Strange leak from prop

[sixdeep]

I have a '93 Johnson v4.
I recently changed the water pump impeller, housing and some gaskets. motor ran fine and tell tail was all working. had a guy check it out who recommended i do the headgaskets. Just finished those, replaced the water deflectors and the exhaust housing gasket. Motor ran fine on the muffs when i tested it, however i just noticed that after leaving the motor tilted down for a while there is this leak of oil out the prop. The only think i can think that it could be is gearbox oil?

Any thoughts on what it is or how to check what's leaking ?

Have attached a pic. This forum has been great so far hopefully someone can help me out here

 

[ondarvr]

Re: Strange leak from prop

It's very common for unburned oil and gas to drain out of the prop, especially when you run it on muffs. Smell it, if it smells like gas and/or normal oil, then that's what it is, if it smells terrible then its gear oil from the lower unit.

 

[Bamaman1]

Re: Strange leak from prop

You probably have bad seals on your lower unit behind your propeller. You're looking at lower unit grease Note: You also have seals on top of the lower unit.

Everyone needs to replace their lower unit grease yearly, looking for signs of water intrusion. Every 3-4 years, lower units need to be vacuum and pressure tested to make sure the seals are good. This is not a place to cut corners.

I didn't properly maintain my 1985 Yamaha 115 hp outboard , and my lower unit simply wore out. Had my problem just been seals, an $85 seal kit and 2 1/2 hours labor would fix it--$300 repair. A new lower unit for my motor is $2500 MSRP--$2100 online. My motor's not worth that investment.

You should never buy a lower unit online or off the street. Only a used lower unit that's been carefully inspected by a qualified marine mechanic should be considered.

Good luck. Your lower unit looks like it's off a "vintage motor."

 

[boobie]

Re: Strange leak from prop

Agree with Ondavr + 1.............

 

[nwcove]

Re: Strange leak from prop

Agree with Ondavr + 1.............

..+2

 

[sixdeep]

Re: Strange leak from prop

Thanks guys, that's a thought i had in the back of my mind but i'm pretty new to boat motors. It doesn't stink like gearbox oil, has the feel of normal engine oil but it doesnt really smell like gas. I thought it may be gas/oil mixed with carbon from the exhaust.

 

[sixdeep]

Re: Strange leak from prop

Got the boat in the water over xmas with my dad and after some issues it ran relatively well, no sign of that leak since

 

[JRDIII]

Re: Strange leak from prop

I'm glad to hear it doesn't appear to be gear oil. But, as Bamaman1 said, leaking seals are not something to mess around with. An air pressure test is a very simple procedure and would be well worth it in a case like yours. You can do it with a bicycle pump and I'm sure there are plenty of instructional posts on this forum. At the very least, drain your lower unit oil and see if there's any water in there. If it's fine, it will cost you $8 or so to fill it back up with oil and you'll have peace of mind. And if it's not fine, you'll be very grateful that you now have the opportunity to replace a leaking seal, instead of replacing an entire lower unit.

 

[tazrig]

Re: Strange leak from prop

Good advice from JRDIII. Preventative maintenance is very cheap. Replacing components is not.