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Yamaha DT 250 fork tube seal problems !

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Well, more seal problems- the All Balls seals jammed half way into the seats on the fork tubes and had to be removed. I made a male plug the same size as the fork slider and plugged up the bottom end with a threaded thick aluminum washer. this lead out to another washer on the outside bottom end and another nut. this sealed up the bottom end and I poured the fork leg full of water. Then with the fork tube in special jaws on the vise I put the male plug thru the seal and it rested on the water inside the tube. the seal kept the water inside when I hit the top of the special  plug with a hammer.

After a few whacks with a 5 pound mallet, the seal was pushed out from the inside by the hydraulic pressure. There was still some damage to the outside of the seal, but the fork tube did not get any scratches from a wrench or screwdriver this way.  Now I am wondering if I can grind down the seals to a more reasonable diameter.

The fork sliders are 45.999mm on the ID or 1.810" but the seals are .012" oversize or 1.822".  Any ideas?  I know they are supposed to be tight, but the seals are not just rubber. Has any of you guys ever run into this problem before?

You are the only one with this problem since everyone has the right forks. I will try to help. What size are the fork tubes OD. What year DT do you think it is and what part number did you get from all balls.

 PS Most seals have the size on the seal. What ya got.

Edited by lineaway

If those measurements are correct, you won't get them in. They must be the wrong seals. Also the size of them doesn't seam to match a standard size. I would get back to the supplier

It does sound like you have the wrong seals .

I have replaced several over the years and have never needed to use much force

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