Lower unit leaking from odd place?

[Thaiboxer04]

I just got my 1982 Tower of Power 90hp (just bought used) temporarily mounted to my project boat last night. I haven't drilled any holes to bolt it on the transom yet and was going to do that today. I went out just now and saw that there is a stream of gear oil leaking on the lower unit but from a strange place. Prior to setting it on the boat last night... I had it laying down so I guess that's why I didn't see the leak. Now I am hesitant to drill 6-8 holes in my transom to mount this motor if it could be a serious issue. The holes that are already in the transom line up to a 40hp Johnson i have but was hoping to use the bigger Mercury. Here are a couple pics...motor is positioned with the tilt/trim up so it's at a 45? angle all night that made the fluid run out. Can anyone give me some insight since now I'm not sure if I should even move forward with using this motor? Thanks!

 

[gm280]

Well that looks like the overflow opening and therefore it could just need a new "O" ring or gasket installed. And I see you have a Glasstream HydroBass boat. I use to own one of them myself. It was a really fast hull too... I have a Merc 115 inline six on mine. Check for a gasket for that screw...

 

[Thaiboxer04]

Thanks gm280. There actually is no screw there though. The fill hole is on the opposite side of the lower unit and up a little higher. This is like a 1/4" hole that didn't look threaded but I'm not at home to check right now. At first glance it looks similar to a small water inlet or something.

On a side note... what kind of performance do you think I may get out of this motor on this boat since you're familiar with it? It's a 15ft. The decision was between this 90hp or a 1992 Johnson 40hp I also have. Thanks!

 

[gm280]

I was getting 60's plus MPH on slight rippled water. It would easily run in the mid 50's all day long without any problems. But mine was bought all new as well.

On that oil leak, if that isn't the over flow hole, I would see what it was and how the oil was getting there in the first place. The lower foot section has to be sealed from the rest of the engine or you will have huge issues...

 

[Thaiboxer04]

No Title

Thanks again. I was hoping for 50mph with this motor. Well I just got home and it does not look at all like a threaded hole and it had oil leaking out again after i wiped it earlier. This is the best pic I could get of it up close. I think I have no choice but to pull the lower unit and see what is going on. This will be tough since the motor isnt bolted on yet :-(

 

[Thaiboxer04]

No Title

Ok well the lower unit came off pretty easy which was a plus. Once I opened it I saw that the hole is a weep hole next to the shift rod. There is one on each side of the lower that must weep as an indicator that there is an internal fluid leak. Does anyone know what seal this would be or have a parts diagram showing what is? It must be whatever seal goes around the shifter rod. Thanks to anyone that can help.

 

[Thaiboxer04]

No Title

Ok. I found a few videos on youtube that show how to get the seal replaced but you need a special tool. I'm wondering if i can make a tool out of an old deep well socket? I pulled the impeller to check on it also... it is wasted of course but looks like some of it melted to the inside of the water pump cover. I'm not sure yet how I'm going to get the melted rubber off of here without damaging the housing.

 

[Chris1956]

Not an unusual leak at all. The likely culprit is the driveshaft seal in the waterpump base. So pull the pump cover, pull the impeller, pry out the water pump base. Now inspect the seal area for grooves. If you find them, you may need a speedi-sleeve to repair it, although that would be unusual.

Now use some emery to clean the whole driveshaft. Now oil it down, and install a new waterpump base (with a new seal), base basket and Oring. Obviously grease the Oring. Now install new impeller, wearplate, two gaskets and water pump cover. That should fix it.

 

[Thaiboxer04]

Thanks Chris. I ordered an impeller kit today and need to figure out which seals are leaking. I'm almost positive it is the shift shaft seal.