How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dan Your Own Question
Dan, Technician
Category: Construction and Road Equipment
Satisfied Customers: 5120
Experience:  17+ yrs. shop and field experience with all major brands of heavy equipment and trucks - 1995 WyoTech graduate.
Type Your Construction and Road Equipment Question Here...
Dan is online now
A new question is answered every 9 seconds

I have a Yanmar B30 excavator. It is quite old. It is

Customer Question

I have a Yanmar B30 excavator. It is quite old. It is diesel, but all of the operating instruction plaques are in Japanese! The operating hours meter shows 3024, but who knows how many times it has rolled over. My problem is that the left metal track keeps coming off. The tensioners on both sides seem to be at maximum deploy. And they are mechanical, not hydraulic. They are at the front, and are adjusted with a wrench. In looking over what pictures I can find on the net, it appears there may be a spring involved as well. I think this machine is early 90's or earlier and I cannot find a manual for one that early. I can get the track back on, but it keeps coming off. Can you give me any advice or info on this?
Submitted: 9 months ago.
Category: Construction and Road Equipment
Expert:  Dan replied 9 months ago.

Hi Paul, My name is***** will be glad to try to help. Usually when the adjusters are extended all the way out and the tracks still come off it is due to worn rollers, idlers, sprockets, and track chains. Check for play in the track chains( pins and bushings), idlers and sprockets/rollers for excessive wear. In some cases you can remove a link to buy more time before replacing the undercarrage as well as turn the bushings on the track chain which is done at a track shop. Let me know

Related Construction and Road Equipment Questions