Quota Non start when warmed up

[Wayne Orwig]

Not a direct answer to anything, just thoughts.

All of the cases of vapor lock take a lot more time to get hot, then the heat has to soak into the fuel line. As long as fuel is moving it should keep the lines cooled down enough to prevent vapor lock.

When you at first fire it up, the ECU automatically is in 'choke' mode. As in, it sprays a LOT more fuel in for the first minute or two, then starts to back off the 'choke'. So, if something has it too lean, it may fire and run even on the leaned out 'choke' mix, then as it leans out towards the normal setting, it is too lean. If that makes sense. It may be too lean, but run ok on the 'choke' program inside the ECU. GuzziDiag would show the injector pulse width, and the sensors. If a sensor is far enough out of whack, it may be too lean. Maybe the idle trim in the computer just went whacko. I have see that a few times, but it usually only impacts idle. I also wonder about the fuel regulator though. Not so easy to test. Does it have a fuel solenoid, and is it opening for sure. (fuel pour out under gravity if the hose is off?)

[Wayne Orwig]

Smithswede good suggestion. Tom, the fuel pump and filter are under the seat. Should I insulate them anyways? Anyways, the rain just started in earnest so I’ll get started checking in the morning and post results. Thanks

The only cases of vapor lock I have seen was on the V11, and after the bike was parked a few minutes, and VERY hot. The fuel would boil. Never saw it happen with the engine running. The pump is keeping fresh cool fuel in the lines so it would be hard to happen.

[GeorgiaGuzzi]

Thanks Wayne. When it gets warm enough for whatever to trigger it shuts down quick fast and in a hurry. Like I hit the kill switch. It doesn’t act like it’s leaning out before it cuts out. It pulls good then cuts out without so much as a by your leave! Quite annoying.

[Tom]

Yeah.  My V11 wouldn't start after sitting at a gas stop.  I'd have to wait an additional 10-15 minutes for it to cool down.  Your Quota sounds okay for fuel pump/filter.

[guzzisteve]

Are you using the cam sensor with the groove sliced into it that I seen in the other thread? May have something to do with it.

[Kiwi_Roy]

Okay, fuel pump is getting power after kill switch is switched on. It powers up for initial prime, then has power while turning over and when running.

When cool it started right up. Idled and runs well. After a trip up the driveway and on the way back down it got warmed up and promptly died. Fuel pump still has power when cranking over during non start. However, when I checked spark the left side spark plug has strong spark, arcing nicely on the crash bar. The right side spark however, has a very faint spark. No arcing, not bright, just a faint wee spark. I did purchase a very basic multimeter today. But I have never used one so further instructions for diagnosing this would be most welcome.

Cheers, Robert

This sounds like it might be something to do with the coil or perhaps the plug is tracking across the insulator instead of jumping the gap
One test you can do for us with your new meter on the Ohms scale is take a resistance reading from the plug cap to chassis, it should be the same on both sides somewhere in the range of 8,000 Ohms (8k)

[SmithSwede]

Two more. 

1) Since spark may be an issue, I’d try starting it in the dark and look to see if you have funny blue, but unwanted, arcing.   Pull on, jiggle, and re-route wires.  Spray WD-40 on stuff in case something is wet. 

2) Did you say DIRT DAUBERS???   I’ve had a ton of problems caused by dirt daubers.   Since this may be a fuel problem, and those devious little bastards were messing with a fuel related component, I would give that a hard look.  But again, if you can prevent the engine from dying when it warms a bit with some squirts of starter fluid, you will know this is likely fuel related.   If starter fluid makes no difference I’d go back to pondering sparks and wires. 

Go ahead and spray starting fluid on the dirt daubers though. 

Keep posting data.  We’ll keep giving you bad advice.   

[Wayne Orwig]

Thanks Wayne. When it gets warm enough for whatever to trigger it shuts down quick fast and in a hurry. Like I hit the kill switch. It doesn’t act like it’s leaning out before it cuts out. It pulls good then cuts out without so much as a by your leave! Quite annoying.

Makes sense. Likely not a slow leaning out.

Do you have a laptop to run GuzziDiag?

[RinkRat II]

         My money  ($.02)  is on the coil(s).
   
      Paul B

[Kiwi_Roy]

         My money  ($.02)  is on the coil(s).
   
      Paul B

Where was your money on July 28th?
Its very easy to jump on the band wagon now 

[Wayne Orwig]

Where was your money on July 28th?
Its very easy to jump on the band wagon now

 

[RinkRat II]

     

Where was your money on July 28th?

    I had to wait for my interest to accrue on my investment before springing the big buck wager. Plus it's so much fun reading all the other posts going down the "fuel" rabbit hole

       Paul B

[guzzisteve]

Where was your money on July 28th?
Its very easy to jump on the band wagon now 

Evidently the band wagon is still playing cause it still don't run. My money is on the new sensor w/a groove cut in it. Unless replaced since.

[GeorgiaGuzzi]

Yes, the “bobbing for Quota gremlins” is still going on. I can almost guarantee that we will know when we find it. Kinda like the you’ll find your lost item in the last place you look for it! Lol

Wayne, I do have an older windows 10 laptop.

Roy, my multimeter has readings up to 2000k. Is that 6,000 too few, or 1,992k plenty?

Steve, the new sensor is the one with a small cut in it. I’m not too worried about it because the old sensor had a bigger crease and the bike ran fine with it. But I’m not ruling it out. It’s in line after I check the fuel and coils.

Now Ima gonna go play with my recalcitrant Quota and report back.

Again, thanks for everyone’s input very much.

[GeorgiaGuzzi]

Okay, the resistance on the left hand coil (the one with lots of spark) is 7.8.
Resistance on right hand coil is 8.5.

Measured by positive feed attached at plug cap, negative feed to frame.

[RinkRat II]

      Thats good for the secondary side, check between the pos terminal and neg terminal on the coil for primary side ohms. should be less than 3to4 ohms, then check them both again after it's warmed up or stalls.

      Paul B

[GeorgiaGuzzi]

      Thats good for the secondary side, check between the pos terminal and neg terminal on the coil for primary side ohms. should be less than 3to4 ohms, then check them both again after it's warmed up or stalls.

      Paul B

So to check the positive and negative terminals I pull off the connector and check the actual posts the terminal plug into correct?

[RinkRat II]

    You are correct, should be just a couple of ohms.

     Paul B

[GeorgiaGuzzi]

    You are correct, should be just a couple of ohms.

     Paul B

Okay, with multimeter at lowest setting (200) the left side measures .4-.5 , the right side measures 1.1 . The measurements are with a cold engine.

[Kiwi_Roy]

Okay, the resistance on the left hand coil (the one with lots of spark) is 7.8.
Resistance on right hand coil is 8.5.

Measured by positive feed attached at plug cap, negative feed to frame.

 

I'm assuming thats 7,800 and 8,500 Ohms. The thing is the coils will be the same, the resistor caps will also be the same ~5,000 so the difference is in the high tension leads, that crappy carbon core wire i'm guessing.
This probably has nothing to do with your hard starting but I would change the leads out for copper core wire anyway.
Both sparks should be identical, perhaps you have a weak coil but whatever the reason don't be satisfied until you get even resistance and even sparks on both sides.
I doubt you can get any sensible reading on the primary of the coils, the resistance is too low to measure with a cheap meter (fine for the high resistance of the secondary)
You can probably measure the individual resistance of the secondary components ~5k for caps, ~3k for coils and the rest for leads which will be zero when you have replaced the carbon with copper core.

      Thats good for the secondary side, check between the pos terminal and neg terminal on the coil for primary side ohms. should be less than 3to4 ohms, then check them both again after it's warmed up or stalls.

      Paul B

As RR says if you get anything showing up when hot it would be a bad coil for sure.

[GeorgiaGuzzi]

When warmed up and doing it’s non start, both sides of the coil show 0.00 ohms. When the leads touch the connector prongs it shows 0.02, the 0.01, then 0.00. The multimeter does not show open loop, which would be a 1 on the left side of display.

Just saw your post Roy. Yes this is the cheapest multimeter. Me buying an expensive piece would be a waste on me currently.

[Kiwi_Roy]

When warmed up and doing it’s non start, both sides of the coil show 0.00 ohms. When the leads touch the connector prongs it shows 0.02, the 0.01, then 0.00. The multimeter does not show open loop, which would be a 1 on the left side of display.

Just saw your post Roy. Yes this is the cheapest multimeter. Me buying an expensive piece would be a waste on me currently.

It doesn't matter how cheap the meter is if it works, even a $5 meter can be reasonably accurate, the expensive meters usually have better leads and are safer to use on mains applications.
Hey, you are getting some readings now, we'll have you a sparky in no time lol

[RinkRat II]

   Even though the coils have heated up you should still have about the same readings as cold on the primary side. Me thinks some new coils are in your future.

      Paul B

[lucky phil]

How is the battery? Does it crank well after stalling and the no start? Just for info the Marelli ecu actually enrichens the fuel map for 3000 crankshaft revolutions after every start hot or cold so when you do a CO trim adjustment after a warm start you need to allow 3-4 minutes of running before you ascertain if the idle is better/worse. it's just general info so you know that it's not likely to be an issue with the engine going off the enrichment map thats causing the no restart. Doesnt mean its not fuel related though. Have you replaced the crank position sensor? They can be fickle things. You can buy cheap Chinese copies and I have used them successfully.

Ciao 

[GeorgiaGuzzi]

So it appears that these coils will work for my Quota. Am I correct in that thinking?

https://www.ebay.com/itm/402256010557

Also this fuel regulator looks the same.

https://www.ebay.com/itm/293693727959

Lemme search for cheap crank sensor.

I’m going to try downloading Guzzidiag too.

[Kiwi_Roy]

Yes and Yes
The small tube on the regulator doesn't have a hose on, its open to atmosphere
Actually I'd be surprised if your regulator is bad it comes after the filter which protects the injectors and regulator.

I suggest you fill the filter up with fuel shake it around then let the fuel run back out the inlet to flush anything loose out, the one on my EV was full of rust.

[Wayne Orwig]

It doesn't matter how cheap the meter is if it works, even a $5 meter can be reasonably accurate, the expensive meters usually have better leads and are safer to use on mains applications.
Hey, you are getting some readings now, we'll have you a sparky in no time lol

But....

I believe he said that the meter was on the 200 ohms scale. It may not have good range and good leads to measure the coil primarys that are near 1 ohm. (I'm not sure what the coils for an ECU are, but they are VERY low. Maybe under 1 ohm)

So maybe the meter isn't good enough in this case.

But even if one coil was failing when hot, the other cylinder would still fire and try to run. And the ECU uses a very short controlled dwell time. Not like the old points where the dwell time may be a lot and cause excess coil heat.

[SmithSwede]

I’m still waiting to hear if swapping coils moves the problem.  Or if starter fluid keeps it running. 

I don’t think it is the phase sensor.  Don’t think it would start and spark at all if that were bad.

[lucky phil]

I’m still waiting to hear if swapping coils moves the problem.  Or if starter fluid keeps it running. 

I don’t think it is the phase sensor.  Don’t think it would start and spark at all if that were bad.

True but sometimes they only give trouble when hot hence my interest in knowing how warmed up the engine is when it won't re start. These things are so cheap these days that if the original is 10 or 15 years old it's time to replace it anyway I think. They aren't like a remote baro or ambient temp sensor that if they go bad then the engine still runs ok and the system just reverts to a default value. This thing spends it's life bathed in 100-110 degree engine oil on a hot vibrating crankcase and when it fails you're on the side of the road or have an annoying intermittent problem.
It's what we used to term in the aviation industry as on a  "hard" time limit in my view. Once its done its klms replace it as a matter of routine maintenance.

Ciao 

[SmithSwede]

Good point.  I’ve learned this the hard way and now travel with a spare sensor in the saddle bag.