new tthp problem

Discussion in 'eXmark' started by yard sloth, Sep 16, 2004.

  1. yard sloth

    yard sloth LawnSite Member
    Posts: 76

    I have a new tthp 36" mower with only about 10 - 15 hours. Today I noticed the big blade belt was bouncing and shaking kinda violently. I stood off to the side to see it and also noticed the front idler pulley bouncing around pretty bad. This can't be normal or good for the parts. Any ideas why it's doing this. It gets worse (or more noticable) if I lower the rpms. I don't have much faith in my dealer to fix anything so I hope you can give me some ideas on what to check. thanks
     
  2. eXmark

    eXmark Manufacturer / Sponsor
    Posts: 4,258

    Yard sloth,

    It could be a number of things. The belt, one of the pulley's (not limited to the belts and pulleys that appear to be the issue) as well as the engine. While you may not have much faith in your dealer I'd highly recommend that you take it into him on such a new machine.

    Thanks

    Terry
     
  3. dishboy

    dishboy LawnSite Platinum Member
    from zone 6
    Posts: 4,313



    My 03 I bought new this spring has the same problem, as well as the new units that were at the dealer when I started dealing with this issue.

    The Exmark Mechanic at my shop changed out a pulley, added a cone washer to the idler pulley and a new belt. This relieved the problem somewhat but now four months later I have a trashed belt that rides on the top of the deck idler pulley, the three or four inch wide pulley, and then drops at least 1/2 to 3/4in to the blade pulley. Why the belt is choosing this path is beyond me, I am sure this is what trashed the belt, or at least is part of the problem . To my dealers and Exmarks credit they are addressing my concerns so far as I have brought them. I went in yesterday and scheduled a appointment and they gave me a new belt.

    Terry, I hope your tech guys have addressed the issue and come up with a solution that fixes this problem, pulley bounce, and do you have a clue why my belt wants to ride on the top of the idler pulley when this is creating a severe angle to the blade pulley? I am cutting at 2.5 inch or the third hole.

    Thanks

    Tom
     
  4. eXmark

    eXmark Manufacturer / Sponsor
    Posts: 4,258

    Guys,

    Let me know the name of your dealer. One of the tech guys was telling me we had a similar issue being caused by the pump drive pulley(s). I'd recommend taking the unit to the dealer and having him look at the unit. If you pull the cold start kit chain and the shake decreases there is a good chance that the pump drive pulley could be causing the problem. To be certain you dealer would need to remove the pump drive belt.

    If let me know the name of your dealer I'll be certain to forward this information to him as well. You can PM me at terry.eckert@exmark.com

    Thanks

    Terry
     
  5. yard sloth

    yard sloth LawnSite Member
    Posts: 76


    I took mine back to the dealer for him to look at. He saw the shaking belt / jumping idler pulley and said it was "normal, they always have some bounce". But this is a very violent bounce which is obviously going to wear the belt and pulleys quickly. I tried to express my concern but he didn't care or want to help. That is what I expected from this guy. I will not go back to him. He also said if there is a problem that I caused it by hitting something and bent the blade or burned a low spot onto the belt. This dealer was very condescending and insinuated that if there was anything wrong, that it was caused by me. The mower has been barely used on my regular well maintained yards, I have not hit or bent anything. He did not even want me to take the mower off the trailer so I could show him how new, clean, unbent and not worn everything was.

    The problem with the pump drive pulleys sounds like what's happening on mine. While the mower is just idling, with blades off, the cold start chain is jumping and shaking, if I hold onto it I can feel and see the pulley shaking. When I pull the chain the shaking stops. Is there a competent Exmark dealer around DFW who will actually admit there's a problem and look into fixing it? The dealer I bought it from is Saginaw Rental, but I do not want to return to him. I need this mower to last, and don't want to prematurely wear out the parts.

    Thanks
     
  6. Jim H

    Jim H LawnSite Member
    Posts: 33

    I know this sounds silly, but I had the same problem when I first ran my tthp 36" and after changing the spark plugs it ran like a champ.
     
  7. eXmark

    eXmark Manufacturer / Sponsor
    Posts: 4,258

    YardSloth,

    If you would like I can recommend another dealer however I did recieve a call from our area rep whe had gotten a call from Saginaw looking for answers to your problem. Please let me know if you want to take the unit to another dealer or if you would rather go back to Saginaw.

    Thanks

    Terry
     
  8. yard sloth

    yard sloth LawnSite Member
    Posts: 76

    That wasn't Saginaw calling the rep, it was us trying to get some help. Thanks for calling my wife back and helping us find another dealer to take it to. As soon as the part gets there, we will take it in, thanks again.
     
  9. dishboy

    dishboy LawnSite Platinum Member
    from zone 6
    Posts: 4,313

    Terry,

    On my new 03 I checked the pump pulley by pulling the cold start release and did not see a change in belt oscilation or idler bounce.

    I took my machine in to Horizen in Boise Idaho and Jerry and I spent some time on the phone with Fred at tech. He had us raise the back of the deck to change the pulley angle. We went up and down a number of times and got the belt to come down the pulley at 2.5 inches relieving the severe angle. Jerry's blade height checker was homemade and IMO impossible to check a accurate deck rake with. I bought a blade checker and spent some condsiderable time re-setting my deck up as it had between 3/8 and 1/2 inch rake in it after bringing the machine home.

    I believe my problem is that at 1/8 to 1/4 deck rake at 2.5in cutting height the angle and design of Exmarks idler arm and pulley which is trying compensate a very wide cutting range. At anywhere between 1/8 to 1/4 inch deck rake the belt is at the top of the idler pulley and then drops at least 1.5 inches in six or seven inches to the first blade pulley.

    First off I like the cut with no more rake than mid way between 1/8 to 1/4 and going past there raises my cut past what matches up with my 21 and also leaves a ridge between passes on the left side of the mower. I never cut above 3in so if anything can be changed by a changing idler pulley's or something else I am game.

    Dialing in excessive deck rake to compensate for a bad design, bad run of idler arms is not a acceptable band aid, nor is replacing blade belt every four months for the life of this machine. Please help and thank you and Exmark for your efforts so far.
     
  10. eXmark

    eXmark Manufacturer / Sponsor
    Posts: 4,258

    Dishboy,

    If Fred's working on it with your dealer your in good hands. I can't think of anyone who has more knowledge and is more competant. If anyone can get your unit figured out it's Fred.

    Thanks

    Terry
     

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