1979 mercry 140, lower unit/gearcase seal kit number

[bikepainter]

Hello, I am have trouble finding a part number for the correct lower unit seal kit for a 1979 mercury 140 outboard, serial number 5552592. I have scoured the internet and the ones I could find cover serial number ranges above and below mine. I resealed last year with a set I assumed to be correct and it held for half a summer last year then water intrusion began at water pump and some slight oil leakage at bearing carrier outer seal near prop. The part number used last year was Mercury 55682A1 SEAL KIT. Any help.locating a proper part number for mercury or Sierra would be appreciated. Thak you for any assistance.

 

[Faztbullet]

Was the drive shaft pitted??

 

[bikepainter]

No, it was in good shape, could barely tell where the seal contacted the shaft. It pressure tested good, after rebuild, held 12 psi for over 48 hrs

 

[racerone]

Looks to be the right kit if lower unit is original to a 79 model.----Did you pressure test after you installed the kit ?-----Pressure test now to find out what is leaking .

 

[bikepainter]

Yes was pressure tested after the rebuild.and reseal and held 12 psi until I removed pressure tester after 48 hrs. Did pressure test the other day, immediately loses pressure from water pump somewhere within 2 seconds and only holds enough psi to make a small hiss when I unscrew pressure tester. I will try to reseal again and check seal contact areas as I go.

 

[Chris1956]

If the bearings have any play, the seals can leak, while in use, but seal when bench tested.

 

[Faztbullet]

That unit should have non preload driveshaft and upside down roller bearing. If bearing had excessive play to cause seal to leak it would have crapped the gears by now. Make sure you use correct seals and facing correct direction.