Lower unit still leaks air

[200090tlry]

Ok just put new driveshaft seal housing and new seals in there. Manual does not show few parts. I put both seals in going in housing the same direction. Used flat part on seal looks like poker chip side (coil spring in first)and tapped both in with with socket,little grease. There was a locking ring that goes on outside housing to hold them in. Old part did not have this and I figured out seals were installed wrong from the big rebuilder in FL(ARG marine INC) The shift seals and housing new as well. When I put air in housing I can hear air woosh like it's comming out water rock screens on outside bottom lower unit. Is this the sound of lower gear case seals? I figured there good because no oil in the area and cant hear air comming out of prop areas. I ordered lower case seal kit and comes with few paper gaskets just where do those go. How many places can air leak out. Update I just sprayed wd40 around gear case housing inside. Didnt see a leak through(pressure tested) that but I did see some corrosion on the aluminum lower unit casing. You can hear air behind gear casing housing. How can I remove this part to investigate. Special tool needed to remove ring in front.

[BaileysBoat]

We can't help you without knowing what you are working on.

HP, model, year, serial number.

[200090tlry]

just like my log in name

year 2000, 90hp tlry model carby. Where is speedo part I see tube runs in lower unit. The water rock guards at bottom housing came appart when I tried to remove philips screw to get better look inside. Hoping maybe it's a plastic part damaged creating the air leak. But your guess is better than mine. Got a question on seals again do I seat both of those all way in housing or should they be closer to top? Think I found leak Update. Im pointing to area that had air comming through hard. Seems the oring is not sealing enough. Can I rtv this sucker down and make sure no air can get past oring? Im thinking this is a place for air to escape should the lower unit get to much pressure and saves seals and stuff. The lower unit housing looks almost like someone tried to weld more aluminum in there maybe corossion got it's way with metal. Is there a sleave I can ram in there? Maybe a thicker oring

[BaileysBoat]

I'm a bit confused. I can only find the driveshaft housing in the picture in the parts list for a 115 HP?.

The two seals are installed with the flat side down. They should be .030" below the top of the casting.

You don't have a leak. The pencil is pointing to the water uptake passage for the water pump. This is open to the plastic intake screens, so normal.

Where are you applying air pressure?

The o ring is sealing the housing to gear case. To test apply 5 psi pressure at the vent plug. Also apply 10" of vacuum and see if it holds.

[rodbolt17]

the picture of your seal carrier is correct.
in he first pic you have the seal in he correct orientation.
both seals go with the lips(springs AWAY from the case.
then a paper gasket then an oring then install the driveshaft seal carrier.
on the 90 you can bottom the seals against the housing.
the 115 DO NOT bottom the seals.
the speedo tube does not intersect the water intake passages, or its not supposed to.

[rodbolt17]

were the pencil is pointing on the second photo is a water drain area.
either the driveshaft seals are leaking,the oring is leaking the paper gasket is missing or your not bolting the housing down when testing.
leakage points on that case,shift shaft seal,shift shaft seal carrier oring.
drive shaft seals,driveshaft housing oring or gasket.
propshaft seals or propshaft carrier oring.
or fill/vent gaskets.

[Tucker]

the picture of your seal carrier is correct.
in he first pic you have the seal in he correct orientation.
both seals go with the lips(springs AWAY from the case.
then a paper gasket then an oring then install the driveshaft seal carrier.
on the 90 you can bottom the seals against the housing.
the 115 DO NOT bottom the seals.
the speedo tube does not intersect the water intake passages, or its not supposed to.

If this is the case, it looks to me the springs and lips facing DOWN (incorrect). Might need new glasses. Thought the lips and springs where suppose to be facing up (towards powerhead). Read about a lot of controversy with this. Yamaha wants to keep water out. Some techs say that is wrong and want to keep oil in and they reverse the seals.

[99yam40]

If this is the case, it looks to me the springs and lips facing DOWN (incorrect). Might need new glasses. Thought the lips and springs where suppose to be facing up (towards powerhead). Read about a lot of controversy with this. Yamaha wants to keep water out. Some techs say that is wrong and want to keep oil in and they reverse the seals.

I believe the pic shows the carrier upside down, it is turned over when installed

[rodbolt17]

99yam40 wins.
but both seal springs face up when the carrier is installed, means they are upside down when you install them.
I have never installed them backwards.
no one has pics or video so thats my story.

[200090tlry]

So I am good sweet ya coils go in first then smack em in with socket

The problem I belive was oring was not pressing hard enough on wall, someone gouged up inside with screw driver. And the fact seals where installed first one in coil first and second coil showing and not driven in housing or clip installed. I just high temp rtv sucker in and used some alum epoxy repair in damaged area sanded and got to where the seals worked. Maybe someone would have tossed out housing but im trying to scrap and save money all seems good now. Just filled housing up with cabelas lower unit oil. Im questioning the rtv I used as there does not seem to be much silicone in it. But at least I got everything back together and found leak source. Both coils once installed mounted on lower unit are towards powerhead fyi it's confusing language. Or you could say poker chip side is where you put socket on and send it home. I did use the paper gasket and it's interesting that the fit is not all way under spot im pointing at with pen. There's some play in that and water for sure could get down to seal and maybe designed that way to help cool first seal? Im also wondering if maybe water froze in between first seal and damaged alum housing in lower unit. No chance of that as I dabed rtv around edge. Maybe that little spot is for water to drain all way out water impeller to protect in Minnesota winters? Manual stated 14.2 pressure but my tool leaked air out quick connection and instead went for vac test mighty vac at 14. I also found speedo hose was discoed and clamped hummm maybe that froze. There is secondary speedo attached to hull. I used 1/4 landscape hose and quick fitting and hooked it back up I dont want water inside hose. Who ever worked on this lower in past should quit working on outboards. Sure is nice boat though im very particular it getting things right. Hey rod if I need to order new lower with gears and stuff installed do you get deal on them.

[200090tlry]

What would be great if SEI made lower for my 90hp!

For $800 smackers id have it in my hands already. $1750 for new yamaha lower is kind of steep.