Recently had the oil pump gear fail which sent a tooth down into the pump and locked it up. Pulled over as soon as the light turn on and took it home on the truck. Got everything replaced but now the oil light stays on long after turning the engine off. Sometimes it will stay off a few minutes or it will stay off for a few days. I replaced the switch and it is doing the exact same thing. I even "borrowed" the switch and check ball from my friends Buell x1 which I know works and nothing changed. I then attached a pressure gauge in place of the switch and it shows that pressure will go up to 12.5 while cranking and drop down to about 6 after sitting for a while. Wondering if the new 07+ pump is changing anything from the 98+ pump that I replaced. Hammer performance says they are interchangeable and they both use the exact same switch and check valve part numbers so I'm not too sure that's the problem. I'm pretty sure the pressure is stopping at the check valve and not the lifters since when I remove the check ball it no longer holds pressure. I've read some forums saying that their bike is just like that and it's fine, but my oil pump incidence has me a little too nervous to do that. What if the pump breaks again and it takes several minutes before that light turns on? It always used to turn on as soon as I turned the engine off. This problem has had me stumped for almost a month now. Also, does anyone have a pressure gauge installed while keeping the factory light? The brass elbow I got can't screw into where the switch is because the motor mount is in the way, I would like to see someone else's setup.

 

try researching the sportsterpedia
http://sportsterpedia.com/doku.php

 

Can't seem to find anything about this on there. Only problems they mention is if the light does not turn on. Neither the electrical or oil section mention this issue

 

the oil light circuit is simple as sin. key off, light off, key on engine not running, light on, engine running, light off.
you have a power source that flows from the battery when the ignition switch is supplying power, the power flows to the oil indicator light, trough it to the oil switch which grounds the circuit and the light comes on. when you start the engine, pressure opens the NC switch which breaks the circuit ground and the light goes off.
if you have a wiring issue, and it is grounding to the frame somewhere, the light will come on.
mechanically, when you stop the engine, any oil pressure trapped in the system will bleed off. the spring on the check allows for a set pressure to make sure the light will function, has nothing to do with engine oil pressure, that is controlled by the restriction of the oil passage system and to an extent temperature. i assume your oil routing of the lines are correct. the clearances in the pump will allow oil pressure to drop when not running either back flow or wet sump pathways.
your description above seems contradictory somewhat or i am reading it wrong.

 

Sounds like a chunk went past the pump. Owners manual will have a oil feed map. Im guessing a chunk is clogging the way and could cause catastrophic failure. On a Shovelhead I would remove the front rockerarm button to check for oil flow, but not sure where to check for oil flow on the Sportster. I would not ride, only start to test until I found the problem. I believe many totally disassemble completely after shrapnel is introduced to the inside of a motor.

 

was it the drive gear or the driven gear?
a long time ago on a brake system, i had an internal hose failure which created a flap inside the hose and when the brakes were applied, it held pressure for a good while, was a bear to find but i removed the line and ran a wire through it and found the cause.
on the xlforum, you will find that an oil gauge can be added, just do not remember the member that did it.
if you go there, get in touch with hippysmack, he is one of the authors of the sportsterpedia and knows this system well.

 

I don't believe wiring is the issue, I can take the plug off and ground it out and the light will turn on every time. My problem is the pressure isn't bleeding off. I put a pressure gauge in place of the switch and it shows that about 6 psi is being held on the pump side of the check valve when the engine isn't running. That pressure won't bleed off for days. Not sure if the oil is supposed to bleed off through the pump or if the check valve is supposed to open at a lower pressure letting only a couple pounds stay. Also, if I crank it with the check ball removed, no pressure is built and the light never turns off so all that pressure is being held on the pump side of that valve.

 

A tooth came off the drive gear which found its way down into the pump. The pump locked up which destroyed the rest of the drive gear. Not too sure how that could have damaged the hose since no oil was flowing through it after the first tooth entered. They are original 02' hoses so I guess deterioration could be a possibility. I did get a gauge installed though, all it took was some 1/8" npt fittings and some hose, everything from home depot.

 

I don't think any chunks got through after the first one got in because that chunk was still in the pump when I took it apart. If any did make it through I don't believe it would get past the filter. There was shavings in the filter, but no chunks. I completely took apart the cam chest and both the rocker boxed. Everything was thoroughly cleaned. Wouldn't want to do all that work just for a chunk to destroy the $200 pump again. Never found any glitter or chunks on the filtered side of the oil passages though so I think I'm good as far as all that. Didn't want to split the cases anyways so I'm glad

 

oil from the bag>inlet of feed gerotor section>through oil hose>right case filter casting>through filter outer ring>through media>past check>to engine.
past the check, the oil is open to the world with soooo many bleeds. i assume the check is in proper orientation.
that leaves gerotor/hose on the back side and that is where the pressure switch is located. since the pump is new, clearances will be tight but still not enough to stop the oil from backing up through the gerotor or the shaft to the cam case (wet sump). if you turn the engine off with the bar switch and the light comes on, that tells you the switch is working. when you start the engine and the light goes off, again the switch is working. so yes, it would be possible for oil pressure to reside, but if the light stays out with engine off, then there is an issue and 6 psi is about the tripping point for low pressure