Topic: Oil circulation problem?...getting hung up in neutral

[Bodi]

The pump has a bypass valve to limit oil pressure, with cold oil the pressure would get too high at high rpm otherwise. The valve dumps oil into the sump to limit pressure to about 60psi. This valve is pretty foolproof and rarely fails. If it stuck open you would have the oil light on at idle on a hot engine.
There's a bypass valve in the oil filter bolt as well, a clogged filter will have a high pressure drop across itself and the bolt valve lets oil pass through unfitered - dirty oil is better than no oil I guess.
Drained sump oil may look dirtier than tank oil. Dirt will settle in the sump and sit at the bottom, congealing on the relatively well-cooled bottom of the pan. Dirt collects at the bottom of the oil tank too. This isn't a symptom of any oil flow problems, either the oil light ON or a ruined engine would indicate oil flow problems.

[ron.cieri.313]

Hi everyone…riddle me this?...if the oil pump is pushing oil from the tank through the engine and other whereabouts as its supposed to, then it returns to the sump as its suppose to, but the round mesh filter is badly or totally blocked with gunk so that almost not oil is reaching the scavenger pump so can’t return to the tank but instead of running dry, oil pressure builds up forcing the relief valve to open and dumping the recently used oil back to the sump, and because the system is stymied with recently used oil, no new oil from the tank can be pushed into the system even though the pump is trying to do just that…in other words, simply put, what happens if the mesh filter is badly blocked?

…thanks!

I want to double check the condition of the tank oil to the sump oil when I return home but last time the tank oil looked honey colored and the sump oil looked like creek water…that’s why I didn’t change the oil sooner cuz when I checked the tank it looked good (I had changed the oil in December when I bought the bike)

[bryanj]

Scenarion dont work,
Oil is always sucked from the tank and if the relief opens is dumped to the engine sump, if the suction filter is blocked the sump fills up, tank empties and the red "Its Too Late" light comes on---assuming you dont blow all the oil in the case out of a loint, seal or breather and slide off on the resulting mess.

The return pump never totally empties the sump and so crud (techincal term) will sit in the bottom and turn anything black.

If youre oil light goes out and oil is returning to the tank stop worrying and ride it changing the oil and filter every 1,000 for a while or at least twice yearly if you dont do the miles

[Patrick]

If the screen gets blocked oil pressure will drop. I know this from experience. I had some old clutch plates I tried to reuse on one project shed a bunch of fibers and block a good deal of that screen. My oil gauge showed a serious drop in pressure. I though my oil pump was going out until I pulled the oil pan and saw all the fibers on the screen. If that screen gets totally blocked I expect oil circulation will stop.

Patrick

[Spanner 1]

So, with some further postings on the subject, I guess I was equally right and wrong !!
A blocked scavenge screen is a possible scenario ( per Patrick ) that's when I thought a bypass opened..(wrong)...in Ron's case(poster ) I don't now think that the scavenge screen is blocked as the slow delivery to the tank could not keep-up with the drain of the tank by the high-pressure side of the pump...i.e. dry tank.

[ron.cieri.313]

K...then I'm guess I'm back to making sure the mesh filter is clean anywho.

...and then checking to make sure the oil making through the clutch (per Patrick?) and replacing the clutch plates (per LLoyd)...and hope that solve my problem or else I may have 750 parts to sell.

[ron.cieri.313]

Okay...please feel free to say "I told you so"....drained the oil from the sump and then from the reserve tank into different clear plastic containers and they were they same color.

Also, removed the oil pan which was a real pain cuz these stupid but cool aftermarket exhaust were in the way and mesh filter was pretty clean.  There were, what I'm assuming to be, metal filings in the pan and embedded in the metal screen.

I clean the screen with a metal brush dipped in seafoam and it seemed to do the trick...is there an easier way to pop out this mesh screen for a more thorough cleaning although this does not appear to be the problem?

...and "yes", u told me so.

[Spanner 1]

ron, do you know how old your clutch cable is ?  Replaced mine, like a new transmission !
A #$%*ty clutch cable could have caused the whole mess..IMO.
As old as our bikes are, the clutch is still designed to dis-engage with a good clutch cable and proper adjustment to where statements like ' kick it into gear' would not apply...IMO.

[ron.cieri.313]

Cable looks good but...ya' neven know...I should try adjusting again to see if I can increase travel of the lever to which the bottom of the cable is attached to.

I'm cleaning the oil pan and will re-assemble, add new oil, check shifting for the yucks of it, then try re=adjustment (again) and then check for oil coming through the main shaft, discs...and then shift mechanism...and then...hmmm, well, it will be winter by then...so I'll see how I feel by spring...lol...l8r...ron

[ron.cieri.313]

Well, re-assembled after a thorough clean of the mesh screen and same problems exists. 

I also replaced the neutral switch...at least I have a functional neutral light for the first time.

I will check for all coming through the shaft but will also look under the rear left crankcase and the shift mechanism for any problems...any thoughts on the latter as in how to diagnosis?...thanks, ron.

[Spanner 1]

New clutch cable =$14.50 at MotionPro, not to nag ya but ya gotta' get one..IMO....if old, like mine was, no amount of adjust can compensate for years of stretching in the inner cable and compressing in the outer cable.....

[ron.cieri.313]

Ah, I did not think of it like that...will order one...never used MotionPro before but will check...sounds reasonable....thanks for "nagging"

I'm taking off the left rearcrankcase cover to examine the shift mechanism 2nite...any experience in what to look for?