Reply To: Uncertainty regarding Sierra Gear Case Seal Kit

[Don]

STEVEN HOLM wrote:

Working on a real nice 1972 Evinrude Fastwin.  Converting from long shaft to short shaft.  Wanted to do a complete job here, putting new seals in place, prop shaft, drive shaft and shift shaft.  Seems clear, of the two seals, using one in the head assembly on the prop shaft makes sense.  Why? two will not fit.  However, why does Sierra have two in the kit?  They appear to be the same part.  Now, to the drive shaft seal question.  Again, two are included in the kit, both seem to be the same part.  Only one is illustrated to be utilized on the Marinengine.com website.  In this case, room for two in the casting beneath the water pump.  Does anyone have answers to these inconsistencies?  There are situations where newer models have an inner and outer seal, they are mounted one on top of the other, each facing in an opposite direction.  Purpose, keep the water from intruding on one end, gear case grease in place on the other.  In these cases the Marine Engine website illustrates that being the case, depending on year and model. I believe, placing one under the water pump, on the drive shaft is the correct route to take.  However, don’t want to have a failed pressure test and take the gear case apart and have to reseal it again.  Thanks for the help!

Yes, Sierra makes some of these seal kits to fit a wider range of engines…  So, there may be extra parts in there you do not need.. Was there any instructions in the new kit?  You must be very careful, sometimes there are slight differences between the two seals, such as different OK, or different ID on the seal lip…  Take your time and compare the seals before assembly…