04 Sportster Le Di won't stay running.

Note: This site contains eBay affiliate links for which SeaDooForum.com may be compensated

PSBeachBum

New Member
2004 Sportster Le Di. I'd been t/s slow acceleration (at the time wear ring was new and carbon seal was newer). I though it was raves so I replaced them (engine is not bored over). I tested fuel pressure and it was low so I replaced fuel pump and filter with one from quantum. Fired up. Ran great. Did 20 miles and blew a fuel line. Replaced all the lines and it ran great for my test run but died on approach to the dock. I installed a gauge on fuel line and it reads the normal 27 psi on prime but winter make it to 107 running. I checked air compressor and it was 30 psi so I replaced sleeve, piston, rings, gasket, o-rings and inlet reed disk and am now getting less psi. I checked compressor head with my fingernail for any pieces missing causing inlet disk to leak.


Cylinder compression at spark plugs were and still are 90psi on both so I tested at air injector ports and got 130psi on both leading me towards leaking fuel/air rail components. I've replace just about all O-rings and I am still unable to get going.

Currently it primes 27psi and starts but will surge between 80psi and 100 psi and idle to it dying.

I'm at a loss on what to check next
 
Last edited:
Updates for future searches.
1. Found a crack in the air line going from air compressor to rave solenoid. Repaired. This was hard to find with #2.
2. OEM rave solenoid had broken nipple and ones I ordered from the far reaches of the internet haven't showed up so I used one off a ford eco boost. That failed and doesn't hold pressure from going to the RAVES in the first place. I tested with shop at to the broken OEM solenoid and verified that the lines no longer leak. Fingers crossed on receiving one from a DI ski partout
3. Quantum fuel pump cannot hit 105 psi. I did find potentially a missing o-ring on the adapter between pump and adapter. I've tired so many different o rings and no change in ability to hit 105 psi. Also the double lip gasket between adapter and fuel tank lid doesn't visually appear to be leaking.

I'm at the point I've got a ebay entire oem fuel rail coming (I threw away the OEM pump after I ran good for 20 or so miles on the water so I had to buy the entire assembly). I've also warranty claimed my fuel pump from quantum and if I get a replacement. I'll try that out regardless of it the oem assembly works.
 
Update: Replaced with all stock fuel pump setup. Works great. Still have to water test. So my entire issue generated from a leak in air supply to the rave. The rest is just poor diagnostic. The Quantum fuel pump also isn't performing correctly. I've replace it with their hfp-500 but I haven't installed yet as the stock replacement works.
 
Back
Top