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TheSkipper
05-17-2011, 08:36 AM
So for the past week week my buell would not start early in the morning. And its very hard to start any other time of the day.

Put a fuel pressure guage on it and it has nothing, but theNEW FUEL PUMP is running. So i take it about last thursday and the rubber gasket between the fuel pump and the houseing is cracked. Replaced that and it crank right up and ran great all weekend.d

Yesterday morning, get on it to go to work. Would no crank again. Put a gauge on it before i went to work. NO PRESSURE. But you can here the pump running.

So after i get off work yesterday, i tear it down again hoping the rubber gasket had broke again. NOPE. it was fine. So put a new on it anyway, check everything and put it bac together. Still wouldnt crank. Like it wasnt priming up. Well i unhook the line and kick the pump on and its pumping fuel. So i kick on and off several times and hook the line back up and crank it over and the fuel pressure shoots up too 55psi and it runs great!

So i take it on a 20 mile ride to charge the battery came home and parked it. I got up this morning and nothing again! So i grab a can of starting fluid and spray some in it and it cranks!

Rode it to work.. ran great. Any ideas of what the problem might be? It acts like it has air in the fuell system. Whenever it wont crank the fuel pump makes a different sound like theres no resistance, but when it was cranking like it was supposed to you could tell it was building pressure.

Weldangrind
05-17-2011, 11:15 AM
It sure sounds like air. Perhaps there is an air leak at a fuel hose that is upstream of the pump; under vacuum the pump will pull air past the leak, but at rest the hose doen't leak fuel. I'm guessing that the starting fluid allows the air to be purged more quickly, which subsequently makes fuel flow.

Is there a fuel pressure regulator in the fuel circuit? Maybe it's done.

2LZ
05-17-2011, 01:54 PM
That bike, I believe came with the 'new at the time' DDFI system on it.
Hopefully, you're not having a problem with the controller.
Does it have socks on the fuel pickup tube(s)? They get munged up....but as you say, it's pumping fuel from the pump.
Sounds more possible controller issue not opening the injector unit itself. Possibly not going into cold start mode, maybe?

TheSkipper
05-17-2011, 04:17 PM
Yes its the DDFI model, and the sock is at the end of the fuel pump itself, it has no "pick up tube"

But it has cranked up twice after this morning with no problems.

Is the controller the ECU? or does i of some sort of separate stand alone deal?

TheSkipper
05-17-2011, 04:21 PM
Is there a fuel pressure regulator in the fuel circuit? Maybe it's done.

Yes is attached to the fuel pump housing. I thought about that but would the pressure be abnormal if it has failed. 55psi is exactly what it calls for.

2LZ
05-17-2011, 06:38 PM
Yes its the DDFI model. Is the controller the ECU? or does i of some sort of separate stand alone deal?
Unfortunately, I don't know. With all the HD work I've done over the years, my experience with Buell has been slim to none. Mostly just a lot of reading, no real hands on. :?

TheSkipper
05-19-2011, 08:05 AM
Havent had anymore problems with it, hopefully it has cured itself.

2LZ
05-19-2011, 05:14 PM
Havent had anymore problems with it, hopefully it has cured itself.
Great to hear! :D
One thing to keep in mind.....with both injected bikes I've had experience with (mostly Vics and a couple of HD's), I've seen slightly dirty/loose battery terminals make mucho strange 'come and go' symptoms.
Always the first thing I check now.