1996 Evinrude 88 - Drive Shaft Seal Should never leak under pressure / vacuum - right?

[SeaBisket]

Had milky gearcase oil. Doing a lower unit pressure / vacuum test per the book and the driveshaft seal leaks if I wiggle the shaft around. It will seal and hold solid "in a straight position".

This thing should NOT leak at all, regardless of deflecting the drive shaft, right?

Just looking for a sanity check. I changed it 4 yrs ago and I cannot imagine that I would have let it pass if it "leaked at all".

Thanks!

 

[Crosbyman]

well I think you have the answer .. it is leaking

the question now is ... did the shaft wear down the seal or did the seal just wear down. In any event you have 2 options

repair or change oil a few times in the boating seasons

make certain the oil screw nylon washers are new every time to open them up. maybe they are leaking also

 

[Chris1956]

A lot of those motors have a 2 piece driveshaft. The upper piece moves, simulating a leak in the seal, when the gearcase is off, but not when the gearcase is installed.

Use a bicycle pump to pressurize the gearcase with just a few PSI. The leaking seal will be obvious. keep the driveshaft straight.

 

[racerone]

??---The 2 piece driveshaft leaks.----But the crank holds it in position and then it does not leak.-----And 25 year old motors with some hrs on them will show wear on the seals and it is best to install a kit.

 

[SeaBisket]

Heya all - Thanks for the replies. I attached a video showing how moving the driveshaft releases pressure.

View attachment PXL_20210901_173843412.mp4

The question is, is that normal? It held 15 psi for 24 hrs, if I didn't move it. I didn't remember how this was when I replaced that seal a few years back, but I have to think that it didn't leak "no matter what". I just want to make sure I am not chasing ghosts.. Thanks!

 

[racerone]

Normal for it to leak with what is shown in the video.---That movement does not happen when lower unit is installed.

 

[Crosbyman]

Ha the question remains.... how the the oil get milky ?

 

[racerone]

Was a complete kit installed 4 years ago?----If not , then a complete kit as per post #4 is a must do.

 

[SeaBisket]

Was a complete kit installed 4 years ago?----If not , then a complete kit as per post #4 is a must do.

No. I did the two leaking seals. Drive shaft and shift shaft.

I can do the full deal, though. The gear case one, behind the prop carrier is no fun, but it is what it is.

I didn't replace the nylon washers for the drain plugs this season. This was the first ever instance of water in the gearcase, ironically.

I did finally get that aviation gasket sealer, so anything I do will be better this time.

 

[SeaBisket]

Also, I stopped testing when it failed the pressure test. Knowing now about the shaft wiggle thing, I will now try the vacuum test and check results.

For the 6 and 15 psi tests, I did turn the drive and prop shafts. I also actuated the shift shaft. During these, no leaks presented and it held.

 

[pointblank1000]

Is the drive shaft PITTED right at the seal?

 

[Chris1956]

That looks to me like the driveshaft bearing might be bad. I would pull the carrier off and replace it and the seal and the oring.

 

[racerone]

Nope.----That is totally normal for the models with the 2 piece driveshaft !

 

[Faztbullet]

Racer 100% correct. Unit needs to be a fixture or clamped in a vice upright and level to test correctly...