank / filter issue.

My thoughts anyhow.

Murf
 

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Discussion Starter #8
This is great ! I am at the office now but will pick up some new fuel lines over lunch and as a first step swap those out tonight. Will report back.
 

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Discussion Starter #9
Changed the fuel lines to aftermarket but the bike still does not start.
Performed a spark test this afternoon on all plugs and it came back negative. No spark at all.
Since I replaced all sparks with new ones I swapped the old ones back in to eliminate the potential of bad spark plugs, but the old ones also did not spark.
Bike has a fully charged battery (is on a battery charger) and I also checked for blown fuses or loose connectors. Nothing out of the ordinary.
What to do next ?
Reminder : this is a 2008 F4 312R, if this helps any.

Thanks for your continued help.
 

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Discussion Starter #11
Correct.
And no, it's not the 'kill switch'.
 

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If you are not getting spark your coils aren't getting voltage. The battery sends power to the coils through the power relay. It's unlikely your power relay crapped out over the winter.

Check your side stand switch, gear (neutral) switch and clutch switch.

Re check all the fuses on the right side of the bike and the 40 amp fuse on the left side near the starter relay.

Since you removed the tank and the pickup sensor is connected to the main harness under the tank, check that also to make sure it hasn't come loose.
 

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I'm with Carl on this one, if all four plugs are not firing then the ECU is not telling them to fire, with the airbox removed, btw you can look down the intake ports and see if the plugs are sparking or not.
 

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Discussion Starter #14
Thank you, good suggestions.
Will have to wait another week before I can continue to explore. Just landed in Denver for a business trip and will spend memorial day at our West Coast place. Grrrr....feels like I already missed part of the riding season.:wtf:
 

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Changed the fuel lines to aftermarket but the bike still does not start.
Performed a spark test this afternoon on all plugs and it came back negative. No spark at all.
Since I replaced all sparks with new ones I swapped the old ones back in to eliminate the potential of bad spark plugs, but the old ones also did not spark.
Bike has a fully charged battery (is on a battery charger) and I also checked for blown fuses or loose connectors. Nothing out of the ordinary.
What to do next ?
Reminder : this is a 2008 F4 312R, if this helps any.

Thanks for your continued help.
Do you sdtill have the MIcrotec fitted? If you do you're a, due a major map update and b, can you send me a screen shot fo the monitor page when the engine is cranking over?

If it is not sparking then ther eis a reason for it and quite possibly i'll be able to spot it on the monitor page. Software must be open and the ike connected to the ecu etc but go that screen grab and i'll have a look.

It could be tip switch, or side stand etc, any number of things really.


Cheers

:)
 

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I'm with Carl on this one, if all four plugs are not firing then the ECU is not telling them to fire, with the airbox removed, btw you can look down the intake ports and see if the plugs are sparking or not.
you sure about that?
 
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