Gas fouled plugs from sitting??? | Page 3 | GTAMotorcycle.com

Gas fouled plugs from sitting???

first thing I tried was removing the Juice box. my map is dyno'd and perfect.

Problem seems to be the battery and stale gas.

glen lent me a loaner battery. it cranked way more convincingly and had some really good close turn overs. some smoke out the rear too.

so i guess the culprate all along was the bloody battery..it failed with flying colours on the load tester. It even dropped 1/4 volt from my place to fs moto.

will confirm when i can get a jerry and some siphon action
 
Last I checked Cdn Tire had a Nice cheap Siphon pump on sale. Has a neat little Gas Pump handle too.

Works great.

Good luck.
 
Glad you are making progress. The last vid is def more positive. its almost firing on all 4.
 
did new gas and new battery. still not sounding good.

i will try a few more things tonight, failing that...im stumped.

its tough to get the fresh gas pumping i think, she's still sounding the same as before.
 
Try spraying a bit of quick start in the air box to get it going, might be the push that gets it started.

Sent from my SH-02E using Tapatalk 2
 
yea at this point, even though you have new gas in the tank, the fuel pump, the lines and injectors are full of the old stuff....at this point, you're gonna have to sit there and crank away, throttle wide open until she catches...

djbordie said:
did new gas and new battery. still not sounding good.

i will try a few more things tonight, failing that...im stumped.

its tough to get the fresh gas pumping i think, she's still sounding the same as before.
Click to expand...
 
What's more common in motorcycles? Return or returnless fuel systems? A thought crossed my mind that return type systems would have an advantage in dealing with stale gas. (Most volatile fractions still evaporate, but the most stale gas is purged from the lines faster)
 
return-less....i've never come across a motorcycle which have a return line....doesnt mean they dont exist but they are def rare
 
correct me if i am wrong but sometimes a battery shows 12.5 volts but justisnt putting out the amps. in which case it is a bad battery and still needs to be replaced. most only think of volts but amps need to be there too
 
if a lead acid battery cant put out the amps it drops its voltage under load like a rock due to the internal resistance. He got a new battery and now its cranking nice and sputtering. She'll start....just gotta get the old gas out and new stuff flowing.
 
OK so i got even closer now, i think it was the bad battery plus bad gas and ****ing around with it so much flooding it and such.

it starts up and shuts off now at least...extremely smokey. should i be worried about the smoke?

just giving it a brake then will try again.
 
Have u tried just firing it without any throttle?
When i had a carbed bike thats what i did to clear a flooded motor. I know your bike is not carbed but its worth a try

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djbordie said:
OK so i got even closer now, i think it was the bad battery plus bad gas and ****ing around with it so much flooding it and such.

it starts up and shuts off now at least...extremely smokey. should i be worried about the smoke?

just giving it a brake then will try again.
Click to expand...

Same when I got the RR finally started, I had to give throttle to keep it running and it smoked like crazy. After it warmed the smoke went away and it would run with no throttle input.
 
different concept. Carbs use venturi effect to draw fuel into the intake. They also have accelerator pumps (some) which squirt fuel in when you twist the throttle. So twisting the throttle usually ends up flooding the engine.

Fuel Injected bikes, the throttle body acts as nothing more than a gate for air. Injectors will quirt fuel downstream no matter what. So closed throttle body + injectors firing but engine not turning over = flooded engine. Open that throttle body wide and crank away at least will lean out the mixture and get fresh air in there....

RockerGuy said:
Have u tried just firing it without any throttle?
When i had a carbed bike thats what i did to clear a flooded motor. I know your bike is not carbed but its worth a try

Sent from my tablet using my paws
Click to expand...
 
Red_Liner740 said:
different concept. Carbs use venturi effect to draw fuel into the intake. They also have accelerator pumps (some) which squirt fuel in when you twist the throttle. So twisting the throttle usually ends up flooding the engine.

Fuel Injected bikes, the throttle body acts as nothing more than a gate for air. Injectors will quirt fuel downstream no matter what. So closed throttle body + injectors firing but engine not turning over = flooded engine. Open that throttle body wide and crank away at least will lean out the mixture and get fresh air in there....
Click to expand...

I'd keep that in mind

Sent from my Phone, dont judge the grammar
 
Red_Liner740 said:
different concept. Carbs use venturi effect to draw fuel into the intake. They also have accelerator pumps (some) which squirt fuel in when you twist the throttle. So twisting the throttle usually ends up flooding the engine..
Click to expand...

ok,, I am not up on newer bikes,, but it used to be only a Harley carb had an accelerator pump,, so if you didn't like a HD rider,, twist the grip a couple times, then watch him kick his guts out trying to start it... as it would be flooded..
so , you're saying it is common for a motorcycle to have an accelerator pump? all the carbs I have seen just have sliders ,, or a few have butterflies...

And the way i understand fuel injection,, it has a fuel rail.. that returns all the unused fuel back to the tank.. which works great for fuel that separates and looks like a B52 shooter.. cause it mixes it all back together in the tank.. where as a carb will allow that separated crap to burn off the volatile stuff.. and leave the other in the bowl.. and all over the plugs. Also,, a weak battery causes the computer to see bad sensor readings,, doesn't spin the engine fast enough ,, spark is weaker .. leading to fouled plugs

Red_Liner740 said:
Fuel Injected bikes, the throttle body acts as nothing more than a gate for air. Injectors will squirt fuel downstream no matter what. So closed throttle body + injectors firing but engine not turning over = flooded engine. Open that throttle body wide and crank away at least will lean out the mixture and get fresh air in there...
Click to expand...

I disagree with "no matter what"
my fuel injected harley has an air control from the twist grip.. and the computer knows the air flow when the starter is turning,, and the temperature,, and probably other sensors too.. and that determines the amount of fuel that is passed thru the injectors... so it doesn't flood
so, a closed throttle body, + engine turning over + sensor cold = cold start valve open + 3rd injector firing more fuel in = varoooom! engine starting without having to touch the throttle body if we have good fuel, and good battery voltage..
 
meester_jamie said:
And the way i understand fuel injection,, it has a fuel rail.. that returns all the unused fuel back to the tank.. which works great for fuel that separates and looks like a B52 shooter.. .
Click to expand...

I found the link that shows the separation
http://video.foxbusiness.com/v/2000862202001/
Buzzwords= phase separation
Bikes that have rubber and plain steel in the fuel system should notice.
I personally have noticed that E-10 gas results in poor fuel milage. pure-gas.org list non
alc. stations, good luck finding one.
mostly for what this gas does to aircooled engines, generators, lawnmowers, etc. The link explains why all "older car" makers will not honor their warantees.

then you should read
Not so. All vehicles sold in the US since 1980 have been required to
use ethanol compatible components. NREL labs have certified up to E25
safe for all vehicles and small engines used in the US.
http://liquidsunenergy.com/learning/multi.html
Or a direct link to the PDF:
http://liquidsunenergy.com/learning/ppt/Ethanol_Recommendations.pdf

Further reading beyond the sensationalism of the Fox News report shows
that phase-separation is an issue only when the ethanol
has become saturated in its ability to hold water in the fuel- as the
more expensive/gallon "Drygas" methanol additives did. These issues
come up when E10 is added to a tank already contaminated with water
(usually condensation from being kept close to empty and as weather gets
colder), or a contaminated gas supplier tank. Another issue is that
ethanol IS the octane booster, so it is 84 octane gas before the ethonol
is added; if phase separation occurs, the gas above the bottom
water-ethanol phase can damage your engine, even if you drain out the
water phase. This was not true for older tanks/pure gas combo-the water
settled to the bottom- your car would not start if water is sucked in,
but E10 acts as dry gas and can hold a quart of water (harmlessly burned
off) in a full tank. The take home message is keep tank topped off to
not allow condensation.
Other issues is that ethanol does solubilize off gums on the walls
of the gas tank, which could block fuel filters.
http://fuelschool.blogspot.com/2009/02/phase-separation-in-ethanol-blended.html
 
Think you're reading too much into my post, and i'm sure as hell not going to get into details on how exactly the whole injection system works. In the end you said it yourself, the injectors will fire, the ECU will moderate the pulse lenght but in the end the injectors WILL fire. Crank long enough with ZERO air coming in and even the reduced fuel being introduced will flood the bike.
Now, regarding the accelerator pumps, like i said, not all carbs will have it. Flatside carbs have them since they dont have a diaphragm that will draw the needle up to help richen the circuit when going from idle to part throttle. This helps with the transition and tries to eliminate the lean stumble. Just to add, the slide and diaphragm are joined and work together. The slide gradually opens via the change in pressure between the carburetor body and the diaphragm body. As the slide rises it raises the needle with it whose profile determines the part throttle fuel delivery.

This is how they got the carbs to have a smooth power delivery across the range and high performance.

I do agree with the Ethanol in the fuel probably being the culprit.
 
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Some flat slide carbs have pumps some don't (most four stroke ones do). All slide type carbs that I have seen have the jet needle attached to the slide whether vacuum or cable operated. On a slide type carb with the throttle held wide open the venturi effect is so slight that it won't draw fuel when trying to start. If you hold the throttle wide and kick or thumb the starter it will clear the excess fuel, even with an accelerator pump though it takes a bit longer because of the extra fuel. Unfortunately this doesn't work with vacuum operated slides (diaphragm). This may be the same on FI bikes but I am not sure about that. Nissan had to add an algorythm to the ECU on their early 90's Maxima V6 engines because they were prone to stalling after a cold start and were almost impossible to restart without removing and drying the plugs. Thus when it stalled it was possible to hold the pedal to the floor and hold it there until the engine started.
 
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