Topic: Oil leak due to overfilling oil?

[Justin_NJ]

I changed my oil/oil filter for the first time since I got my bike using Honda GN4 10W-30 SJ.  Then I went for my first long ride.  When I got back, I had a line of oil coming down from where the shift lever attaches to the engine case.

Could overfilling the oil have caused this?  I think I might have filled the oil a little over the top line mark on the dipstick.

If that didn't do it, then I'm guessing the shifter seal needs to be replaced.  Does anyone know the part # for the shifter seal for a 1978 CB550K?  I couldn't find it on Partsfish. 

Thanks,
Justin

[Einyodeler]

You`ll need to take off the sprocket cover & see if it really is coming from the shifter seal as it could be coming from the oil pump O-ring or sprocket shaft.

Shifter seal # 91202 - 216 - 000   
 ( 14 x 24 x 5 )

Sprocket shaft seal # 91205 - 283 - 010
 ( 33 x 57 x 7 )

[Chris Liston]

After I had put that same honda oil in my 550 last year the shifter shaft seal started leaking too.  Its an easy fix if that is the problem, took me about 5 minutes once I figured out an effective way of removing the old seal (2 hours).  Where is the oil on the dip stick?  Is it within spec?  I had changed the oil and not filter and overfilled it alittle, used a fluid pump to remove excess. 

[Tim.]

After I had put that same honda oil in my 550 last year the shifter shaft seal started leaking too.  Its an easy fix if that is the problem, took me about 5 minutes once I figured out an effective way of removing the old seal (2 hours).  Where is the oil on the dip stick?  Is it within spec?  I had changed the oil and not filter and overfilled it alittle, used a fluid pump to remove excess. 

Share the wisdom gained on removing the shifter seal - don't keep us in the dark 

[Justin_NJ]

Chris, any advice on getting the shifter seal off? 

Did you put in a spacer as per the FAQ?
http://www.sohc4.us/forums/index.php?topic=264.0

Did you stick with the same oil after you fixed it? 

[DRam]

Yeah Chris.  Be a pal and let us know how to get that seal out.  Then if it ever turns out that I know something I'll tell you.

DRam

[Einyodeler]

If needle-nose pliers don`t work you can put a thin drywall screw into the old seal and pull it out that way , worked for me.Be very careful not to scratch or gouge the seal seat area.

[pmpski_1]

Getting the seal out is one thing ... Chris did you say it took 5 minutes to get the new one in? How'd you do it?

[Chris Liston]

Okay, here it is.  and it does work.  The factory seal actually has an aluminum ring just below the rubber so it keeps its shape.  You take a small (1/8 or 1/4") flat head screwdriver and lightly tap it with a hammer.  This will puncture the alum ring.  Then you just twist the screwdriver alittle, may 1/8 twist maybe less and pull it out.  Sounds evasive but its the only way its coming out.  take a clean shop rag and wipe the area down and then carefully take your new seal and slide it over the shifter shaft.  I put some plastic rap over the edge of the knurled end so as not to scratch or gouge the inside of the new seal.  Push the seal back into the whole.  Now, I didnt use a tap but what I did use was a handle bar end.  I had just replaced my bars a day earlier.  The open end of a handle bar fits perfectly over shifter shaft and meets perfect to the new seal.  You dont need to go crazy here.  I just lightly pushed the new seal into place.  I was scared the entire time as I've never done anything like that but it worked out and no leaks. 

While you have the sidecover off is a great time to remove all the crud for years of riding too.  I think my bike lost 5lbs after I cleaned the back side of the case

[Chris Liston]

As far as oil I went back to regular dino oil.  10w40 auto oil.  Was talking to a mechanic and he said it would be fine.  Its what I've been putting in the bike since I did the first change a few years ago.  My cousin uses it in his 77 KZ750B and its fine.  I figure back in 1976 they had 1 type of oil and it was good for everything.  I know my bike was louder when I had the Honda oil in it. 

[Justin_NJ]

While I'm waiting for the shifter seal to arrive by mail, is there any chance that putting in regular non-synthetic auto oil might seal the leak? It only started when I put in the Honda GN4 oil....

[pmpski_1]

Hey, can someone tell me a bit more about the spacer? I don't understand the concept here. How long is the spacer? Is is supposed to fit Over the shaft, between the seal and the cover?

Thanks

[Chris Liston]

usually once something starts leaking its going to leak no matter what you put in.  Best bet is just change out the seal. 

[Justin_NJ]

Chris, I'm going to try to fix this leak this weekend.  As per the FAQ, did you add a rubber spacer to the gearchange shaft?   And what brand dino oil did you end up using?  Thanks, J.

From the FAQ:
7. Prior to re-installing the gearchange lever, slide a rubber spacer (similar to a garden hose washer) onto the gearchange shaft right up against the engine case. THEN install the gearchange lever. This will limit lateral (sideways) movement of the gearchange shaft, thus reducing the chance of the new oil seal from getting caught up on the shaft and gradually pulled out of its insert. Make sure that the gearchange lever can still move freely up and down - just not sideways.