Front tires kneed in

Just bought a used yammer 2000 diesel with front end loader, the previous owner just replaced both front wheel shafts, hubs, spindles not sure what they are called. But when I unloaded it the front wheels turn inward, left side looking from seat will turn 90 degrees. Did he forget to do something to keep wheels from turning to far. This is my first tractor so it's all Greek to me.

Can't answer specific to Yanmar, but sounds like there could be some linkage out of adjustment.

Try picking the front wheels up, give each one a side to side shake, look for anything loose or worn in the steering linkage. Let the wheels back down to where they just touch on level ground.

Then turn the steering wheel full left, then turn full right, count the turns, then count back to half the number of turns. This will put the steering gear in the center. The front wheels should now be straight ahead. If not, the linkage will need to be adjusted. A simple way to check the alignment is to pull a string off of the rear wheel. Tie the string to the rear of the tractor, centerline of the wheel, long enough to reach forward past the front wheel. Pull it tight where the string just touches the front of the rear wheel, establishing a straight line down the side of the tractor. Then measure off the string to the front and rear of the front wheel. Adjust so the front wheel is parallel to the string. Repeat for the other side.

See if that will get the wheels pointing correctly. There may or may not be stops, but I would think there should be.

could have right spindle on left side.that will trow things off as seems the keyway is in a different location on them little buggers

All vehicles with two steer tires work on what's called the Ackerman principle. In effect, the inside tire must turn sharper than the outer to follow a smaller radius circle. That said, if there is an adjustable drag link between the pitman arm and the steering arm on the spindle, it is highly likely it is misadjusted. Shortening or lengthening a drag link will give a bigger or smaller turning radius.

More information is required.

What do you mean by "turn inward?" Is this something that happens when you turn the steering wheel? Do the wheels just flop inwards?

If they just flop, look to see if the tierods are connected.

If the tierods are connected, turn the steering wheel and watch things as they move. See what doesn't move. That's where your disconnect is.

I removed the front tires and the spindle and found that the key had sheared, I was thinking more inline with a pin. Will try to reassemble tomorrow. Thanks for the responses, keep up the good work.