RossKean
Well-known member
And now you know a whole lot more about your bike than when you started. Great that it is sorted out.
Fuel Pressure Question
- Thread starter Oakdave
- Start date
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12tinker
Well-known member
too much fun wiggling that valve cover on and off! Be glad you don't have a Gen 3 from what I read. If symptoms come back (heaven forbid) do a TPS diagnostic.
Still loving my '06 AE. Flush and bleed that clutch slave yet?
Still loving my '06 AE. Flush and bleed that clutch slave yet?
Oakdave
Well-known member
Earlier this year, I rebuilt the clutch master cylinder and also replaced the slave cylinder (because there is no rebuild kit available for the slave cylinder). The slave cylinder was leaking internally, which was causing a bad 'jerking/bogging' when engaging into first gear from neutral. The leak in the slave cylinder was resulting in the clutch beginning engaged sooner than the ecu was calculating, which is controlled by a sensor that is connected to the clutch MAASTER cylinder (instead of to the SLAVE cylinder, which would provide a more accurate reading of the throw out position at any time).
Dan S
Well-known member
Very good informative thread. Concerning fuel pressure. I say don't sweat the 47.0 psi specification. Even 20 might be enough to get you home. My problem seems to be a bad fuel pump or fuel pressure valve. A couple months ago after I replaced the coolant hoses going to the low idle wax valve it started having problems with cold start. Seemed to be running lean but it had no error codes and of course I checked and rechecked everything that I touched when doing the coolant hose replacement. finally I put installed a small tube into the air box and took a can of starting fluid with me on a trip to South Dakota. It ran fine on my 3600 mile ride thru MT, WY, SD and back but started doing the same problem when I got back to Oregon. Running fine at higher altitude seemed to play along with the idea that it was running lean. So as of today it looks like it's the fuel pump. Right now a test pressure gauge says it's making 18. I'm guessing 47 plus or minus a few is more than good enough given the fact that it will run albeit not very well at 20 psi.
Dan S
Well-known member
Well I'm pretty embarrassed. But let's just call it a series of unfortunate events. Albeit mostly self inflicted. But it's all fixed and running like it's supposed to. And note that I've edited the first post in this thread so a guy doesn't have to read the whole thing to find out the answer to his problem is probably not going to be found here.
The bottom line is that when I re-assembled the fuel pump like 2 years ago I did not get the o ring seal between the upper pump assembly and the lower or bottom mounting flange installed correctly so it's been leaking. It's a wonder it ran at all. The first photo below is how I found it yesterday when I pulled it apart except the o ring was cockeyed and kinked a little. Actually this photo shows how I reassembled it yesterday and of course it did not build much pressure. The second photo below shows how the o ring is installed in the lower mounting flange with the plastic snap ring holding in place. Then the end of the tube of the upper pump section pushes over the o ring when the upper section is inserted and snapped into the lower section.
So what was the Series of most unfortunate events? Right after I got this bike I decided to put Heli bars on it because I like a more upright riding position. Too bad they get in the way of just lifting the front of the tank to get at all the stuff under there. So 2 years ago I was working on my Rostra cruise linkage with the tank, about 3/4 full, propped up but not connected at the rear pivot point and it fell over and the fuel line broke loose at the barbed connection on the fuel pump assembly. Oh crap. And you can't buy any of the individual parts of this assembly. So I bought a used pump off flee bay, and removed the lower flange piece from the used flee bay pump and installed the lower pump section from my bike on the good part. Then I sold the pump section, sans the lower mounting flange, on flee bay for a total cost of about $40. Apparently I did not pay close enough attention to how it is supposed to go back together. It's a wonder it ran at all. And to think that I've put about 16 miles on it with it making only 20 psi fuel pressure. That's kind of a miracle.
The bottom line is that when I re-assembled the fuel pump like 2 years ago I did not get the o ring seal between the upper pump assembly and the lower or bottom mounting flange installed correctly so it's been leaking. It's a wonder it ran at all. The first photo below is how I found it yesterday when I pulled it apart except the o ring was cockeyed and kinked a little. Actually this photo shows how I reassembled it yesterday and of course it did not build much pressure. The second photo below shows how the o ring is installed in the lower mounting flange with the plastic snap ring holding in place. Then the end of the tube of the upper pump section pushes over the o ring when the upper section is inserted and snapped into the lower section.
So what was the Series of most unfortunate events? Right after I got this bike I decided to put Heli bars on it because I like a more upright riding position. Too bad they get in the way of just lifting the front of the tank to get at all the stuff under there. So 2 years ago I was working on my Rostra cruise linkage with the tank, about 3/4 full, propped up but not connected at the rear pivot point and it fell over and the fuel line broke loose at the barbed connection on the fuel pump assembly. Oh crap. And you can't buy any of the individual parts of this assembly. So I bought a used pump off flee bay, and removed the lower flange piece from the used flee bay pump and installed the lower pump section from my bike on the good part. Then I sold the pump section, sans the lower mounting flange, on flee bay for a total cost of about $40. Apparently I did not pay close enough attention to how it is supposed to go back together. It's a wonder it ran at all. And to think that I've put about 16 miles on it with it making only 20 psi fuel pressure. That's kind of a miracle.
Dan S
Well-known member
Anyway, thanks a ton to everyone for listening to my ordeal and providing comments and suggestions. You assistance in the this endeavor is greatly appreciated.
