Force lower unit oil leak/venting???

[VIP FORCE]

I was just about to go boating today and noticed my lower unit has a section covered with what appears to be light oil. It is venting out of a small hole that is above the area of the fill/vent screws. I know the lower unit was refilled last fall and am wondering is this just overflow venting out or do I have a bad internal seal??? I just dont want to put this in the water today if its going to cause problems...
thanks

 

[eurolarva]

Re: Force lower unit oil leak/venting???

Do you tilt your motor when trailering? Does it smell like gas or lower unit oil. Probably just unburned gas oil mix.

 

[john from md]

Re: Force lower unit oil leak/venting???

If it is leaking from the lower, it will be brown thick oil. If it is residual oil mix from your carbs, it will be lighter and smell like gasoline. The lower unit oil smells a little like burnt rubber.

When did you last service your lower? Did you replace the seals or use teflon on the screws?

What kind of engine are we talking about?

Regards,

John

 

[VIP FORCE]

Re: Force lower unit oil leak/venting???

I do keep the engine fully tilted up when trailering and it does seem to only leak after Ive raised and lowered the engine. It is definately a light oil and very thin. I had the lower unit oil replaced last fall but no seals have been recently replaced. The engine is a 89 Mercury Force 150.....

 

[john from md]

Re: Force lower unit oil leak/venting???

It probably is just oil residue from the carbs but I would check the lower anyway. It is easy to do. Put the motor in an uprite position and take the fill and vent plugs out. Squeeze in oil through the fill plug and stop when it comes out the vent plug. Let it drain untill it stops and then put the plugs back in. This way you know your lower is full.

Regards,

John

 

[trophyforce]

Re: Force lower unit oil leak/venting???

i had the same prob. on my 1994 90 . i was just unburned fuel/oil.

 

[Frank Acampora]

Re: Force lower unit oil leak/venting???

Next time you drop your lower unit, look on either side of the water pump. you will see two blind chambers that can not normally drain so the factory drilled two small (about 1/8 inch) holes in them for drainage. Leakage from carbs, unburned oil from exhaust, residue from inside the engine lower cowling, and exhaust residue all can get into these chambers and drip out the weep holes.

If it were lower unit oil, there would be a very distinctive sulphur odor. Sulphur is one of the elements that gives lower unit oil its extreme pressure rating. Smell lower unit oil once and you will never forget it. Completely different from anything else that would come out of the engine.

 

[mrwiggles2]

Re: Force lower unit oil leak/venting???

Good to know this, this light tan colored oil comes out of the vent hole on my 70 hp all the time. I put my motor down when I get home from boating and never leave it in the travel position.

I was really concerned it was LU oil, as they PO told me when I bought it in August that he had overfilled the lower unit. Good to know this is excess carb fuel.

 

[fishinrado]

Re: Force lower unit oil leak/venting???

HEY all, just found this thread and wanted to see if there was any more info from any of the postees. I just put on a used lower unit on my 1979 105 and took it to the lake. after a short spin I had the dreaded white , creamy oil coming from those weap holes. got home and pulled it apart again and was assuming that the housing seal, where the shift rod goes though, was bad as I had water, oil and gas in those chambers. the one on my replaced lower unit seemed to be fine so I switched them out. after sitting all last night i came out to find a lighter (almost white) oil coming down again from one weep hole. I'm hoping it's gas/oil residue as i did have the motor tilted to reinstall but it sure smells like gear oil. I tipped the lower unit up and down and even upside down before i put it back in ( filled it of course with gear oil) and not a drop from any of the seals around the shift rod, fill hoes/vent or lower plug. Is it possible i'm getting some type of pressure crack to expand once i bolt up this used unit? It's fairly beat but I had a heck of a time trying to find a unit on e-bay or craigslist. This came from fla. and has obvious salt water residue.........Thanx for any input.

 

[elkhunter56]

Re: Force lower unit oil leak/venting???

had water in my lower unit got it pressure tested it failed. I caught the water fairly quickley i believe. Am i ok to just reseal the lower unit or should i pay extra for full inspection what are the odds the water did further damage?

 

[john from md]

Re: Force lower unit oil leak/venting???

Did you have oil in the lower or mostly water?

John