93 WXC 610 Oiling/ Engine case blowout?

Discussion in 'Older Single cams' started by Braaapster, Sep 26, 2015.

  1. Braaapster Husqvarna
    B Class

    Location:
    San Luis Obispo, CA
    Husqvarna Motorcycle:
    '93 WXC 610
    Other Motorcycles:
    '95 XR600R, '03 DR650
    Hey everyone,

    I recently picked up a '93 WC 610 and I am in the process of going through it. I had an oil leak on the left side of the engine case coming from the top of the plastic cover. Unfortunately, the threads on one side were stripped, and the gasket was pretty much done. I re-tapped the threads, and replaced the gasket, but the oil leak would not go away.

    As I had the cover off, I noticed that there was a hole on the inside (see pic). Was this originally a small hole that has now been blown out to a larger size, or is that hole strictly due to some sort of damage to the engine? I'm guessing that the hole is causing the oil chamber to become too pressurized for the plastic cover to hold. I've heard that the oiling system on the older Huskys is kinda funky, but even this surprised me.

    IMG_20150919_140706.jpg

    As a side note, the engine runs well, but there is just a continuous drip of oil coming from the top of the opening where oil leaks through the cover.

    Has anyone else had this problem? And does anyone know if that hole is supposed to be there? I would appreciate any advice.
  2. DaveM Husqvarna
    AA Class

    Location:
    Adelaide, Australia
    Husqvarna Motorcycle:
    2001 TE 570
    Other Motorcycles:
    Motorised Bicycle
  3. rancher1 Husqvarna
    Pro Class

    Location:
    WA
    I agree with dave take the picture a little further back so we can tell what part of the motor it is on. I think it is the magnet that goes at the bottom of the cylinder. I have seen those leak before. Get a new gasket and coat it with oil resistant sealer that may cure it for you.
  4. Braaapster Husqvarna
    B Class

    Location:
    San Luis Obispo, CA
    Husqvarna Motorcycle:
    '93 WXC 610
    Other Motorcycles:
    '95 XR600R, '03 DR650
    Sorry for the initial lack of info. The plug that covers the opening is part 19 on drawing 2 of the parts fiche.

    I took some more photos photos to help illustrate my question. The plug location is circled in red.
    IMG_20150929_161502e.jpg

    My original question was regarding whether the inside of the chamber that the plug seals originally had a hole or not.

    This is what it looks like after removing the plug.
    IMG_20150929_162015.jpg

    Back to my original question, was that hole originally a small one solely for oil circulation and has now been blown out somehow? If not, any idea what would cause that? Finally, would that hole on the right be causing my oil pressure to become excessively high and cause the leak at the top of the plug?

    If someone has a 610 in good shape I would be very grateful if you could snap a picture of what underneath the plug looks like for comparison.
  5. Up-tite Husqvarna
    Pro Class

    That should be a rubber plug, held in by the cover with the magnet in the end.
    Reach in and pull it out once out you will see how it works.
    Leaks because screw holes are stripped out .
    Not a blow out just got to thin when hole machined.
    It's fine just that the old RAL system pulled oil from that hole later models pulled oil from back of and below cylinder.
    Looks like magnet is stuck in the end of the plug, check to see if magnet is still on the cover plate.
    The magnet goes in the end of the cover plate.
    Fix threads cut gasket out of wheaties box put rubber plug back in make sure tit on rubber plug goes in hole, and magnet is in the end of the cover plate this holds the plug in.
    Later George
    justintendo likes this.
  6. Braaapster Husqvarna
    B Class

    Location:
    San Luis Obispo, CA
    Husqvarna Motorcycle:
    '93 WXC 610
    Other Motorcycles:
    '95 XR600R, '03 DR650
    Thanks for the help George. I didn't take a picture of it, but the magnet is stuck on the plug so I do have it.

    I'll re-tap those holes, replace the gasket, and hopefully that fixes my leak.

    Rancher1, thats a good idea, I'll probably coat the lip of the cover with some sealant too.
  7. Braaapster Husqvarna
    B Class

    Location:
    San Luis Obispo, CA
    Husqvarna Motorcycle:
    '93 WXC 610
    Other Motorcycles:
    '95 XR600R, '03 DR650
    Hey everyone, just a quick update.

    This weekend I was able to tap new threads, cut a new gasket, apply some silicon gasket maker around the edges of the plug, and do a full oil change. I fixed my original leak, but unfortunately I noticed another oil related issue.

    I ran the bike for about 10 mins or so just to dial in carb settings and noticed some smoke coming out of the exhaust pipe. I was assuming that it was just a layer of junk burning off that had collected on the pipe over the 3 years the bike was in storage. I also noticed that the bike would smoke the most when running at idle. The smoke did not have the common blue tint for burning oil, and I want to think that the smoke was just due to the bike running rich at idle. When I would increase revs, the smoke would clear up. While looking for the cause of the smoke I noticed this on the right exhaust header.
    20151023_015841.jpg

    And here is a closer view of the leaking oil.
    20151023_015848.jpg

    I mentioned the recent oil change since I would imagine that the oil leaking out would be honey colored, not jet black as seen in the photo. Similar to the picture, I also noticed black oil splattering on the side of the engine block where the exhaust headers join the rest of the exhaust system. I'm not familiar enough with this bike and oiling system yet to decide where to begin a proper diagnosis. And a side thought... I searched the parts fiche for the bike looking for a collar for the header where it joins the engine block, but I couldn't find anything. Interesting how there are two threaded holes around the exhaust port, but the headers are only held in with the bolt on the top.

    Is this issue fairly common on older Huskys? Can it be ignored, or is this a tell-tale sign of major damage in the near future? My biggest fear is dropping a valve and not seeing this as the first warning sign, but at the same time, I'm dying to take the bike out for its first ride. If anyone has any experience or advice, I would appreciate it. Not quite sure what to do from here...
  8. rancher1 Husqvarna
    Pro Class

    Location:
    WA
    Are you sure the oil didn't leak down from the valve cover above ? I have had that problem before.
  9. Up-tite Husqvarna
    Pro Class

    Just ride it. Get couple hundred on it then we'll have a better idea if anything.
    Later George
  10. Braaapster Husqvarna
    B Class

    Location:
    San Luis Obispo, CA
    Husqvarna Motorcycle:
    '93 WXC 610
    Other Motorcycles:
    '95 XR600R, '03 DR650
    An update on the woes of my leaky and smokey Husky.

    As of a couple months ago I decided to get a leak down test on the bike to see if the black soot from my previous post was oil or not. Turns out the engine is still pretty tight with just 8% pressure loss, which is not bad for a bike from '93 with pretty much unknown maintenance records. Since a significant amount of oil leaking past the valve guides seemed unlikely based on the leak down test, I decided to just live with the soot dripping from the header and get some hours on the bike as George suggested. When the bike is warm it smokes at idle, and throttle roll on, so I've been experimenting with jetting to see if I could stop the smoking by leaning it out slightly.

    Yesterday I tore down the bike, and decided to pull the right side header to clean off some of the soot that had dripped down onto it. I then took a look into the right side exhaust port, and I believe I found the root of my smoking/ soot spewing problem. Not a pretty sight...

    exhaust-opening small (1).jpg



    exhaust-opening small (2).jpg

    Based on all that buildup I believe I can assume a couple things: 1. The bike has been running rich for a very long time, and 2. the carbon is the cause of the smoking when the bike is hot. I only noticed the carbon drip from the right header since it was slightly loose and allowed liquid to drip through, so the left side probably looks about the same around the exhaust valve except with no visible drip. I'm curious to see how the piston looks based on what I've found here.

    Looks like I'll need to pull the head to clean it up properly. Anyone have suggestions on a good technique to do so? If its more trouble than its worth as a DIY project I wouldn't be opposed to sending it somewhere to get it done professionally.