Another upper gear case seals question -

[CamaroMan]

Hi all - sorry to ask a seemingly basic question but cant get a good idea from the merc manual on what exactly to do -

Got a kit and helped some1 install new seals - we couldnt exactly figure out what direction they go -

When we took it apart there were 2 seals in the upper drive that we took out from the top - nothing from the bottom.

In the kit were 2 matching seals and also one thicker one that was about 3/4 the thickness of the other 2 combined.

We put in the two matching ones from the kit, one with the lip/spring facing down toward the lower housing, and the 2nd one with the lip/seal facing up toward the upper gear housing.

I used permatex form a gasket #1 (hard setting/fast drying) on the seals and put everything back together. After about an hour and a half in the hot Socal weather I did a low psi test of 2, and then later a 4 psi test and the whole unit held up perfect.

Anyway - I want to know if we made a mistake along the way? Got conflicting info online where one posted said BOTH lips have to face upwards

Saw a video online showing to install one seal from the bottom, or is that possibly for different models? And did we just happen to get an extra seal (thicker one - what models does the thicker one go on?)

thanks

 

[Rick Stephens]

Not being sure of your drive, sounds like a Alpha1 Gen 2. If so, then you installed correctly. You always face the lip, and spring, towards the liquid you are trying to keep in or out. So the bottom one is holding water out and lip/spring is down, the upper one is holding oil in, so lip/spring up.

 

[Bt Doctur]

Never believe anything you see,/read on the web unless it comes from a official manual
Seal Installation
1. Lightly oil the bore with Quicksilver High Performance Gear Lube.
2. Assemble the first seal to the long end of the driver tool with the lip (spring) side facing
away from the driver shoulder and press the seal into the bore.
70705
a
b
c
a - Oil Seal (Lip Down)
b - Drive Tool (91-817570) (Long End)
c - Driver Rod (91-37323)
3. Lightly oil the bore again with Quicksilver High Performance Gear Lube.
4. Assemble the second seal to the short end of the driver tool with the lip (spring) side
facing toward the driver shoulder and press the seal into the bore.
70706 a
b

http://www.boatfix.com/merc/Servmanl/14/14cover.pdf

 

[achris]

Agree with BT. Install one seal facing down the other facing up. That big double lip seal is for the later gen IIs.

Pull it apart, get new seals (because you used a hardening compound the old seals will be damaged on removal) and put them in according to the factory manual.

 

[CamaroMan]

Hi thanks guys - relief! Well I think she will hold up then. The permatex form a gasket #1 datasheet shows a 5000psi strength which is plenty for this application imo.

BT - I dont have all the special tools, I used a large flat washer and a very straight push to drive it in - the sealant works well as a lube before it dries.

Thanks for the replies guys!

 

[Rick Stephens]

I had seen somewhere a Mercruiser page stating you use aircraft sealant on those two seals. I know I'm stepping in it saying that because Manual #14 clearly says use gear lube. But I remember somewhere, and it had to be a Merc manual since I don't follow or even read anything else vis a vis working on sterndrives. Can I find it though - no. Can't imagine it hurting anything, a light coat of sealant on the outside of those seals... at least until you need to take em out :^)