lower crankshaft seal?

[rustybeater]

OK, I feel like have been on here to much lately but am still having issues with my 1993 Johnson 90hp cross-flow motor. In the first pic you can see that after my rebuild i noticed I was leaking some fuel/oil from the front side of the outboard. At the same time I am also having an issue with the starboard head running about 30 degrees hotter than port. I decided to go ahead and replace the poppet valve and springs and with the bubble back exhaust and with the oil leak i just figure I would go ahead and pull the motor again. Once I pulled the motor you can see that the oil is coming from the lower crankshaft gasket. Now I noticed that there is a little weep hole in this seal. Now my question is: is this normal? should I go ahead and pull it all and replace the seals? Could it be because I have only ran it at idle and have an excess of un-burned fuel or something? thanks for any help.

 

[emdsapmgr]

Probably two unrelated problems. During any overhaul, both thermostats should be replaced, along with the impeller. No point in overheating a new powerhead. So, do both stats and be sure the oval hole in the thermostat valve body is open. If it's clogged with debris, the engine will overheat. Your leaking powerhead could be something else. Perhaps a leaky powerhead base gasket. I've seen two types of OMC base gaskets, a paper one and a paper one with an aluminum coating on both sides. The paper one will fail after just a short time. When that happens, exhaust tar, unburned fuel and exhaust smoke will leak out from under the powerhead. That's a messy situation,but the exhaust leak will fill the cowling while running and that smoke will get re-ingested into the carb intakes. That's the bigger problem. What type base gasket got installed after the rebuild?

 

[rustybeater]

No Title

yes, I replaced both thermostats and the impeller when I rebuild the motor but, one side is running hotter than the other so I decided to replace the poppet valve and the springs inside the thermostat housing. As far as the power head gasket it has just the little paper seal. The thing is though that the front of the outboard (where the oil is leaking) is open. That is where the steering arm comes out of the outboard. So the oil is puddling up in there and running down the front of the outboard. In the Pic this time I circled the wet part. I don't remember this being wet before but, I am not sure because there is a weep hole there in the bottom right where the wet spot is.

 

[AEROCOOK]

In regard to 1 head being hotter than the other, it could be a missing / displaced water defector.
Part number 322411 - item number 10 in the diagram.
You mentioned a bubble back exhaust, was this an upgrade? I thought the 90s were flat backs?

 

[rustybeater]

When I rebuilt the motor I replaced all of the water defectors. I am hoping that the new springs and poppet valve will fix it. I have pretty much gone over the entire cooling system. About the bubble back yes, it is an upgrade. A buddy had one so we threw it on there during the rebuild. We also took all the pistons 20 over and I took the jets in the carbs up a size. Now I just need to figure out if i have to split the case back open to check this lower crank case seal.