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3.8 v6 OMC outdrive ????? Oil type, change advice...... very bad noise

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xrdad

New member
My father in law brought over a 1984 boat with OMC and 3.8 v6. We were cruising along, the boat was running like a dream. Cut through an area that we later found out is full of sand bars. In a no wake zone we were barely moving, the motor suddenly felt like it was bogging down, the bucked a little bit. We put it in nuetral, no issues. Back in gear, bucking and slowing, neutral fine, back in great a little bucking then the whole outdrive swung up then back down. We stopped the boat, waited and then headed for the dock (1/4 mile). Everything seemed normal. We pulled out of the water. My fatehr in laws friend said the outdrive is probably low on oil. We drained the upper unit, hardly any oil drained out, and about 1/2 cup of clear water came out. No mixing of the oil and water,

What lind of oil do you put back in? the manual only says OMC outdrive oil.

What would cause the outdrive to buck like that?

No sign of metal in the oil, the manual is not clear on how to fill it back up; it refers to a fluid lock, what the heck is that.

I really need some help here.. Thank you very, very much!:confused:
 
xrdad said:
drained the upper unit, hardly any oil drained out, and about 1/2 cup of clear water came out. No mixing of the oil and water,
What lind of oil do you put back in?
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you'd be wasting oil at this point

xrdad said:
What would cause the outdrive to buck like that?
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a mess of scrap steel that used to be gears

xrdad said:
No sign of metal in the oil,
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oil? you mean water? metal doesn't float around in water like it will in oil. it's all in there.

take the drive off, disassemble and repair upper, 80W90 goes in after that
 
hystat said:
you'd be wasting oil at this point

a mess of scrap steel that used to be gears

oil? you mean water? metal doesn't float around in water like it will in oil. it's all in there.

take the drive off, disassemble and repair upper, 80W90 goes in after that
Click to expand...


Thank you for the input. I was thinking this couldn't be a good situation. After the outdrive 'bucked' it seemed to drive fine, forward and reverse ( as we were docking). Would the be typical binding or knocking with severe gear damage?
 
if the upper gearcase was run under load for more than a minute with no oil and just some water in it, it is irrelevant how it ran, or what the symptoms are, were, or will be.
It is junk. The bearings and the gears are no longer.
That's all I read the first time through. I don't know if bucking or any other symptoms have anything to do with the upper - but it is toast.

Your post reads like a demolition derby report. You tortured the thing by running it through sandbars with no drive oil and what else? no wonder something was bucking.. poor boat.
the drive is supposed to swing up when you hit a sandbar. they don't always, you were lucky. Now the tilt clutch might be slipping allowing it to lift easier than it should. ( an 84 should actually have the external tilt clutch adjusting screw on the end of the clutch shaft where the segment gear is)
I'm not sure you should fix that though, unless purchasing some charts is in your plans.
 
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Don't get me wrong; I do appreciate your input, I'm aware of the relationship with bearings and lube, There was no demolition or torturing going on. At 51 with a fair understanding of the relationship between loads, torque, bearings and lube I can say there was no abusive behavior going on. I'm a novice when it comes to boating and was just trying to offer as much info as possible.
I have also read through research it is normal to only have a couple of teaspoons of oil come out of the drain hole for the upper unit; the rest needs to be vacummed or pumped out; is this correct? I believed there is sufficent lube as the boat was supposedly recently serviced before selling.
I can sincerely appreciate one trying to reason what somebody is trying to communicate and truly do appreciate your feedback. I'm not some drunken yahoo here that decided to put the key in and go for a midnight ride.

I can see by your other threads you are to the point and helpful.

I thank you for your assistance; really!
 
xrdad said:
it is normal to only have a couple of teaspoons of oil come out of the drain hole for the upper unit
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no - you should get almost 2 quarts of oil.
chevelle047.jpg

if water came out and it wasn't milky, (mixed with oil), there was no oil.
 
Actually, the upper gear house only holds 16.6 oz of oil according to the manual. I know that mine takes exactly this amount. It will not seem like a lot. When you removed the drain plug, did you also remove the top dipstick/vent? If not it could be that the slight vacuum is holding in additional oil that's in there. With the top dipstick removed almost all of the oil will drain out so no, it will not need to be vacuumed or pumped out.

Either way, considering the situation you went through and the fact that there was water, I suggest you pull the drive and take apart the upper gear case to see what kind of condition everything is in. Get yourself a manual for this job.
 
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Hystat and Nivekt; Thank you both for your time and input. Very much appreciated. Thank you for the trouble of posted the pics Hystat.

We changed the lubes, ran the situation by what I would call an OMC 'enthusiast'. The boat is old and supposedly had a completely overhauled outdrive. We took the boat for a 4hr cruise at 3200, 26 MPH. Ran flawlessy, stethoscope doesnt reveal any alarming chatter or vibration at all. Drained the oil out of the upper unit; clean, no foam or metal. I think we dodged a bullet.

My passion has always been fast cars and faster bikes, I appreciate your advice.
 
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