03 YZ450F Oil Not Getting Up and Into the Frame Tank

Change the oil as alwayes in the past. Filled case with a quart, started and ckecked the dip stick, little low added more and started again up to above the mark and all was good. Went riding Sunday and all was fine for a few sessions and felt some thing was not right, checked the dip stick and nothing showing. Had no oil to add so stopped riding. Here is the problem. got home and aded oil what I thought would be the proper add. Started and still nothing on the stick, ran the motor the same amount that I have since I bought the bike to get a reading and still nothing. Shop sugested I flush out all the lines. Did that to all lines, cleand the frame screen. Refilled still nothing, Also removed the oil pump and checked operation, all good. Back together, refill still nothing going up to the frame tank. Tonight I check behind the stator for plugged passages all good. But noticed small yellow wax like particles behing the stator. Blew air into the shifter side oil line and decided to spray some carb cleaner under the oil pick up and got a lot more of the waxey goo on 4 towels before it ran clean. Alway used Yamahalube 20w50 mineral oil, changed every 3 rides or 1 race. Looking for thought on why no oil up to the tank. Going to reassemble after I here some ideas on the waxey substanance and a possible caues for the oiling issue.

Thanks in advance

Possible causes are a sheared drive pin for the rotor of the return oil pump (the one that sits in the crankcase) or a clogged pick up screen (blow air or force oil back through the larger opening behind the return pump rotors).

I have no idea on the "yellow wax". It's not a milky, foamy slime, is it?

Did the scren last night. Oil is not milkey, been there with a bad water pump seal. Just finished putting it back together, put in a quart started and ran still nothing on the stick add 4 additional oz of oil for a total of 36 oz of oil and restarted still nothing, but have better oil flow up to the head. Going back into the oil pump and some more back flushing. Did find two little pieces of the tape on the stator comming loose and removed them. Still perplexed, going to take the clutch side apart again. will advise of the findings.

Remove the return oil hose from the left side of the engine and verify that it pumps oil from the attachment point. Then with the dip stick removed from the frame, check for free flow through the hose and up into the tank.

Will do that next to the lines once I put it back together. Oil pump out both pins good and no clogged passese in the oil pump.

Think we found the problem, the rubber snubbers in the Barnett Clutch basket are comming apart. There were little rubber part all packed up inside the back of the basket up against the gear, cleaned most of them out but now the problem of how to get the gear off of the basket. Red locktight and bad allen bolts, any shgestions, Heat did not work!

How much heat?

You could very carefully drill the heads off.

How much heat1 Lots, on the head to get it red hot on the head on the thread sticking thru, you have to melt the rubber cushions to get it hot enough to get the red loctite to let go. Then you have a mess of melted rubber to remove, but all the oil makes that kind of easy. Emailed Barnett and you can get new rugger cushions and bolts from Barnett, they said hat the cushions will deteriate over time. Word to the wise is if you have a Barnett clutch baskes and clutch pack, keep an I on it take the clutch basket out and look at the back plate for the cushions comming apart, it will also show up in the filter. This all happened in about a months time. I am in no way knocking Barnett it has held up and worked geart for 4 years and lasted way longer than the stock basket and the stainless steel liners keep it from damaging the basket. I will buy another one when thim time comes for the other 4 Yamaha YZF I own.

Forgot, do NOT drill or grind off the heads in this case if you do so you will NOT have enought thread showing to get a grip on to heat and remove them. If you do you will need to buy a new basket. Find a good guy like I did and you will be spending $25-$30 vs $250+ for a new basket.

How much heat1 Lots, on the head to get it red hot on the head on the thread sticking thru, you have to melt the rubber cushions to get it hot enough to get the red loctite to let go.
That's what I was going to say. Map or propane torches are too cold, and scatter the heat too much, although if you use them from the back side only, they can sometimes turn the trick for you.

An oxy/acetylene torch, OTOH, can concentrate the heat on a near pinpoint, and heat steel fast enough to make use of the fact that there is always a thermal barrier between two separate parts, and that aluminum carries heat away very quickly. That means if the bolt is spot heated red fast enough, the aluminum basket won't rise to a temperature high enough to damage it.

The heat does not only break down the Loc-Tite. A tightened bolt is under tension. Heating the bolt to the point where it turns red softens it enough to let the clamping tension stretch the bolt some, loosening it a bit. The important thing is to heat the bolt as fast as possible and to focus the heat as much as possible only on the bolt.

This is a trick best left to someone who is more experienced with a torch, especially around aluminum, etc. But it looks a lot scarier than it actually is, and it's saved my butt many times over the years.

After going thru and removing the oil pump to clean all oil lines and getting more clutch chusion debris out of the cases, all was put back together tonight I put a clear hose on the suppy line to the frame tank so i could see if and how much oil was going up to the tank. The oil going up to the tank was weak at best. I verified the correct amount of oil was in the motor. Any thoughts, new oil pump? When the oil pump was out I flushed all oil lines and passages on the clutch side and the pick up screen.

One thing to remember is that the return pump has something like twice the volume of the feed pump. What this means is that the return will always outrun the feed by design. It should flow like gang buster at first, but after the excess oil that settles in the sump is cleared, the oil flow that you would see in the return line should normally be sporadic and intermittent, with lots of bubbles in the line. A healthy return pump should put most of an entire quart of oil into the frame in less than a minute.

Flow is the same even after a minute not even close to your description. Going to tait it apart after this weekends race. Going to at the pick up screen a littlie more intence and try to get upder it with a brush before I split the cases. Also going to chect the oil pump tolerances. Should be intresting old guy +50 on a CR 125 two stroke gota race.

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