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Discussion Starter · #1 ·
Well, not good news today. I went to fire up my 312, the starter made a bit of a grind, then a clank. Tried it again and just a clank. I checked the battery and the positive terminal was very hot to the touch. Took the fairings off and had strong scent of gasoline. Looked around and checked the usual spots, not a trace of fuel. Got under the bike and discovered this:





I rode the bike yesterday and there were no problems whatsoever. It got pretty hot (blinking 240 on the dash) but once I was moving again, it cooled right down. It had a little bit of a hesitant start one time, but nothing bad. Put it away last night and didn't think anything of it. Just a normal ride. That was the second ride since I picked her up last Monday. Bike has 6592 miles, never had so much as a hiccup before.

Anyone have any thoughts?
 

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Discussion Starter · #3 ·
Nope, that's gasoline.
 

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Bugger Nick, not looking good man. Time to start stripping the bike man, get the tank out of the way, do not try to start the bike again until softer everything, you will probably find your starter and alternator flooded in fuel.
Just go steady now, no use rushing.
 

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Discussion Starter · #5 ·
I can't do much right now. All my tools, stands, and equipment are still in transit. I'm going to try and dig in further tomorrow. I'll keep y'all posted.

I'm so pissed off that I'm not even mad.
 

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Discussion Starter · #6 · (Edited)
Well, after doing some research on other people/bikes that have had the same thing happen, it sounds like the fuel pressure regulator diaphragm (and possibly the injectors) has failed which is causing fuel to continually flow through the system when there's pressure behind it. This caused fuel to fill the crankcase and cylinders and eventually flow out of the exhaust manifold. Fuel is only coming out of the left two exhaust ports, since they're the lowest when the bike is on it's side stand. I still don't have my rear stand as it's in transit (along with all my tools), so I'm stuck with working on the bike on it's side. I have fuel mixed with the oil and have to drain everything. I checked for coolant and that seems ok, so I don't think the head gasket is blown. The bike was running perfectly before I left it sitting for 24 hours, so I doubt anything internal has failed. I'm trying to find a suitable hose so I can drain the tank (which I just filled up at the end of my last ride) so I can remove it and the airbox.

I'll keep y'all posted.
 

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If it is the fuel pressure regulator diaphragm, what is the diaphragm made of rubber?
I am asking incase it is rubber, and it has deteriorated from use of 10% ethanol fuel?
 

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Discussion Starter · #8 ·
I'm guessing it's made of rubber. I too am assuming that it's the ethanol blend that cause the early failure. Considering the bike was sitting for 9 months, encountered sub-zero temperatures, and then reached over 240 degrees F here, it has been through a lot in the past year.
 

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Indy cars are race cars, one would expect specialised components for race cars, they also each have a team of technicians working on them, they rebuild for every race if they have to. Not sure your using a fair example?

For everyday users Ethanol fuel has caused quite a few headaches.
 

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I agree that is has, I'm just saying that manufacturers should know better... Look, the 2010 + F4s and now the F3s use plastic gas tanks. MV Agusta knows that the US uses ethanol-flavored fuels, and has for quite a while?

What on the god's green earth made them spec a plastic tank that gets eaten by said fuel? That tank could have been coated, a different formula of plastic could have been spec'd, or they could have gone to an aluminum tank if they wanted to save weight.

Insofar as rubber components that work with ethanol, those are off the shelf available standard bits.
 

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Well, after doing some research on other people/bikes that have had the same thing happen, it sounds like the fuel pressure regulator diaphragm (and possibly the injectors) has failed which is causing fuel to continually flow through the system when there's pressure behind it. This caused fuel to fill the crankcase and cylinders and eventually flow out of the exhaust manifold. Fuel is only coming out of the left two exhaust ports, since they're the lowest when the bike is on it's side stand. I still don't have my rear stand as it's in transit (along with all my tools), so I'm stuck with working on the bike on it's side. I have fuel mixed with the oil and have to drain everything. I checked for coolant and that seems ok, so I don't think the head gasket is blown. The bike was running perfectly before I left it sitting for 24 hours, so I doubt anything internal has failed. I'm trying to find a suitable hose so I can drain the tank (which I just filled up at the end of my last ride) so I can remove it and the airbox.

I'll keep y'all posted.
Just had a Honda Blackbird in my workshop with exactly the same problem.Fuel pressure regulator faulty causing excess fuel flooding the cylinders.Fitted new regulator,removed spark plugs,cranked it over to blow out excess fuel (to save hydraulic lock),changed oil and filter,and it was good to go.The rubber diaphragm in the regulator perishes over time therefore delivering full pump pressure to the injectors constantly.:jsm:
 

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Discussion Starter · #15 ·
Ok, so does anyone have a method for checking a FPR? I finally got it out after lots of careful cussing.

Also, anyone have a spare laying around? :D

Also changed the oil and filter. Switched to Mobile 1 full synthetic 20W-50 as per many recommendations from you lot.

Checked all my hoses and everything looks fine. Pulled the fuel pump assembly out. Everything is nice and firm, not eroded.
 

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Discussion Starter · #16 ·
Also, finally got the airbox off and it looks as though the air filter has never been removed since it left the factory. I've only put 1K miles on this thing since I bought it two years ago. Ugh.
 

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Normally,you would check the regulator with a vacuum pump to see if it holds vacuum.If it doesn't the diaphram is faulty.
 

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Discussion Starter · #18 ·
Don't have one of those handy. Maybe I'll take the regulator to a dealer and see if they can test it.
 

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I wouldn't expect you to own one.Most workshops have one.They vary in design but here is what they look like.

41ZR4KBYaUL__AA160_.jpg
 

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Discussion Starter · #20 ·
Took my regulator to a couple local motorcycle shops. They said they can only test it if it's installed on the bike. Useless.

I'll check some hardware stores.

Thanks!
 
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