1. Dismiss Notice
  2. Hey Facebook people... We've created a group for XS400.com members to connect. Check it out!
    Dismiss Notice
  3. Want an XS400.com t-shirt? Go to the store to order. Limited sizes and quantities available.
    Dismiss Notice

Just bought a '77 XS360. Not quite a basket case but...

Discussion in 'The Garage' started by Spiffarino, Dec 21, 2019.

Tags:
  1. Spiffarino

    Spiffarino XS400 Enthusiast

    Here’s the donorcycle. As you can see there are copious amounts of troll snot holding in most of the oil, but it does fire up. It’ll need all new gaskets and some bolts are missing. Also, somebody did the same stupid wiring trick as my other bike by bypassing all but the main fuse. I guess they know they’ll get stranded but at least they can warm themselves beside a burning motorcycle until help arrives.
     

    Attached Files:

  2. xschris

    xschris a lifestyle not a trend Top Contributor

    Make sure to clean the sump out well as that troll snot gets into everything. Never use that stuff to fix gasket issues!!! Your 400 vin number is only about 100 off from mine. The yamaha dealer told me that the first run of u.s. 82 sohc xs400's was short. Then in 83-84 they sent out another run of leftover 82's with a higher vin number. Something I never knew. I did know they did that with the xs650 for 83-84.
     
    Spiffarino likes this.
  3. Spiffarino

    Spiffarino XS400 Enthusiast

    I wrestled the motor out of the 360 and pulled just about everything off the frame. The holes in the swing arm bolt are very grimy and the bolt itself has some rust. It looks like it can be cleaned off with a wire brush, but do you think I should replace it anyway?

    Next step is to remove the oil pan and see how it looks. Not expecting pretty.
     

    Attached Files:

  4. xschris

    xschris a lifestyle not a trend Top Contributor

    Replace the swing arm bushings, seals and bolt if there is any rust or gulling. The later xs400 bolts have grease able fittings on the ends to keep them full and lubed. Mikesxs has bronze bushings and inner bushing tubes that work well.
     
    Spiffarino likes this.
  5. Spiffarino

    Spiffarino XS400 Enthusiast

    Thanks, xschris. I definitely will replace. I took off the crankcase cover and it's very clean. I haven't taken out the oil pump yet, but the the oil was very clean when it was drained. Maybe somebody cared about the inside more than the outside.


    And yes, of course it's not an oil pan. I don't always proofread before I hit "reply" so expect more of this. :/
     
  6. xschris

    xschris a lifestyle not a trend Top Contributor

    Your sump screen will catch any large stuff. It's under the motor with 6 small bolts in it. I would leave the oil pump alone.
     
    Spiffarino likes this.
  7. NewHavenMike

    NewHavenMike 1976 XS360C Top Contributor

    The bolts for the sump screen will strip the threads in the case very easily so dont over-tighten them.

    I wouldnt touch the oil pump either, never have.
     
    Spiffarino likes this.
  8. xschris

    xschris a lifestyle not a trend Top Contributor

    Unless you oil pressure is bad you don't need to remove it. There are specs for clearances in the manual for the pump that can be checked. You really only need to remove the plate off the front to get to it.
     
    Spiffarino likes this.
  9. Spiffarino

    Spiffarino XS400 Enthusiast

    Thanks for the advice!

    I wasn't having any luck with the plate as it's pretty well frozen and figured the oil pump might possibly be a way in. No way I'll take a screwdriver to it or any other sharp metal object. Any top tips for removing the plate?
     
  10. xschris

    xschris a lifestyle not a trend Top Contributor

    After you remove the 6 bolts just tap it with a rubber mallet from the side. Make sure you get a new sump plate gasket as that one will be no good if it's sticking that bad. Most likely it's never been off. I would use the upgraded sump screen that will be in your xs400 motor if you use that motor. The 80-82 bikes use a metal housing instead of rubber poles to hold them into place. The rubber ones get soft and will not hold the screen as well.
     
    Spiffarino likes this.
  11. Spiffarino

    Spiffarino XS400 Enthusiast

    I don't know how many times I can say "thanks" before you get tired of it. Consider it implied in every "like" I give you. There will be many.
     
    xschris likes this.
  12. xschris

    xschris a lifestyle not a trend Top Contributor

    Just want to help the best I can. I like to see these bikes stay on the road.
     
    Spiffarino likes this.
  13. Spiffarino

    Spiffarino XS400 Enthusiast

    Got the screen out and it's super clean; there was nothing trapped in it. Doubtful it's been replaced as hard as the cover was to remove. The cover inside has a very thin layer of dark grit which I would expect after 43 years. Once the gaskets arrive I plan to start at the top and see what's causing the compression issues. I'll get more photos up once the motor's apart.

    So far this project has been a blast.
     
    xschris likes this.
  14. Spiffarino

    Spiffarino XS400 Enthusiast

    Well then, I will take you up on that offer!
    Could you - or any watching this thread - tell me what all the parts are on a 76-80 era drum brake front axle? The '77 seems to have a big gap and the threaded part of the axle stick out further than the hole for the cotter pin. I've looked at a parts breakout but haven't had luck identifying what it needs.
    Unfortunately I can't get you a photo of the axle as the bike is already down to the bare frame.
     
  15. xschris

    xschris a lifestyle not a trend Top Contributor

    Pics of the front of a drum bike. This is my 79 but all drum 360/400 where mostly the same.
    DSC03785.JPG DSC03786.JPG
     
  16. Spiffarino

    Spiffarino XS400 Enthusiast

    Hmm...it doesn't look any different. I guess I'll have to use the donor bike as a template and figure out what I'm not understanding.

    In other news, I got the cam cover and head off the 360 and while it needs a valve job...
    IMG_4706.jpg IMG_4708.jpg
    ...that burn mark kind of looks like a blown head gasket. I've only seen them on cars and even then it's been more than 30 years so I'm not 100% sure. If so, no matter. I have a box of brand new engine gaskets.

    I just hope the valve seats are salvageable, otherwise this may be the end of the line.
     
    Last edited: Feb 7, 2020
  17. Spiffarino

    Spiffarino XS400 Enthusiast

    I've run into a road block.

    While not showing signs of any scratches or obvious damage, the cylinder walls are completely smooth...no cross-hatching at all. The cylinders have to come off but it won't budge. I've done the rubber mallet treatment and even tried levering it lightly with a small but strong piece of lumber. No movement detected whatsoever. I've sprayed it with Blaster a few times but no love.

    Tips aren't just for cows and mohels, but they're always appreciated.
     
  18. xschris

    xschris a lifestyle not a trend Top Contributor

    Try getting some power blaster spray down the studs. Gentle taps with a rubber mallet at all angles then repeat. It may take a while, don't rush.
     
    Spiffarino likes this.
  19. Spiffarino

    Spiffarino XS400 Enthusiast

    That is exactly what I did earlier in the day (plus a little heat from a propane torch) and it worked just as you described! The bottom gasket is baked onto the cylinder

    There is a good bit of carbon build-up on the pistons, particularly the left one. All four compression rings broke as I removed them. Very brittle. The good news is the cylinder walls have no scratches and the pistons look pretty good (aside from the hard black stuff). Just need to measure the cylinder diameters and get them honed.
     
  20. Spiffarino

    Spiffarino XS400 Enthusiast

    The carbon build-up is really bad. I've soaked the stuff in diesel fuel and sprayed it with Blaster but there's still a lot of crust. The valves are especially hard to clean. What works best for you?
     

Share This Page