Fuel pump dying?
First time caller, long time listener, love the show...searched and didn't seem anything similar. Most problems are won't start at all or idles roughly.
I have an '04 XB12 that hasn't run in 3-4 years. Looking for a good Buell shop where I can ship it and have them wrench until it's fixed. I've tried a couple of H-D mechanics who didn't know Buell--they were about as useful as a football bat. Alternately, if one of you has an "aha" moment, I'll take it!
What it does:
- Primes
- Injector checks click as they should
- Coil checks appear good
- Starts after ~2 seconds on the starter, one throttle blip, and then dies in ~1 second
Things that have been done:
- Replaced intake seals, mechanic said they looked fine
- Replaced plugs
- Changed all fluids (gas is good)
- TPS reset
- Checked AFV, was high but that's from the last time it hit closed loop (years ago), and before switching out the seals. Reset AFV to 100.
I love wrenching, but have minimal time to do it (family & job > wrenching). I do have ECMspy and am comfortable with the app.
Fuel pump dying?
Jack-O-Lantern
2006 Buell XBRS LightningBolt
http://www.buellxb.com/forum/album.php?albumid=129
I'd clean or replace the plugs first and then check fuel pressure if it still happens.
I had similar problems with hard starting on a cold engine. Turns out it was a hole in the supply flex hose within the fuel pump assembly.
https://www.buellxb.com/forum/showth...-problem/page2
You may be able to get by just buying a replacement hose. But it's a lot of work to get that assembly out, so at least also replace the two filters and maybe also the regulator.
Thats a good point Endopotential^^^^. A compromised fuel line on even a good fuel pump could cause exactly that symptom. It would be a good idea to clean the tank and fuel pump sock after 4 years anyway.
You didn't mention it but I hope you already drained the tank and put in fresh fuel!
Pulling the fuel pump is a 10 minute job
Support the rear of the bike using a strap thrown over a A-frame ladder or garage beam to the pillion peg mounts.
Remove the lower shock bolt and let the rear wheel hang down.
Drain the tank with the 1/8"MPT plug and unplug the connector.
Remove the 4 flange bolts (I protect the swingarm with some blue painters tape).
You can either make a puller, or carefully pry it out with a flat edge. A little 1/4 twist and the whole assembly is in your hand.
I would replace the easy to find Viton O-rings, but you can re-install them carefully with lube. If they are too swollen to re-install, let them dry out and they should shrink back to original size.
your symptoms are clearly a dying pump. failure to start and idle plus high AFV clear indicators.
rebuild the entire pump. piece-mealing with a filter here...a seal there typically yields poor results. i'll caution you it is NOT cheap and it is NOT a 10 minute job to remove. but the time and money spent are well worth it as reliability, performance, MPG and cooler running temps are the result.
PM me if you need the kit or a rebuilt or new pump.
Good info ^^ above, I would spray fuel in the TB see if it runs. if it does. rip out the pump like they say above ^^^^
Dang, Cooter. Your "10 minute job" was more like a 3 hour ordeal for me. Mostly because I didn't realize you could drop the swingarm far enough without removing the rear wheel. Which meant fashioning an axle removal socket from a 7/8" coupler nut, which was more like 15/16" to start with.
Hopefully I won't have to pull out another fuel pump anywhere in the near future. But at least now I know how
It usually is a 3 hour ordeal, the first time. You'll probably knock it out in 30 minutes if you had to do it again (hopefully not!).
Last edited by 34nineteen; 07-01-2019 at 03:44 PM.