Old and new lower end oil(comparison)

[STEVE IN SOCAL]

Here's the oil that came with it, and the first change oil (after running it in a barrel post ignition rebuild)...the initial oil drain was way low, as well as 'milkshakey'. The first change out was less milky, but settled out after a week.

I've decided to run it a few times and see just how leaky it is before tackling a seal kit project.

 

[jbjennings]

Re: Old and new lower end oil(comparison)

Steve,
If it were me, I'd run that motor wide open for a short trip with fresh oil in the l.u., see if it held gear well with a few throttle twists to put a little bind on the lower unit to feel confident the clutch dog wouldn't slip. Then if I were satisfied it held gear good and I decided I liked the motor, I'd bite the bullet and reseal the lower unit. That's quite a bit of water just running it in the barrel. It needs a reseal. Eventually, the lack of decent lube on the drive shaft bushings will wear it out and let the drive shaft wobble, ruining any driveshaft seal you put in it almost immediately. Resealing it is a pain and I don't like to do it. However, it is doable and well worth it. One of those motors just isn't really nice and you won't like it until you can go for a ride, pull the lower unit and see good clean oil, knowing that the motor is truly reliable and something you can be proud of. I have about 4 motors that need resealing and to be honest, they're junkers to me until the lower unit is as reliable as the powerhead. Getting the motor to run is not nearly as hard as getting that lower unit right! :redface: Don't worry, we can get you through removing the old seals. Installing the new ones and putting it back together is the easy part. Do it right or you'll be doing it again......
JBJ

 

[STEVE IN SOCAL]

Re: Old and new lower end oil(comparison)

JB...I think a lot of what's in the second batch is residual from the first batch. But you're probably right. I'm taking it to the mountain lakes next week (with a few tubes of lube) and see what's really going on. Another school of thought is that they leak, and just change the oil after each trip. We'll see...I'll report back when I return.
BTW, I did remove some plastic (trash bag?) from the seal at the prop shaft when I checked out the prop. Either the plastic was compromising the seal, or it ruined the seal. Can I just change that seal? I did buy the seal kit when I ordered the ignition rebuild kit.

 

[jbjennings]

Re: Old and new lower end oil(comparison)

Steve,
You can just change that seal, however, I find that splitting the lower unit and getting the old oil cleaned out is such a PITA that I like to just change them all and be done with it. Getting that prop shaft seal out is no harder than getting the driveshaft seal out. I'd just do them both. Then, get a 5/16 tap and tap a couple of threads into the shift shaft bushing and pull it out so you can get the shift shaft o-ring seal out and replaced---it's a good spot for a leak, too.
It very well could be that the water was residual. You might have good luck and your lower unit oil might just need changing regularly if the leak isn't that bad. I doubt it, though. Those seals are probably original and they all need replacing.
Just my opinion,
JBJ

 

[STEVE IN SOCAL]

Re: Old and new lower end oil(comparison)

If I get back from trip, and the news is bad, I'll count on you to hold my hand through the seal change

The seal kit I got has what seems like 10 or more seals.

 

[tashasdaddy]

Re: Old and new lower end oil(comparison)

steve please edit and resize your pictures

 

[lindy46]

Re: Old and new lower end oil(comparison)

BTW, I did remove some plastic (trash bag?) from the seal at the prop shaft when I checked out the prop. Either the plastic was compromising the seal, or it ruined the seal. Can I just change that seal? I did buy the seal kit when I ordered the ignition rebuild kit.

If it looked like melted plastic, it is probably actually melted fishline - yup, good chance the prop seal is compromised. You can pick up a pressure tester on ebay and test the lower unit for leaks. Just pump it up to about 10psi and see if the pressure holds, or where it is leaking. Spray a little dish soap on the seals and look for bubbles, and listen for a hiss. Not a big job to change the prop seal and driveshaft seal. The hardest one is the shift rod seal without the proper tool. Oh, and don't forget the little clutch dog pivot screw seal (the little Phillips head screw everyone says not to take out). I've had only that seal gone bad and the L/U oil was pretty milky.

 

[HybridMX6]

Re: Old and new lower end oil(comparison)

I made my own pressure tester out of a bicycle pump with a gauge on it and a lower unit oil change pump from Wal-Mart. Cost me $12 for the bicycle pump and like $10 I think for the lower unit pump, but the LU pump is obviously re-useable for future oil changes, and I needed a bicycle pump anyways for my bicycle, so it really didn't cost me anything. I pressure tested my LU to 10psi and it held it for well over an hour. I left it like that and the next day it had dropped to 0. Did it again, and it held for almost 2 hours. But again, I left it that way and the next day it was back to 0. Not sure if it's the pump leaking out the air or what, but I've heard if it holds 10psi for over an hour then it's good. Guess I won't know until I give her a go.
Just another option for the LU psi tester.