Oil Leak - Suspect counter shaft seal

[Chad76]

I need some techical advice from you gurus.

I have a yzf 450 04 model.

Went for a ride on the weekend and 10 min into it I had picked up long stringy tree bark that had wrapped itself around to the width of the front sproket to the point it was compressed solid. It had done the same to the rear sproket. Have never seen anything like it. Took me 45min to rip it all out before continuing the ride. Mind you I still have the front plastic gaurd on for the front sproket which would not have helped.

Got going again and continued for about 32k's. Bike was not running 100%. The power was lacking it's usual bark. So decide to pull over after 32k's and change the spark plug. We were at altitude and riding in the snow so this could have been part of the reason. Thin air etc. After taking about 30min to change the spark plug (it needed replacing by the looks of it) I tried to fire her up. Almost fired up 1st and second kick. 3 - 20 kicks later nothing.

Checked bike over and soon realised the bike had been leaking oil from what I could gather from the front sprocket area. There was so much mud on the bike it was hard to be certain but I am 99% sure it is from this area.

I checked the oil dip stick and no oil reading! @^!%@ Mind you the bike was stationary for 30 mins and to get a reading you are meant to have the engine running for 3 min.

Was highly concerned about how much oil I had lost so did not take the risk and got my mate to tow me back.

Cut a long story short....I have cleaned up the bike....dumped the oil and could not be happier to see oil come out. Checked the oil filter and it was as if it was brand new. No fragments in it. I measured how much oil I had drained out of the cold bike (did not pre warm it up as usual before dumping oil). I had 750ml left. The bike takes 1200ml total. So I had lost 450ml.

Questions:

With just over half the amount of reccommended oil in the bike would I have done any damage internally?

Do I have to split the engine to change the counter shaft seal?

My main concern is any internal damage with the amount of oil I had left....or was that still enough, and I am concerned about nothing?

I will determine the exact point of leak once I get a chance to fill her back up with oil and take for a quick spin to anaylise exactly where the leak is, now that I can see with all the mud removed.

Appreciate any advice.

[William1]

Your engine is probably fine.

Remove the sprocket, pull the seal, put a new seal on. That simple.

[grayracer513]

Questions:

With just over half the amount of reccommended oil in the bike would I have done any damage internally?

No

Do I have to split the engine to change the counter shaft seal?

No

My main concern is any internal damage with the amount of oil I had left....or was that still enough, and I am concerned about nothing?

Most likely

[matt4x4]

Chad - do yourself a favor when you replace the seal, oring and collar (yes, best to replace all those together), check the countershaft for play, ANY side to side play means you could be blowing that bearing at any time - in which case, it's better (more cost effective) to replace it right away instead of waiting until it turns into bits and pieces that will damage even more stuff inside.

And yes - if you have to replace it you will have to split the cases.

[grayracer513]

In a case where the seal leaks as a result of wear over the long term, I would agree that the collar would most likely need replacement because it would probably have a significant groove worn in it, and for the few cents the O-ring costs, it would be silly not to replace it. With the age of the bike, it merits close inspection, anyway, even though it may never have leaked were it not for the damage from the debris.

On the bearing, don't confuse axial play (end play), where the shaft slides in and out in the bearing with the sprocket removed, with an excess wear situation. Such play is completely normal, as it is the bearing under the sprocket that controls that play, and with the nut and sprocket removed from the shaft, it can be expected to slip in and out a considerable amount. Check the bearing condition with the sprocket bolted on.

[Chad76]

Thanks for the heads up. I'm feeling a little better that I may be over concerned about any internal damage.

Cheers.

[Chad76]

Finally had a chance to look at the bike...I have confirmed that it is the counter shaft seal leaking. I have pulled the drive sprocket off and the steel cover that sits behind that with two bolts. I can see the seal....but what are the best steps in removing this seal without damaging anything? Do I have to remove the collar first? I assume the collar is the thing that sits between the seal and the saft? How do I remove this without damaging this. Seal or colar first and what are the steps and best method? Thanks for any advice.

[grayracer513]

Place the trans in any gear. Put a center punch or other punch into the center hole of the output shaft and tap it inward. This will break the bond of adhesion that has formed between the O-ring on the shaft and the collar. Then grab the collar with a pair of pliers, twist and pull it free. Then, you will have plenty of room to hook the seal out, and inspect the collar for damage.

[Chad76]

Thanks gray....I ended up using multi grips to pull the collar out. I logged off before I got to read your response. That is great advice...I would not have thought of that. Makes sense. I looked throughout my manual and could not find a breakdown diagram displaying the individual parts around the counter shaft so it was sort of guess work. But got the job done without any damage. My collar has a difinate groove around the entire collar. I imagine this is why it was leaking or a combination of the seal included. So I will be replacing both. I noticed a spring like O ring embedded behind the seal. Should I replace this as well?...or does this item come with the new seal? Thanks for your help gray. Any tips in the re-installation of these parts? Cheers. I dont want to be stuffing around in this area again for some time ;-)

[Chad76]

PS...i checked any side movement of the shaft and there was none at all. The bearing is fine thank goodness!

[grayracer513]

I noticed a spring like O ring embedded behind the seal. Should I replace this as well?...or does this item come with the new seal? ;-)

The lip spring comes with the seal.

[matt4x4]

However, there is an O-Ring on the shaft behind the collar and before the bearing - you definitely want to replace that too.

[Chad76]

However, there is an O-Ring on the shaft behind the collar and before the bearing - you definitely want to replace that too.

Yeah b@gger me....finally got all the bits after having to wait two days and only discovered the O-Ring on the shaft that you are talking about now. I thought the O ring that everyone was talking about was the one within the seal. Oh well...back to the shop. Hopefully they have these in stock otherwise I will have to wait another 2 days.

Another question which way does the collar go in? Does the smooth edge face out towards the drive sprocket with the notched edge's facing towards the bearing? I cant seem to find a diagram anywhere. Im sure once I start putting it all back together it will make sense. I debated about bothering with the O-Ring but it makes sense to replace that now as well. Thanks for the heads up.

[grayracer513]

The notched side goes in. And while we're on the subject, you'll notice one side of the sprocket has a groove cut in its face that would look pretty cool on the outside. The sprocket isn't offset either way, so there's no reason not to put the lighter looking side out, right?

WRONG. The groove is there for clearance for the steel dust cover, which overhangs the end of the collar. If you don't install the sprocket flat side out, it will drag on the dust shield, and bind up the shaft.

[Chad76]

Thanks for the advice...last thing I need is to b@gger it more.

[Chad76]

How far do I bed the seal in? I have placed the collar on first and placed the seal over it. Used a 32mm socket and tapped it in slowly. How far do I tap it in? Until it stops or only flush with the case lip? I have already gone 3mm past the case lip. Is this too deep now??

[matt4x4]

Flush is correct, but if you leave it as is it'll be fine - don't risk damaging it by trying to pull it out to flush again.

[grayracer513]

Look at the old collar. How much room was there between the notches and the wear groove? That will tell you if the seal is OK at the depth you have it. Flush is proper, but deeper is OK if the seal is square with the bore, and rides on the collar.