V11 Sport 2001 intermittent stalling

[Gio]

I'm not sure I would re-locate the pump at this stage ... mine was re-located to a similar location to yours is now (ie above the spine) and has been problem (vapor-lock) free since - but I would try to distance that fuel line from the left cylinder and/or heat shield it.

[Chuck]

FWIW, this is used on aircraft to insulate fuel lines.

http://www.aircraftspruce.com/search/search.php?s=FIRESLEEVE&x=0&y=0

[Tinus89]

(...)

 

Don't discount bad plugs

 

I have seen a couple of times where the relay bases look just fine but a connector hasn't clicked in properly, when the relay is inserted it makes intermittent contact, easy to check just push on each one with a small tool.

 

One time when I had a bad regulator the bike would rev up, cut out, slow down a bit and repeat in a pretty consistent cycle but idled and low revs just fine.

I figured the ECU was cutting out on over Voltage to protect itself.

 

 

Is there any way to check the plugs? Measure resistance? I've ensured they are properly gapped, they are in good condition and equally colored as well.

 

I've checked all relay base connections one by one after I squeezed them together one by one again.

 

I am worried about what you just described on the regulator, as this really resembles the behavior I am getting. I know it should do 13.8-14.4v at 3k rpm, but could we agree what the max should be at 6k rpm? Then I can check that.

 

FWIW, this is used on aircraft to insulate fuel lines.

http://www.aircraftspruce.com/search/search.php?s=FIRESLEEVE&x=0&y=0

 

I will relocate the fuel line which is close to the cylinder and see if I can source anything close to that to put around it here in the NL.

 

So, in short, my plan of action: 

- Relocate and if possible isolate fuel line.

- Reinstall fuel tank and warm up bike. 

- Rev at 3k and 6k rpm to check voltage.

- Drive, with special focus on getting the bike hot (warming her up in 15min, then letting her idle outside for say.... 10min? Is that too long? I want to prevent overheating...). Then drive again (close to home) to see if the issue returns.

- Maybe when she is really hot, again measure at 3k and 6k rpm?

 

If she does fail again, bring her home, and again measure voltage when she cuts out. Would you say a normal multimeter would suffice, or would that not be able to pick up the spikes in voltage? I want to be prepared.

[czakky]

I caught my regulator before it fried my battery and it would be around 14v at 3k but it would just keep climbing up to atleast 19v but it was worse when warm. Honestly I didn't have any running problems but that could be due to my new (then) Odyssey.

[MartyNZ]

If she does fail again, bring her home, and again measure voltage when she cuts out. Would you say a normal multimeter would suffice, or would that not be able to pick up the spikes in voltage? I want to be prepared.

The workshop manual says: The regulator has been calibrated in order to maintain the battery voltage at a value between 14-14.6 Volts.

V11 Alternator Regulator.pdf

[Kiwi_Roy]

It also includes the Voltage drop in the headlight circuit which can vary quite a bit.
 

[Tinus89]

So, update:

 

- Reset valves to 0.15 and 0.20. Right side is louder then left, but still acceptable. She revs better and sounds louder (=better ).

- Replaced 30A fuse holder for a new one rated to 35A, with a new 30A fuse.

- Re-routed fuel line away from cylinder.

- Installed new fuel pump manufactured by NASA:

 

 

Just kidding . Covered the intake line and fuel pump in reflective aluminium taping.I could not get my hands on anything better and this will at least do a good job at keeping out the heat...

The idea behind only doing intake line and pump, is that after the pump the pressure will be higher (~3bar), so the evaporation point goes up significantly.

 

[MartyNZ]

The idea behind only doing intake line and pump, is that after the pump the pressure will be higher (~3bar), so the evaporation point goes up significantly.

You are correct that the boiling point goes up with increasing pressure. The volatile compounds in your fuel will boil at 40°C (ish) in your tank at atmospheric pressure. The boiling (vapour lock) temperature is lower in the induction side of the pump, between the screen and the pump, and higher on the pressure side, so you have insulated the right part of the fuel system.

Fuel will boil when its vapor pressure exceeds atmospheric pressure. Boiling temperatures increase with increased pressure, and decreases with decreased pressure. The different hydrocarbons in your fuel have boiling points ranging from as low -10 to over 200°C. The boiling point of your fuel will vary from season to season, the temperature, and the pressure drop in the fuel sustem. I imagine that a partially blocked fuel intake screen might make the pressure drop greater, and tendency to vapour lock worse.

[Kiwi_Roy]

Take a close look at this schematic

 

http://www.thisoldtractor.com/guzzi007/schematics/1999_V11_sport.gif

 

Take a pencil and draw a line down the left hand side of the ECU and across the bottom of items 55,54,53,52,51,50 and then

up around the bottom of Fuse 1 and 2

 

How many wires did you cross?

Only three, what do they do?

 

The first one at connector 58 is just the signal to the Tach, it could be left off and the only thing is the tach would stop working.

 

The third one is battery positive to Fuse 1 and 2, obviously that's important but very easy to check.

 

The second one is the only one of any significance it tells the ECU to turn On, if that one is alive and you have 2 good relays chances are the bike will run.

Wouldn't it be handy to know if it's alive or not?

 

So what am I getting at?

[Tinus89]

Take a close look at this schematic

 

http://www.thisoldtractor.com/guzzi007/schematics/1999_V11_sport.gif

 

Take a pencil and draw a line down the left hand side of the ECU and across the bottom of items 55,54,53,52,51,50 and then

up around the bottom of Fuse 1 and 2

 

How many wires did you cross?

Only three, what do they do?

 

The first one at connector 58 is just the signal to the Tach, it could be left off and the only thing is the tach would stop working.

 

The third one is battery positive to Fuse 1 and 2, obviously that's important but very easy to check.

 

The second one is the only one of any significance it tells the ECU to turn On, if that one is alive and you have 2 good relays chances are the bike will run.

Wouldn't it be handy to know if it's alive or not?

 

So what am I getting at?

 

This will have to wait until monday... Then I can print the schematic in A3 format at work and follow the lines - impossible on the screen.

 

 

MartyNZ - Interesting read! But if boiling starts at 40deg C, does that mean the fuel composition is different in e.g. African countries, because heat can rise up to and above 40deg?

[gstallons]

Fuel ( gasoline in this case ) is different everywhere .

[luhbo]

Tinus, you say you're in the Netherlands. That's at sea level. You won't see any vapour lock as long as ambient temperature is below 35°C, even then only under really bad conditions like Stop&Go in town or so. You can recognise it at a squeaking or just strangely high reving fuel pump. Keeping the petcock open and cycling the pump several times with the kill switch usually solves this problem (which you don't have anyway).

For me your story sounds like a dying phase sensor. Unfortunately you cannot realy check them. In case you want to try a new one look for similar car parts from Fiat e.a. Usually they are all the same, just the cabel length differs.

The blown manifold: next time your engine acts weird you better keep the throttle a tad open, using the "choke lever" for instance. That helps taming the Bang.

[Chuck]

Uhhh, back in the day at Bike Week (Daytona Beach) several volunteers brought ice to the Guzzi demo rides to cool down the V11 sports that had vapor lock. 

[luhbo]

Nice story Where did they lay it on? Can't avoid Baywatch pictures coming at me..

Anyway, hot day now, I'm off for soaring.

[Chuck]

Nice story Where did they lay it on? Can't avoid Baywatch pictures coming at me..

Anyway, hot day now, I'm off for soaring.

In the V. This was the first year, and vapor lock was rampant with them.