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Toro 2 cycle 21" piston repair

Discussion in 'Mechanic and Repair' started by dlandscaping, Sep 5, 2005.

  1. dlandscaping

    dlandscaping LawnSite Senior Member
    from mass
    Posts: 835

    I have two Suzuki two cycle engines, one has bad rings and piston, and the other one has a bent crankshaft. I was going to just get each's respective part(s) and have 2 21"s. Since I have never worked on a 2 cycle before, how do you get the piston with the rings into the casing. Do you have to put the tool around just the piston, and then push it in. And then connect the crankshaft back again, or is there another way. The tool I am talking about is a hollow cylinder that has bolts that make it tighten.
     
  2. Restrorob

    Restrorob LawnSite Fanatic
    Posts: 11,024

    A ring compressor is the easiest and quickest way to install a piston, Although the one you explained sounds like something from the 20's.
    The idea is to install it on the piston over the rings with just enough piston skirt sticking out to start into the cylinder, Then while holding the compressor flush with the top of the cylinder at all times push or tap the piston in using a wood hammer handle tapping lightly until the piston is in the cylinder then reconnect the rod to the crank.
    I would recommend de-glazing the cylinder and installing new rings, The wear will most likely be different between the two cylinders and the used rings may not seat properly.
     
  3. dlandscaping

    dlandscaping LawnSite Senior Member
    from mass
    Posts: 835

    I took the other one apart, the one that I suspected had a bent shaft. It doesnt seem bent, but it did shake when running, after it hit the pipe thing. Its $250 for a new crank shaft, is there any way to make sure that it is in fact bent. When I took half of the shot block off, the crank shaft and the piston moved easily without scraping or resistance.
     
  4. Restrorob

    Restrorob LawnSite Fanatic
    Posts: 11,024

    I don't really know of a good way with the engine apart, What I do on all small walk behind mowers before I do any work on them is remove the spark plug and have a helper tip the mower up and pull the rope while I watch the center blade bolt for any wobble. If I find there is I send it down the road for lability reasons. If you say it shakes after hitting a pipe you can bet it's bent just enough to cause problems.
     
  5. mower_medic

    mower_medic LawnSite Member
    Posts: 77

    Most ring compressors won't work on a 2 cycke engine like that. If you look, you will see that the end of the cylinder is tapered. If you lubricate the cylinder and the piston and rings well, the cylinder will compress the rings as you slide the piston into it.
     
  6. lawnmaniac883

    lawnmaniac883 LawnSite Silver Member
    Posts: 2,613

    That is true for a trimmer or blower, but this is a 2 stroke mower...good point though whether it is true for this application or not.
     
  7. mower_medic

    mower_medic LawnSite Member
    Posts: 77

    It works, I've done it many times before.
     

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