Sundstrand Hydro seal

[MikeES]

Has anyone replaced the input shaft seal on a Sundstrand Hydro (7117) externally? Or does the whole unit need to come apart? This is the shaft that the drive belt is connect to. Thanks for any ideas. Mike.

[bigdog46]

Yes, I have replaced the seal externally. The biggest problem that I had was removing the pulley. The pulley is stamped from sheet metal and welded together. When I put a puller on it, all it wanted to do was bend. But perseverence paid off and I got it off. Replacing the seal was easy then.

[BrianP]

I haven't replaced the seal yet, but will need to shortly. I agree with bigdog, the pulley removal's the hardest part. Use the three P's: Penetrant, Patience and Puller. I had a real problem with the patience part and destroyed the pulley. Thankfully I had a spare. I do reccommend either a harmonic balancer puller or steering wheel puller. That way you're pulling closer to the shaft and not on the outer rim of the pulley. I posted some pics of my adventures in this forum under "7016 Lives again". I was swapping out the whole hydro and that pulley was the only real hurdle I had to overcome.

[MikeES]

Thank you. A friend of mine has this problem and He hadn't taken the pulley off yet and did not know if the seal would come off externally. I will pass on the pulley weakness and let him know it is possible.