1998 40ELPTO gear oil from weep hole?

[Shaunisonfire]

Hi all, I'm new to outboard repair so I apologize if I don't get all the lingo correct.

I have a 1998 Mercury 40 ELPTO. Last year I noticed that there seemed to be some gear oil coming out of the "weep hole" in the lower unit ( Pic 1 ) . I took off the lower unit and had a look ( Pic 2 ). I noticed that where the gear oil was coming from is just a "cavity" with no seals ( Pic 3 ). I decided to pressure test it and put 10lbs pressure and it held solid for 15 mins ( Pic 4 ). Looking back at the motor I see there's a channel going up to the "Power head"( Pic 5 ).

Seeing as the pressure test is good and I don't seem to have any leaks. Where could this gear oil have come from? I noticed it after running the motor with a set of rabbit ears in the driveway. Is this something I should worry about?



Any info would be appreciated by this newbie. Thanks!

 

[merc850]

Looks like it could only be water coming from that area, does it smell like a hi-sulfur content liquid like gear lube?

 

[racerone]

Could be the oil that is mixed with the gasoline.------Some fuel mixture goes right through the motor.----It does not get compressed .----It is not burned.----It is wasted and ends up going out with exhaust.

 

[cyclops222]

Some crappy oils WILL form white Cream Cheese on the lower unit bypass openings.

 

[Shaunisonfire]

Could be the oil that is mixed with the gasoline.------Some fuel mixture goes right through the motor.----It does not get compressed .----It is not burned.----It is wasted and ends up going out with exhaust.

Would going with a better oil like ( Quicksilver Direct Injection Engine Oil ) or ( GENUINE MERCURY PREMIUM PLUS 2-CYCLE OUTBOARD OIL ) Be a better choice? I think right now I'm using a ( MotoMaster 2-Cycle Outboard Marine Engine Oil ) Big price difference :S

 

[racerone]

Oil type does not matter.-----Some fuel goes right through the engine !

 

[Dukedog]

leaky seal under tha water pump............. unburnt fuel mixture goes out tha hub with exhaust....... if bad enough it makes tha prop look nasty............
there is only supposed ta be one way for gear oil ta exit tha case and thats tha two drain/fill plugs.. if its leaking anywhere else ya have a bad seal at one or more of these places.. under tha pump, shaft shaft and/or prop shaft............... but with it at tha drain hole its more than likely under tha pump.............

 

[Shaunisonfire]

leaky seal under tha water pump............. unburnt fuel mixture goes out tha hub with exhaust....... if bad enough it makes tha prop look nasty............
there is only supposed ta be one way for gear oil ta exit tha case and thats tha two drain/fill plugs.. if its leaking anywhere else ya have a bad seal at one or more of these places.. under tha pump, shaft shaft and/or prop shaft............... but with it at tha drain hole its more than likely under tha pump.............

Thanks for the comment. I'm just confused as wouldn't my pressure test have dropped if there was a leaky seal? I'm now thinking maybe it wasn't gear oil and was just motor oil that didn't burn up as Racerone mentioned. I had assumed it was gear oil but that could be my mistake.

 

[Dukedog]

its gear oil.. your motor oil is mixed with fuel.. easy ta see... put a match to it... there is absolutely no way for fuel/oil mix to exit except thru exhaust unless there is something major happenin' with tha motor... doubt it would even run... as for tha pressure test.. don't know on this end.. seen some really strange things happen with seals and sealin' surfaces over tha years..... but we're tryin' ta diagnose a problem ona computer, so's there's that!!!... jmo.

good luck....

 

[racerone]

Running slow and cool on a hose makes the oil collect in the exhaust housing.----And drips outta the motor !

 

[Dukedog]

like i said, tha only way out for any fuel/oil burnt or unburnt is thru tha exhaust... it drips out tha bottom of tha gear case and/or prop.. not thru a weep hole/drain......................

 

[racerone]

The man stated that gearcase holds pressure and is not leaking.

 

[dubs283]

like i said, tha only way out for any fuel/oil burnt or unburnt is thru tha exhaust... it drips out tha bottom of tha gear case and/or prop.. not thru a weep hole/drain......................

But the weep hole for the cavity pictured is part of the exhaust system. The idle relief vents are in the midsection directly above the weep hole

Its hard for me to imagine gear oil leaking from the weep hole pictured seeing as how the cavity is so far removed from any location in the gear case that contains gear lube

 

[Dukedog]

seal can sometimes give a false positive.. depends on where it stops in relation to tha sealin' surface if tha flaw if is very minor in either... there is absolutely no way for gear oil ta get to that weep hole.... except thru a seal....

he will get it figured out one way or another.... calf rope...............!

 

[dubs283]

... there is absolutely no way for gear oil ta get to that weep hole.... except thru a seal....

Which seal?

The area is above and aft of all the gear lube seals in the gear case. I've never seen gear lube leak into a cavity located above a seal

 

[Dukedog]

if its not commin' from a seal then where/what is commin' from???
besides, he has not confirmed jus what it is thats drippin'???.. looks like gear oil in tha pic but that don't mean nothin' ona computer..........

other than tha drain/fill holes tha only way in and/or out a gear case is a seal in one or more of three places.... like said, calf rope.. he'll (or someone) will find it.........................

 

[dubs283]

if its not commin' from a seal then where/what is commin' from???

Most likely excess/unburnt oil from the exhaust. To me that's the most pragmatic assessment, ymmv

 

[Dukedog]

thats exactly why he needs ta identify it.... computer pictures jus don't cut it....