Wildguzzi.com
General Category => General Discussion => Topic started by: Muks on August 10, 2024, 10:54:11 PM
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I own a Moto Guzzi v9 roamed which has done 8000 km, yesterday I left home and after traveling 2 km the engine suddenly died! I towed it back home, starter motor works fine. Checked spark on plugs it’s fine, checked fuel injection the spray is fine, emptied the fuel tank petrol has no water or any other impurities, no blown fuses!
What could be the problem?
Thanks in advance 🙏
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Off the top of my head, it has been the cam position sensor when it has happened to me. No warning, suddenly no spark but it could be an open in the wiring as well.
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Have you checked the fuses?
My B1100 quit on me and I eventually traced it to a faulty speed sensor that took out one of the 2 (yes two) supplies to the ECU
My copy of the V9 wiring diagram shows two feeds like the Breva
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Go into dash and see if Diagnostics says anything, designed to show errors.
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Making some very broad assumptions, that your quality of spark is good, there are only 2 things that can kill the motor.
1. Timing is bad
2. Compression is bad.
Has the motor ever been hard to start before? Particularly, has it been harder to start hot than cold? If yes, check your valve clearance. (check it in any case)
A timing sensor can't change timing, it can only fail to report which results in no spark so that seems unlikely.
How many miles had you run previously on this particular tank of fuel? What is the condition of the spark plugs?
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I deleted my suggestion about a poor battery after I reread the post. Didn’t realize that the starter motor would run.
So, if the battery works, and the spark plugs are properly gapped and not fouled, how about the plugs, plug wires, and coils? My coils went bad on my V7 II at 40K miles, but I imagine they can go sooner, eh? And the plug wires—shared across many earlier V7 up through the V9–are known to go early for some. Time to pull out the multimeter?
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I re read the original post and I see that it does have spark, I originally misread and thought it didn’t. I think the title saying it wasn’t firing led me to think wrongly. Tight valves? Seem like you’ve checked most everything
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Just had a completely random thought, it's not something like
Sidestand switch or kill switch is it
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Just had a completely random thought, it's not something like
Sidestand switch or kill switch is it
Not random at all. If it "suddenly" quit, that is a likely scenario. Something is not telling the computer that all is well. :smiley:
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I tried with new plugs also but same result!
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One of the first things I do when faced with this sort of thing, is determine if both sides have died or one.
In your case it’s both sides, so…
It’s not plugs
It’s not compression (unless you’ve broken a camchain… :cry:).
It’s not injector..(notice I didn’t say “injectors”…?)
Not plug leads
etc…..
It couldn’t be something like the stupid clutch or sidestand cutout switch could it ?
The reason for the foregoing is that the above maladies (and a myriad of others), will not manifest on both sides simultaneously in the real world. You need to look at something that feeds BOTH sides.
It’s always nicer if you lose a single side, then you can swap components side to side, to see what shifts the problem.
Take the plugs out and crank the starter with your thumb over the plug hole as hard as you can, every SECOND revolution should try to blow your thumb away from the hole (indicating compression), if this is not evident, you may have a camchain problem that has allowed the valve timing to slip. A more definitive test for compression loss (short of a tester), is to unwind the plug/s until 3 or 4 threads are still engaged, put the bike in 6 th gear and rotate the rear wheel, you should hear a definite “puff” sound as the piston rocks over.
Was there any mechanical clanking when she stopped ?
Do you have access to Guzzidiag ?
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In fact when stopped I tried to start the engine and it showed the sign of starting but engine won’t fire and slowly after many attempts the symptoms vanished!
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In fact when stopped I tried to start the engine and it showed the sign of starting but engine won’t fire and slowly after many attempts the symptoms vanished!
What the hell does that mean ?
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I don't understand why you don't use the diagnostics and fix issue. Read book, push buttons, and see.