durangoroadboss
New member
Hi folks: After draining the lower unit oil and findingvery little oil, I have installed new seals in the lower unit of my 1974 15-hpEvinrude (model 15404G). When I pressured tested the lower unit, it seemed tohold at 15 psi. When I ran the engine the first time after this work, no oilshowed on the surface of the water in the trash can I used. After the enginesat for an hour or so, two or three drops of oil dripped from the propellerhub. I filled the trash can with water again and ran the engine once more.After a few minutes, a lot of emulsified oil was on the surface of the waterand up the sides of the trash can. I shut it down, and drained the trash canagain; there was a substantial amount of emulsified oil around the prop andwhen I removed the propeller, inside the propeller shaft hub/exhaust area.
I pressure tested the lower unit again and starting at 15psi, the unit appears to lose one psi every 15 seconds or so. I held the outboard with the propeller shaftvertical and pressurized the unit to 15 psi. I sprayed soapy water around the propeller hub O ring and the twoback-to-back propeller shaft seals – no bubbles. I pulled the lower unit, clamped the unit ina vice with the drive shaft vertical, and after plugging the weep hole, filedthe cavity around the shift lever with water, pressurized the unit to 15 psi, andwent through reverse, neutral and forward – no bubbles. I filled the area with water around the doubleback-to-back drive shaft seals under the water pump – no bubbles. The lower unit still appears to lose one psi every15 seconds or so, but I can’t tell where it leaks???
Most importantly, when I pulled the lower unit, the exhaust port fromabout half-way down to the hub cavity and the entire exhaust cavity in thelower unit was coated with emulsified water/oil – probably an eighth of an inchthick. It wipes off, but where did thiscome from? This appears to be the sourceof the dripping oil and all of the oil blown out through the hub exhaust.
Help! Thanks.
Richard
I pressure tested the lower unit again and starting at 15psi, the unit appears to lose one psi every 15 seconds or so. I held the outboard with the propeller shaftvertical and pressurized the unit to 15 psi. I sprayed soapy water around the propeller hub O ring and the twoback-to-back propeller shaft seals – no bubbles. I pulled the lower unit, clamped the unit ina vice with the drive shaft vertical, and after plugging the weep hole, filedthe cavity around the shift lever with water, pressurized the unit to 15 psi, andwent through reverse, neutral and forward – no bubbles. I filled the area with water around the doubleback-to-back drive shaft seals under the water pump – no bubbles. The lower unit still appears to lose one psi every15 seconds or so, but I can’t tell where it leaks???
Most importantly, when I pulled the lower unit, the exhaust port fromabout half-way down to the hub cavity and the entire exhaust cavity in thelower unit was coated with emulsified water/oil – probably an eighth of an inchthick. It wipes off, but where did thiscome from? This appears to be the sourceof the dripping oil and all of the oil blown out through the hub exhaust.
Help! Thanks.
Richard