99 GSX Limited Oil Line Bleed

[Retsamel]

I know there are many posts on how to bleed these 951 oil lines, but can't find anything on my specific situation, so here goes. I replaced oil tank, lines (in and out) and filter. Below is the bleed process I followed. Issue is that the short output line won't bleed. I'm getting some oil through it. but after running the engine 3-4 times for about a minute each, still has mostly air. The long line pushed the bubbles out on the first run. I even tried clamping off the long line to maybe force some more oil to the short one. No better. No visible air in the input line or long output.

Procedure so far:
-Let input line flow oil and then clamped off just before connecting to pump.
-Opened bleed screw for a few minutes which cleared remaining air in input line.
-Shot some oil in carbs
-Held pump wide open
-Started and ran for 1 min (3-4 times)

Any ideas on why one line only won't bleed. My logic based on symptoms is that the pump is pumping (long output line full) and air is not coming from inlet fitting (only one output line has air). Maybe I nicked the short output line at the pump nipple? Is there something internal to the pump itself that would explain this behavior?

 

[funsummerahead]

The only oil line you have to bleed is the one to the oil pump. There is a small bolt on it, 8 MM wrench or socket will work. Just loosen it - don't take it out- and, put a rag under it and let some oil come out with the air bubbles. When there aren't any more air bubbles it should be ok. Did you replace the 2 really small oil lines from the oil pump to the intakes?

 

[Retsamel]

Yes, as described, one of the small lines won’t clear of air.

 

[funsummerahead]

The oil lines connect to check valves on the intake that don't open until about 2 psi so they don't fill the engine with oil when not running. Sounds like that check valve is clogged or bad.

 

[Retsamel]

Thanks. Will check that although I can see small amount of oil and air moving through the line.

 

[funsummerahead]

With the oil pump primed and no air bubbles. I've seen when I start / run the engine and hold the oil pump wide open the oil will surge equally in both lines about 3/8" every 5 seconds or so, it doesn't just slowly flow. I would guess this is because the air is compressing up the 2 psi -or whatever it is- and then the oil goes through. It definitely sounds like that check valve.

 

[Retsamel]

Ok, I pulled the small lines off the pump. I can inject oil through the lines towards the check valve with a syringe. Using very slight pressure they flow freely.

When I crank the engine over and watch the pump outlet nipples with the hoses off, oil is coming out of both equally, but not squirting out. I see about a drop or two spill out of each nipple for every 10 or so engine revolutions and they alternate one side then the other. This is at wide open throttle.

Does that sound like about the right flow rate?

 

[Retsamel]

Update. As I said above, I squirted some oil through the small lines towards the intake and cleaned the pump nipples with a paper clip. I trimmed the ends of the hoses and put it all back together. Oil came through the lines and cleared the air. All looks to be working ok now unless anyone thinks the flow volume I described in the last entry is a problem. Assume it was some blockage as funsummerahead described. Thanks again.

 

[funsummerahead]

Here's some info to help but if you can check it AFTER the check valves that would be best. I'd hate to hear someone blew up a 951 for a bad check valve.