1. Husqvarna Motorcycles Made In Sweden - About 1988 and older

oil drain plug,threaded

Discussion in 'Vintage/Left Kickers' started by patgas, Apr 1, 2010.

  1. patgas Husqvarna
    A Class

    Location:
    dolgellau/ wales
    first disaster on my engine rebuild,someone has threaded the oil drain plug,i think its about m14 but not 100% could you guys confirm 79 or 390,and what hav you guys done as repair is helicoil satisfactory or re tap and use bigger plug ?cheers(thread pitch and size needed):thumbsdown:
  2. oldhuskychuck Husqvarna
    A Class

    Location:
    Denver Co
    well,
    yes i have, however, a helicoil will leak, no matter how hard or good a job you do, it will leak..been there done that.
    not sure were your going to get a larger plug, ill have to check and see, maybe the old 4 speeds have a bigger one..not sure, i do know that the 02 and newer KTM,s have larger plug, you would have to drill and retap it for that plug.
    what i ended up doing.. was have the hole welded, then redrill and tap.
    find someone that can weld Magnesium...its a art form..and cost a bit...
    but it doesnt leak when done right.
  3. fran...k. Husqvarna
    AA Class

    Location:
    eastern ct
    Husqvarna Motorcycle:
    420ae 98wr125 2004wr250 others
    Other Motorcycles:
    electric freeride 1993 yam gts
    Never been there. Never done that. Here in the USA we have pipe thread stuff for plumbing. I had a Dodge van with a pipe plug for the fill on the side and think on the drain as well but not sure about the drain, I lost the fill plug or loaned the van and the other guy lost it. Pipe thread is tapered, I know one of the guys I put arrows up with for an enduro lost his drain plug and said he went to a pipe plug. As for the helicoil, I have seen this thread elsewhere and believe if you install the helicoil (drill out and tap for the thing on a machine so it is totally square the washer should seal same as before, the threads on a machine screw do not create the seal like the threads of a pipe. Of course you can't over torque pipe stuff if the outer threaded part can't take the stresses of the tapered plug acting like a wedge. This is why hydraulic connections are often sealed with o rings. You have to be careful not to get the wrong hydraulic fitting as they often get mixed up at places where they are for sale.

    Fran
  4. skythrasher Husqvarna
    AA Class

    Location:
    NW Arkansas
    There are many types of inserts that can be used for many different applications. What most people refer to as a helicoil (which is a brand name) is a spiral wound insert thats intended use is on an application that does not have to hold fluid or pressure. These are sometimes used not as a repair, but as preventive measures where conditions are prone to thread damage.

    There are solid inserts (sold under the helicoil brand, even) that can be used that are installed and then sealed by swaging them in place. Usually one would apply a small amount of RTV to the external threads, then swage. These type inserts will hold hundreds of pounds of pressure at hundreds of degrees temperature. This is a type similar to those used to repair spark plug holes in cylinder heads.

    I am a machinist at a power plant and have had good results from several types of inserts. As stated above, however, it makes a difference in how precise you are on the install. I would not be afraid to tackle an oil plug with hand tools, given I had a proper type insert.