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yojoe2

Broken Connecting Rod on 9hp Tech?

Yojoe2
11 years ago

9 year old Craftsman snowblower with 9hp Tech snow king engine. Ran great last night, shut down as normal, stored inside. Went to use it this morning, engine turned just a bit, then the brand new electric starter buzzed.
Tried recoil start, would not turn at all. Took off the cover over the pulley/crankshaft area, tried to turn with a wrench, no go. Took the tension off the pulley/belt also, to make sure it was, in fact, the engine that would not turn.
Can turn it counter clockwise about 3/4 of a revolution, then it stops, will turn back clockwise the same amount. Always stops at the same place. Took recoil off, could not see any obstructions, still will not turn, took spark plug out, will not turn. Does not appear that the piston goes up and down when I turn the crankshaft as much as I can. Oil level is good.
From what I found on the web, it sounds like it may be a broken connecting rod, which is probably beyond my repair ability, and I just don't have the time to try it right now. Anyone know if I'm on the right track here and/or about what it might cost for a repair (labor)? Just trying to figure out if this snowblower's time is up, too bad though it's in good shape, except for the engine now. Thanks!

Comments (18)

  • baymee
    11 years ago

    Can turn it counter clockwise about 3/4 of a revolution, then it stops, will turn back clockwise the same amount. Always stops at the same place. Took recoil off, could not see any obstructions, still will not turn, took spark plug out, will not turn.

    Typical of a bad rod. You should be able to see the piston in the plug hole and it's probably at TDC or won't move. I never heard of a 9HP Tec.

    If you can get a replacement rod and possibly a crank (my crank was scored), they aren't too hard to swap out for a mechanic. Otherwise, forget it.

    You might be able to get a shortblock from Tulsa engine wareshouse, or smallenginewarehouse.com

  • tomplum
    11 years ago

    Sounds rod like as baymee says. If you have a good view of the top of the piston, and it doesn't move- you are likely right on that something internal has gone awry. Be certain that the starter gear is disengaged from the ring gear as you try to turn it to. Pulling the belt cover off isn't a bad idea either and having a look. You would hate to have the drive iced up and the belt not being able to turn emulate an engine issue.

  • Yojoe2
    Original Author
    11 years ago

    Thanks guys, I'll take the belt cover off tomorrow to be sure nothing is binding there.
    Sorry, I was trying to abbreviate Tecumseh as Tec, guess it didn't work :)
    I appreciate the quick responses from you two.

  • aj_allen
    11 years ago

    Pull the starter & look for a bulge in the block or missing teeth on the starter. If there is a bulge broken connecting rod. Missing teeth on the starter the missing teeth may be stuck under the flywheel causing it to jam.

  • rosemallow
    11 years ago

    Going by what you said about using it and then you stored it.
    It may not be the connecting rod. You have to remove the starter and fan cover to see if something is hitting. A 3/4 turn of the flywheel and looking at the piston is really hard to tell if it is moving if it is at TDC.
    If the connecting rod is broken you can take the spark plug out. Take a brass rod or aluminum rod push through the spark plug hole and push the piston down. If you can do this and the flywheel does not turn then you have a broken rod.

  • Yojoe2
    Original Author
    11 years ago

    Ok, took fan cover off and can see something loose, preventing the flywheel from spinning. Looks like a black magnet with copper wire wound around it, so something to do with the electrical/alternator?? Anyone know what it is or where it belongs? Is taking the flywheel off something I can do with basic mechanics tools or do I need something special?
    Many Thanks!

  • baymee
    11 years ago

    To make my explanation clearer, by turning the crank, the piston will move up to the top and since the rod isn't there, it won't come back down.

    I would just pull the plug, move the crank, and if the piston doesn't move, you know what it is.

  • Yojoe2
    Original Author
    11 years ago

    Baymee, It looks like we posted things at the exact same time, If you're still on here, can you read my post just above your last one? Thanks!

  • baymee
    11 years ago

    Sounds like you lucked out. I've never worked on a 9HP Tec., but you probably need a puller to get the flywheel off. Then a torque wrench to put it back. Look on you tube. I'm sure there are many videos about removing a flywheel.

    I'd rather have your problem than a broken rod.

  • bill_kapaun
    11 years ago

    It would be helpful if you identified the Model# of the engine.
    That way, we could maybe refer you to a pdf file for the service manual.

    Possibly, the Sears# might work. Probably in the format of 917.xxxxxx

  • Yojoe2
    Original Author
    11 years ago

    Sears Model 143.049001, which I think is the same as HMSK90.

    Thanks

  • bill_kapaun
    11 years ago

    Click the link

    Here is a link that might be useful: manual link

  • Yojoe2
    Original Author
    11 years ago

    Awesome! Thanks for the link to the manual. I got a puller that looks like it will work. I will pull off the flywheel tomorrow. I think the part that is loose inside is a piece of the alternator, no idea why that would break off though.
    If that is the case, can I just remove what is left of the alternator and run it that way? My unit does not have a headlight, or anything else that I can see that the alternator is being used for, I think the engine just came with it.
    Thanks for all the help!

  • bill_kapaun
    11 years ago

    Just to make sure it isn't the coil instead, why not wait until you properly identify what's broke.

  • tomplum
    11 years ago

    Ooh, a model w/ a lighting coil. You will may find a magnet off the inside flywheel. On Sears parts, the lighting coil (611111) shows as available yet if the flywheel can be used. They show the flywheel (611093) as NLA. My distributor shows both as NLA. 32589 is the flywheel key number should it be damaged, tho it should be a standard steel key I would think.

  • Yojoe2
    Original Author
    11 years ago

    OK, got the flywheel off, the entire alternator coil is off and damaged. The cast post on the engine block that the coil attaches to busted off. So now, my question is: is the engine still safe to use even though this chunk broke off?? I hope my explanation makes sense. Under the flywheel, there are two posts that are cast into the block. This alternator was attached to one of the posts, that entire post failed and sheered off the block. Does anyone think this affects the integrity of the block itself? I don't want to fire it up and have it explode or something!

    Thanks again everyone!

  • Yojoe2
    Original Author
    11 years ago

    Put it back together and it started right up, ran good.
    A big thank you to everyone. It is so nice of you all to provide your expert advice to folks like me looking for a little guidance and help. I tore into this more that I would have otherwise, thanks to your advice.

    Merry Christmas and Happy Holidays to everyone!

  • baymee
    11 years ago

    If you tried to break off the post with a hammer, it would be just your luck that you'd have a hole in the case. But, as fate would have it, you probably have no serious damage.

    And a Merry Christmas to you.