"Chocolate milk" for lower gear oil in my 1985 merc 60hp

it looks normal when i put it in... but after only a few minutes of being hooked up to my muffs... i drain the lower gear oil and it looks like chocolate milk... it has to be water getting in right? where could this be coming from

Re: "Chocolate milk" for lower gear oil in my 1985 merc 60hp

mtlionking22 said:

it looks normal when i put it in... but after only a few minutes of being hooked up to my muffs... i drain the lower gear oil and it looks like chocolate milk... where could this be coming from

Click to expand...

Propshaft seals, driveshaft seals (under the water pump), shift shaft seal, bearing carrier 'o' ring or oil and vent plug washers. Could also be a crack in the housing somewhere (although very unlikely).

In order to find the one, you'll need to do a pressure and vacuum test on the box.

Have a look at this thread to get the idea...

http://forums.iboats.com/showthread.php?p=1573303#post1573303

Re: "Chocolate milk" for lower gear oil in my 1985 merc 60hp

thats a helpful link... i'll give that a try... it wasn't taking on water until i put a new water pump in it... im gonna go through the pump again and make sure i didn't pinch a seal or something then run a pressure test... so besides the oil and vent screws (and a crack) it could only get there through under the water pump or the shaft seals right???

Re: "Chocolate milk" for lower gear oil in my 1985 merc 60hp

mtlionking22 said:

thats a helpful link... i'll give that a try... it wasn't taking on water until i put a new water pump in it... im gonna go through the pump again and make sure i didn't pinch a seal or something then run a pressure test... so besides the oil and vent screws (and a crack) it could only get there through under the water pump or the shaft seals right???

Click to expand...

Not realy; beside the fill and vent screws (and a crack), there's 3 shaft coming out of an outboard lower unit: the drive shaft (the one that goes through the water pump) has two seals, the shift shaft one and the prop shaft two, plus the bearing carrier o'ring.

Click on Gear housing - Driveshaft and Gear housing - Prop shaft to look at the related diagrams:

http://www.ishopmarine.com/ishop/js...de=&pCode=&path=MM~&docId=276&docName=MERCURY | 1985 | 60 | 50/60 HP (3 CYLINDER) - 1060525&isForSupStore=true&cCatFilter=MM&eCatSupFldr=supplier-050-025-MM

Are you absolutely positive that this condition doesn't exist before your w/p change? BTW, most of the time people bought the complete costly w/p kit, including the baseplate and housing, when it's really not required...Next time, if there's no damage to the housing, order only the impeller, you'll pay like 15$ instead of 85$.

Did you happened to change the w/p baseplate? If so, there's 2 seals back to back under it for the driveshaft. Did you replace them?

Re: "Chocolate milk" for lower gear oil in my 1985 merc 60hp

mtlionking22 said:

... it wasn't taking on water until i put a new water pump in it...

Click to expand...

That would have been nice to know in the original post!!!

Re: "Chocolate milk" for lower gear oil in my 1985 merc 60hp

I posted on this a couple of days ago. Per my Merc manual if you run your engine and immediately (within reason) drain the oil it will be choc colored due to aeration and turbulence. Letting it sit overnight and then checking for water separation is their suggestion.

Like Achris said in response to my quoting the manual, "put some oil in a teaspoon and hold a match under it". If it spatters and pops, that's water in the oil boilingl and obviously you have a problem. If it doesn't and you get the oil to "smoking temp" then there is no water and you don't have a problem.

Mark