Forums
New posts
Search forums
What's new
New posts
New media
New media comments
New profile posts
Latest activity
Media
New media
New comments
Search media
Members
Current visitors
New profile posts
Search profile posts
Log in
Register
What's new
Search
Search
Search titles and first posts only
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Bobcat Skidsteer Forums
General Bobcat Skidsteer Forum
743 put in new ujoints sounds like something in bind. Can the key to the spline an adaptor be worn out
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Help Support SkidSteer Forum:
Message
<blockquote data-quote="Dave1234" data-source="post: 131779" data-attributes="member: 23099"><p>I don't know if this will be helpful, but going back to the start here, we never heard why the original U Joint failed. I suspect no one knows, but it may have had the same underlying problem, in which case a new U joint won't last long. Had the engine been out before the current round of repairs, when some shims under the motor might have been lost, leading to the original u joint being misaligned and consequently failing? If the new U joint as installed on the motor was floppy/flexing freely in both its joints, there is no problem with it, assuming there is no way to install it off center of the flywheel. Can we assume the motor turned over properly prior to installing it? If not, could it have a slightly bent crankshaft or connecting rod causing binding at certain positions? We are all assuming you correctly identified the U Joint as the problem, but I am not sure that is a reliable assumption. If the motor cranks without binding when not connected to the pump, and the U Joint flexes properly, then it seems that the only remaining choices are:</p><p>1. Elevation misalignment between the motor and hyd pump shafts, which the U joint isn't equipped to correct-- it can only fix angular misalignment. That might not be obvious when installing the motor as I expect there is some fighting involved in sliding the u joint onto the pump shaft, and elevation misalignment might not show up until the motor mounting bolts were tightened. Possibly loosening them might eliminate the problem and point toards a solution.</p><p>2. Bent hyd pump shaft--does it turn freely with the motor out?</p><p>3. Hyd pressure build-up when cranking--is the Aux control in the detent position with nothing attached, or are drive controls sticky and hence out of neutral position. It might be worth putting it on blocks if this seems likely so the wheels can turn freely, and double check the aux hyd control positioning.</p><p>4. Liquid in a cylinder. Fuel, or possibly blown head gasket allowing coolant pumping in and out of one cylinder.</p><p></p><p>Sorry but all of these except #3 & 4 require partially removing the motor again. . It would also be very helpful to have a more detailed description than "probably binding".</p></blockquote><p></p>
[QUOTE="Dave1234, post: 131779, member: 23099"] I don't know if this will be helpful, but going back to the start here, we never heard why the original U Joint failed. I suspect no one knows, but it may have had the same underlying problem, in which case a new U joint won't last long. Had the engine been out before the current round of repairs, when some shims under the motor might have been lost, leading to the original u joint being misaligned and consequently failing? If the new U joint as installed on the motor was floppy/flexing freely in both its joints, there is no problem with it, assuming there is no way to install it off center of the flywheel. Can we assume the motor turned over properly prior to installing it? If not, could it have a slightly bent crankshaft or connecting rod causing binding at certain positions? We are all assuming you correctly identified the U Joint as the problem, but I am not sure that is a reliable assumption. If the motor cranks without binding when not connected to the pump, and the U Joint flexes properly, then it seems that the only remaining choices are: 1. Elevation misalignment between the motor and hyd pump shafts, which the U joint isn't equipped to correct-- it can only fix angular misalignment. That might not be obvious when installing the motor as I expect there is some fighting involved in sliding the u joint onto the pump shaft, and elevation misalignment might not show up until the motor mounting bolts were tightened. Possibly loosening them might eliminate the problem and point toards a solution. 2. Bent hyd pump shaft--does it turn freely with the motor out? 3. Hyd pressure build-up when cranking--is the Aux control in the detent position with nothing attached, or are drive controls sticky and hence out of neutral position. It might be worth putting it on blocks if this seems likely so the wheels can turn freely, and double check the aux hyd control positioning. 4. Liquid in a cylinder. Fuel, or possibly blown head gasket allowing coolant pumping in and out of one cylinder. Sorry but all of these except #3 & 4 require partially removing the motor again. . It would also be very helpful to have a more detailed description than "probably binding". [/QUOTE]
Verification
Post reply
Forums
Bobcat Skidsteer Forums
General Bobcat Skidsteer Forum
743 put in new ujoints sounds like something in bind. Can the key to the spline an adaptor be worn out
Top