a wee bit of oil

R

rescue50

XS400 Enthusiast
Messages
41
Reaction score
0
Points
6
Location
Rice Lake, Ontario, Canada
Finally got to take the bike out for a spin. Ran pretty well, though my clutch adjustment was purely done. Had to release the clutch lever nearly 100% before clutch would engage. When I got back home and parked the bike, I immediately noticed oil dripping from under the engine the picture of the oil on the road represents about two minutes worth. Once the engine cools, the leaking stops. I did see some oil welling up near the joint between the clutch adjuster cover and the crankcase. (see pics)
 

Attachments

  • IMAG1018.jpg
    IMAG1018.jpg
    304.8 KB · Views: 261
  • IMAG1014.jpg
    IMAG1014.jpg
    225.9 KB · Views: 309
  • IMAG1017.jpg
    IMAG1017.jpg
    207.1 KB · Views: 289
Looks like it is coming out of the crank case breather.

Either your oil level is too high or worn piston rings are causing blow by; pressure sneaks past worn piston rings and goes into the crank case; this forces oil out the breather.

You'll want to verify that is it in fact coming from the breather and check your oil level first; make sure you're measuring it correctly. The bike should NOT be on the side stand; it needs to be vertical and on a level surface.
 
Certain piston and ring sizes in particular are difficult or expensive to acquire.

If it comes down to it, it may be less expensive to buy a new top end with some used pistons/rings in good shape. This swap can be done with the engine in the frame. I have done it on my '78 a few times for cleaning purposes.

Anyway, if you suspect blow-by you might want to check the compression; do a wet and dry test.
 
In the first picture it looks like there is no hose on the crankcase vent port. Or at least it is not visible. My 81 has a hose on that vent port connected to the "H" hose from the carbs to the individual air elements.
 
Won't let me post a video, if you look at the first picture, there I'd a slight gap been the crankcase and the attitude cover the oil wells up from inside the cover through that gap when the engine is running. I'll try to highlight the spot on the photo.
 
Put the video on YouTube, then link it here. Use the Advance button below here. Just when you post it, select the options where it is not for everyone, and only people with the link can see it.
 
When you say gap, you mean the starter wire hole? if that is the case, you have two things going on,
  1. Starter o-ring seal is shot.
  2. The drain hole below the starter is clogged.
  3. Potentially your starter is floating in oil
 
Before we freak out, lets check the basics, do you have a oil sight glass, or dipstick, make sure its full, and doesn't smell of fuel.

It will be easier to work on that spot of the bike with the fuel tank removed, and the carbs removed. (gets easier with practice.)

Once you take off that shiny cover, You can not removed the starter. but it will tell you if my first hypothesis is right. If you were to attempt to remove the starter, the starter chain will fall into that stator assembly, and potentially get strung up on every that moves in there.

So take it in small steps. if your going to do anything.

There is a chance you just have too much oil.
 
thanks for the advice. Here's the video link


As for the oil, the bike had a sight glass, though it's impossible to see through it . That said, An oil change was done about two hours of riding ago .

Posted via Mobile
 
That is a seal leak. If you have the RTV, a cereal box, there is cut outs of the gasket in the laboratory, for you to make your own gasket. You have to take off remove the drive sprocket cover, the Yamaha plate, stator assembly,

With your newly made gasket, I have recently started to put RTV on both sides, if you have to run, to get some, I use the black stuff, with a preference to the Yamaha lube version. (it doesn't dry out like some others.)
 
rescue50 said:
thanks for the advice. Here's the video link


As for the oil, the bike had a sight glass, though it's impossible to see through it . That said, An oil change was done about two hours of riding ago .

Posted via Mobile
Click to expand...

How do you check the oil? Try to find a dipstick off an earlier model bike. The 76-77 xs360 and the 77-79 xs400 has them. Or just clean the sight glass by removing the cover a cleaning it. If your getting a gasket set you can do it then. Having pressurized oil that far up the alt. cover seems to be a bit strange. When the bike is full with the proper amount it only sits off the bottom of the motor about 2-3".
 
A couple of weeks ago, I changed the oil, draining using the port on the side of the crankcase. (I understand now that the one on the bottom is the preferred drain.) Almost no oil came out, not even when I removed the filter. I assumed that last year's oil had either leaked out or burned off. I changed the filter and added 2 litres (2000cc) of oil. Is it possible that that much oil somehow did not drain out of the block?The bike was on the center stand during the oil change. Xs Chris, thanks for the advice about the dipstick, arfstrom, I tried to follow the link to the gasket, but keep getting an administrato privilege error, or something to that effect.
 

Similar threads

CalgaryStreetBob
***NEW BIKE NEED ADVICE*
Replies
1
Views
632
tstidham
tstidham
Ben Thompson
82 XS400J/Maxim - Oil Problem - Top end not getting oil
Replies
9
Views
1K
tstidham
tstidham
B
XS rebuild back on track..maybe!
Replies
5
Views
769
JPaganel
JPaganel
R
Hello Everyone.
2
Replies
30
Views
3K
amc49
A
tstidham
Re-Ring, Dodge VR and Starter Clutch Springs
Replies
12
Views
2K
tstidham
tstidham
Back
Top