1999 VFR800 will not start

Background...bike parked in 2009 while I deployed overseas on and off for 4 years.
Battery is fresh and fully charged.
New NGK Iridium plugs.
Fuel pump, filter, and strainer replaced.
Tank emptied and refilled with new gas.

On key turn, I hear the fuel pump prime and fuel injection light goes out.
I loosened the fuel line at the fuel rail and verified, fuel is getting to that point...when I turned the key on, I got a nice spurt.

On cranking, it turns over strongly but will not catch unless I put starter fluid in the airbox. Propped the gas tank up, took the top of the airbox and air filter off and cranked while spurting starter fluid and it will run until I stop using the fluid...then it stops AS IF I am not getting fuel into the bike.

Replaced entire throttle body assembly with used assembly from a bike that was parted out after accident at approximately 3500 miles.

After replacement, I get exactly the same problem. It will fire and run on starter fluid but not without.

 

fuel injectors are likely clogged--they will need to be taken off and cleaned, either manual flush of high strength solvent or ultrasonic cleaner

 

Both old fuel injectors and new?

I replaced the fuel rail with a fuel rail from a bike that only had 3500 miles on it...I doubt they would be clogged at that point...it would also be exact same symptoms as my old fuel rail which I thought might be clogged so I replaced...so how do I test if the fuel injectors are functioning...simply?

 

Isolate each injector from the rail, and have a 12volt battery handy, spray some carburetor cleaner in an touch the two terminals with the wires you rigged to your source battery. You can also reverse the polarity to shock the pintels free.

 

Ok, that should be a beggining fix if the injectors are the problem but what is the likelihood of all 4 injectors not firing? Also, you say isolate...do you mean I need to remove all of them from the fuel rail or can I simply disconnect the connector?

 

Individually, have an extra bike battery or other 12 volt source and have you jumper wires ready and touch the ends. Juice them up with carb cleaner before you do this, you can reverse the polarity by switching wires on terminals. Used to do this on bmw injectors and fool pumps, good luck

 

i use a syringe to force Berryman's carb cleaner thru injectors while using 5 to 9 volts to energize the terminals.

 

Ok, happy to try this when I get home this weekend...now as devil's advocate...what if I verify function of injectors and still same problem? What is next?

 

One problem at a time, dollars to donuts you got crude in them pintels. Love my turkey baster and my ear irrigating ball to be sucking or introducing various fluids to stuff.eace: love 9volt batteries too

 

Hate pulling that throttle body assembly off

 

You can determine or prove to yourself that the injectors are clogged by trying to squirt fluid thru them with a voltage applied to the terminals--if nothing gets thru then they are clogged.

Everything else is working since it fires and runs on starter fluid, and you have replaced or cleaned everything down to the injectors. But the entire fuel system needs to be verified clean and functional from tank to injectors and everything in between.

 

Doesn't it seem a bit unlikely that all injectors would be blocked simultaneously on two sets of fuel rails? I would have thought that was more symptomatic of an electrical malady. All the injectors share a common black/white wire, have you looked into dirt/corrosion in the big grey 10p connector?

 

He said he swapped the rails not the injectors and to me the rails are a separate item from the injectors; if the bike sat up for a time then all the injector pintles could be clogged with dried up fuel residue. But if the injectors were swapped with the rails, then maybe it is electrical-- but still need to verify that the injectors are open and working on the bench or squirting into a bucket on the bike.

 

He said he swapped the rails not the injectors and to me the rails are a separate item from the injectors; if the bike sat up for a time then all the injector pintles could be clogged with dried up fuel residue. But if the injectors were swapped with the rails, then maybe it is electrical (fuse?)-- but still need to verify that the injectors are open and working on the bench or squirting into a bucket on the bike.

i dedicate this post to Doug Polen and his ducati 888 haybale encounter at CMS, which i witnessed in person.

View attachment 39981

 

The injector test that the other posters are recommending is a great diagnostic test. Triggering an injector with a 9-volt battery will immediately tell you whether it is seized up with fuel goo/residue. The moment you complete the circuit between the injector and 9-volt batter a healthy injector will make a nice "ting!" sound (and if you're holding the injector in your fingers you can actually feel the injector jump slightly as pintle moves).

If you complete the circuit with the 9-volt battery and don't get that "ting!" sound it's time to spray some carb cleaner.

I was working with some ZX6R injectors recently and I took some pictures:



Closeup shots of the output end of the ZX6R injectors:

 

My apologies, I meant the entire throttle body assembly including injectors, not just the rails.

 

Did not get to it this weekend, spent the weekend taking care of sick baby...hopefully this coming weekend.

 

At the risk of stepping in it....

I have had no reason to pull the injectors of of my bike. But I have had many out of cars. The most recent set went back in a couple of weeks ago.

I am only guessing that there are pretty direct crossovers for design and function between car and bike injectors.
If you want to learn about fuel injectors for gasoline, the spot I'd start for good information is here: http://witchhunter.com/

Re-assembling a Subaru 2.5L, (Head gaskets, valve job, etc) with mega-mile injectors seemed wrong, so I numbered them, and sent them off to WitchHunter.

The short version of what gets done
1. Visual examination.
2. Coil Resistance Test.
3. Leak Test.
4. Spray Pattern Test.
5. Flow Test.
6. Pulsed Flow Test.

Those are BEFORE disassembly and cleaning. Then, all tests are performed again, with new internal screens and all new O-rings.
Results are charted, with before/after stats for individual injectors.

I got back a small baggie with all of the old parts inside. What caught my eye was how corroded the super-fine screens were.
We can probably attribute that mess to the ethanol in most pump gas. This motor had not run in about 26 - 28 months. Two of the injectors tested initially pretty OK. One was flowing between 50 and 60%. One was 100% stopped up, no fuel passing at all.

Can an injector be completely hydraulically non-functional, and be recoverable? Yep.

I dunno if this guy (Blake, I think) does motorcycle injectors or not. If not, maybe he could suggest someone he'd trust that does.

Every time I have sent off injectors to be cleaned and tested, I have been happy with the results. Self-cleaning might be OK, but having the equipment and knowledge to do it right just has to give better results.

 

Those tiny holes in the zx6 injectors look like the ones used in Nissans--just takes a tiny piece of crud to jam em up. Diesel injectors can get away with tiny orifice injectors, but their fuel pressure is measured in the hundreds of psi; that design doesn't seem practical with ethanol...

Never put used parts on a bike without testing and verifying that they are good and functional first--no need to trade one problem for another especially when you have it torn down so far to get in there...

Wouldn't expect the second set to be clogged also, but where did they come from, how long did they sit, etc...