1. Missed the live Ask the Expert event?
    Catch up on the conversation about fertilization strategies for success with the experts at Koch Turf & Ornamental in the Fertilizer Application forum.

    Dismiss Notice

Backpack motor seized

Discussion in 'Mechanic and Repair' started by jeffyr, Dec 21, 2002.

  1. Doc Pete

    Doc Pete LawnSite Gold Member
    Messages: 3,469

    You can try putting some "liquid wrench" down the plug hole and let it overnite, as already suggested. Also, try taking a "soft object", like a wooden dowel, and put it in the plug hole and "gently" tap on it to "break free" the ring.
  2. landman

    landman LawnSite Member
    from NJ
    Messages: 110

    Rebuild it if you have to new piston/head, gaskets ect all redmax parts should cost about $140.00 about 1 hour labor and your good to go. We rubuilt 3 of them this season and saved about $1500.00 instead of buying 3 new blowers.
  3. jeffyr

    jeffyr LawnSite Senior Member
    Messages: 876

    I put the oil in tonight and will give it a chance to soak. I gave the piston a couple of shots 30 min after adding the oil because I am impatient and it didn't budge. Hopefully a day or two soaking will loosten it up.

    Hate to sound ignorant....but what would be the difference between a shortblock and replacing the piston, rings, head, and gaskets ? What else comes with the shortblock ?

    Thanks for the input .....and answers to all the questions.
  4. General Grounds

    General Grounds LawnSite Senior Member
    Messages: 902

    :blob3: jeff, with the short block you get a new motor, minus the muffler,carb, coil, you take them off of you dammaged unit and place them on the short block, that why i suggested the gasket kit some gaskets dont come off so its just easy to replace them all. woolaa new blower
  5. Doc Pete

    Doc Pete LawnSite Gold Member
    Messages: 3,469

    Take off the muffler..... if you can see the piston is galled to death, call it a day.
  6. jeffyr

    jeffyr LawnSite Senior Member
    Messages: 876


    Galled to death :eek: We'll see. I will let you know when I look inside.

    Thanks again.

  7. jeffyr

    jeffyr LawnSite Senior Member
    Messages: 876

    A quick update with a followup question :

    I let it soak overnight with some 2 stroke in it and gave it a few shots with a hammer and dowel as suggested. Worked like a charm. Great suggestion !

    However the starter is tough to pull as if the piston or rings are rubbing (I am guessing that's what it is given the problem). I only pulled 4 times to take a look inside and recoat with more oil.
    So what is my next step ? Rings ? Piston ? Head ? I know I will have to tear into it to answer these questions and won''t have time until the weekend. Is there a good book or manual that one of you can recommend for rebuilding ? This is new ground for me.



    Merry Christmas !

  8. xpnd

    xpnd LawnSite Senior Member
    Messages: 378

    How many back packs do you have? Just one or several? If there is only one in your inventory are you prepared to have this one go down during the season on probably the most inconvienent day? Better to bite the bullet and short block the machine even if it works albeit roughly today. IMHO you are saving pennies today to spend dimes tomorrow in terms of labor and lost time when you should be working making money.
  9. jeffyr

    jeffyr LawnSite Senior Member
    Messages: 876


    Since it is the winter here and I will not need this until the beginning of march, and I do have another identical backpack plus a backup for the fall I figured I could learn something and fix it myself. If I brought it to a shop and they put a new piston and head on would you trust it ? If so, what's the difference between me doing my own repair and having someone elso do it ? I am asking questions so I can find out exactly what I need to do.... so I can start "saving pennies today to spend dimes tomorrow in terms of labor and lost time when you should be working making money". :rolleyes: This world is too disposable.

    This is the "Mechanic and Repair" forum I came here for advice on repair.
    BTW: I found a link to rebuilding a 2 stroke motor for an rc car. I was reading in an rc car forum that they use handheld leafblower engines. Here it is if anyone is interested : http://www.hpiracing.com/walkthroughs/engrebuild.htm


    SCAPEASAURUSREX LawnSite Senior Member
    Messages: 835


    It does not sound like its your oil that caused the problem, unless you were running it for days on a heavy mix.. That would just casue it run bad and may cause alot of build up and such.. SOunds to me like when you were servicing it for winter, you may have knocked a piece of dirt or such into the machine when checking the air filter ?? Something may have got in there scored the piston wall and caused the rings to over heat and then freze up or maybe a bearing went bad on the crank ?? Call me and come over one night or over the weekend and we will tear it down and see what happend inside and then we can make an educated decision as to how to go about fixing or discarding it.. But my guess would be a short block and a carb kit... But let s have a look see inside.... Talk to you later....

Share This Page