Originally Posted by George7941
Will do. The reason replacing the seals is my last resort is that I am not expecting sourcing the seals to be easy. The jacks are old inexpensive Chinese made ones.
Seals (lip), o-rings, bearings (I know, not applicable here) are very standardized and a company that designs/produces jacks, pumps, engines, etc will rarely be in the business of making those other parts. Because of this, they source them from other companies. In a previous life, I designed pumps and when we created a shaft, we didn't randomly pick diameters where a bearing would be located or where a lip seal would be needed. We looked up SKF or Parker engineering data for the diameters and +/- tolerances to use existing, easily available bearings or lip seals.
Point is, take the seals or o-rings that you remove from the jack and match them up with off-the-shelf parts. Remember that the I.D. may be stretched on your 'old' o-ring so you'll probably go slightly smaller. Plus, o-rings do stretch anyway. The diameter or cross-section may be swollen too.