Most seal problems are the shaft is running out of round on bad bearings. The bearing may look good, because of long use are worn. Or not being use very much the bearing and seal dry out. Even if the shaft is in oil there is more weight is on the bottom of the seal. Then when turned its elongated and runs out of round at the start there could be a small leak until the seal is warmed up. Next is a scored shaft or scoring on the shaft cause by seal not turning inside of its self. End play and loose jam nuts allows shaft movement up and down, in and out. It does not take much as most seals do not move more than 1/8 inch and that is a lot.
Water and cold weather freezing is a cause also. The transmission or equipment housing has water or moisture in the oil setting at the seal. This cause rust and the seal will leak. Cold weather with moisture in the oil will freezing on the cold shaft. When it is turned will break the seal loose from the shaft. Causing a leak because the seal is frozen in the inner seal part.
A seal turns inside of its self. Most seals are 3 part, outer ring, inner ring and wire spring. There are other configuration of seals. Seals are made from a number of product for different applications.
When installing a seal that is running in oil. If is not a new shaft and new seal. Use blue or clear silicone on the shaft in the area of the seal. A thin coating under the seal will fill the pitting you can not see without a magnifying glass. This holds the inner ring to the shaft to keep it from turning. Do not use Permatex as it will cause failure in the seal and damage other parts.
There is disagreement among mechanic and different industries in using silicone under the seal. Seal are made to keep the dirt out and the oil in. They are not made to carry the load of the shaft.
PTO SEAL ON 94 600 HO
Re: PTO SEAL ON 94 600 HO
