Milky oil atop water pump

MassillonBuckeye

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And a little on the drive shaft/slinger seal.. I just re-lubed the LU and changed the impeller last week. When I took off the LU a little water poured out then I saw the milky stuff. Drained the LU lube and it wasn't milky at all. Dark. Which surprised me a bit since I just put brand new oil in it last week. What prompted me to check LU/Waterpump was I ran it in a bucket in garage to test carb mods and noticed some oil on the water. Dark like what was in the LU. Not a whole lot of oil in the bucket but enough for me to notice.

Also noticed a bit of oil on the port side of the LU just under where it mates to upper unit
 

sxmerc

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Re: Milky oil atop water pump

Sounds like the driveshaft seals are leaking. You probably did not run the motor long enough to get intrusion INTO the gearcase. Usually once the gear case gets warm, then it will start pulling in the cooler water. My two cents.
 

MassillonBuckeye

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Re: Milky oil atop water pump

is that under the waterpump? I couldn't get the base off when I did the impeller. pryed at both ends a bit but it would only come up about 1/8" if that. So I just tapped back into place. Ahh yeah I see it there. Hmm might have ruined the water pump bottom gasket as well. Shouldn't have by just pulling it up a hair.. ?
 

sxmerc

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Re: Milky oil atop water pump

Yes sir. Seals are in that housing. Unfortunately that base has to come up for seal replacement. Just keep working at it slowly and it will come.
 

MassillonBuckeye

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Re: Milky oil atop water pump

Yes sir. Seals are in that housing. Unfortunately that base has to come up for seal replacement. Just keep working at it slowly and it will come.

Any other tips if its stuck? Screwdriver used to pry is digging into the plastic a bit. Trying not to gouge real bad.
 

j_martin

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Re: Milky oil atop water pump

Oily sludge on top of the water pump would be exhaust getting into the drive shaft side of the LU because the bead of silicone on the divider was omitted.

hope it helps
john
 

MassillonBuckeye

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Re: Milky oil atop water pump

Oily sludge on top of the water pump would be exhaust getting into the drive shaft side of the LU because the bead of silicone on the divider was omitted.

hope it helps
john

Which divider exactly? I have silicone. And it was less oily sludge than milky grease. Thank you for the reply.
 

j_martin

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Re: Milky oil atop water pump

Which divider exactly? I have silicone. And it was less oily sludge than milky grease. Thank you for the reply.

Gear lube has a distinct odor. If it doesn't stink like that, it's half burned engine oil.

Looking at the top of the LU, the exhaust goes down the aft part, and the drive shaft goes down the forward part. There's a divider plate between them, and the book says to put a bead of silicone along the top of that plate.

On my XR4, I Put a good bead of Permatex blue on it, and let is set till it started to skin. Then I put a very thin film of grease on the mating surface on the mid and assembled. Now I have a reusable gasket in place.

hope it helps
John
 

MassillonBuckeye

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Re: Milky oil atop water pump

Gear lube has a distinct odor. If it doesn't stink like that, it's half burned engine oil.

Looking at the top of the LU, the exhaust goes down the aft part, and the drive shaft goes down the forward part. There's a divider plate between them, and the book says to put a bead of silicone along the top of that plate.

On my XR4, I Put a good bead of Permatex blue on it, and let is set till it started to skin. Then I put a very thin film of grease on the mating surface on the mid and assembled. Now I have a reusable gasket in place.

hope it helps
John

Good stuff! She ran like a champ tonight. WOT no surging, got on a plane real easy. Almost had a rooster tail! Cleaning the carb and putting my battery in the front helped as well I believe. But the motor ran flawless. Will open up LU again tomorrow night and take a look. Any tricks to getting the water pump base off if it sticks? Going to take some sandpaper to the drive shaft and get the bit of rust at the water pump.
 

Chris1956

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Re: Milky oil atop water pump

If the oil is not gear oil, there is no reason to pull the waterpump base, as the seals are intact. If you need to pull the pump base, sand the driveshaft to remove all rust, roughness, etc and then oil it up.

BTW - It is fine for some engine oil to get on the driveshaft, waterpump etc. There is a seal around the exhaust tuner, but it is not too good.
 

MassillonBuckeye

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Re: Milky oil atop water pump

If the oil is not gear oil, there is no reason to pull the waterpump base, as the seals are intact. If you need to pull the pump base, sand the driveshaft to remove all rust, roughness, etc and then oil it up.

BTW - It is fine for some engine oil to get on the driveshaft, waterpump etc. There is a seal around the exhaust tuner, but it is not too good.

How would I know? It was a darker color on the water. But the LU oil when I drained it again was considerably darker than when I put it in(light brown). So thats why it seemed to be the source. There was also a decent amount present which would also indicate gear oil since it wasn't running long enough for that much exhaust to build up... I had only run with MAYBE an hour max that night between several stop and go's. Exhaust oils would have been more of a light coat I would imagine.
 

j_martin

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Re: Milky oil atop water pump

How would I know? It was a darker color on the water. But the LU oil when I drained it again was considerably darker than when I put it in(light brown). So thats why it seemed to be the source. There was also a decent amount present which would also indicate gear oil since it wasn't running long enough for that much exhaust to build up... I had only run with MAYBE an hour max that night between several stop and go's. Exhaust oils would have been more of a light coat I would imagine.

Like I said, gear oil has a distinctive smell to it. It ain't rocket science. Smell the unknown greasy substance, then smell some new gear oil.

motor oil can accumulate to the point of plugging up the whole exhaust system.

Besides, if gear oil were escaping from under the water pump, it wouldn't accumulate on top of it.
 

Mi duckdown

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Re: Milky oil atop water pump

If the lower end lube was not milky than the lower end is fine.
 

MassillonBuckeye

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Re: Milky oil atop water pump

Like I said, gear oil has a distinctive smell to it.
Besides, if gear oil were escaping from under the water pump, it wouldn't
accumulate on top of it.

Very true. Hadn't thought about it like that. Hmm... I believe I did mix the gas a tad rich. And the plugs were dirty/wet. Well hopefully its that simple. Will inspect again tonight and post results. Had it on the water last night after cleaning, re-seating, re-lubing LU. Only had about 30min of runtime. Did notice a slight film on the port side of motor on LU. Very slight, but I know I wiped it clean when I put it back together.
 

MassillonBuckeye

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Re: Milky oil atop water pump

picture.php


picture.php



That there is what I'm talking about.
My first outboard and all my dirtbikes were air-cooled so water makes me nervous! Sorry if it seems simple, but this might help another "noob" like myself heh :) Great replies so far! This is a wonderful resource!
 

Mi duckdown

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Re: Milky oil atop water pump

That Drive shaft don't look to good.
It can not be better under the impeller housing.
Martin ( crusty) Opinion.??
Mi Duckdown.
 

MassillonBuckeye

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Re: Milky oil atop water pump

That Drive shaft don't look to good.
It can not be better under the impeller housing.
J martin. Crusty

What would you suggest? remove pump and hand sand it? Any recommendations on sandpaper? Have dremmel, will travel.
 

Mi duckdown

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Re: Milky oil atop water pump

sand paper will not help.
Do you want the truth? And do you have an OEM manual for that motor?
 

Mi duckdown

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Re: Milky oil atop water pump

How attached are you to that motor. Just kidding?
SO there was NO water in the lower unit. Correct?
I've read all the posts.
Never seen a drive shaft that corroded, that was not in salt water.
How is your tell tale flow? and cool?
 
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