sludge in oil reservoir

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capri_1850SS_lover

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I was changing the stern drive oil today and I noticed that there is a sludge in the bottom of the reservoir.

Is this something that can happen in one season? Should that have been cleaned out by the place that has been doing my winterizing these past four years?

What would be the best way to clean that out? I have disconnected the hose and the level sensor so the unit is out, but what should I use to clean it out? Gas? Suggestions appreciated.
 
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TilliamWe

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Re: sludge in oil reservoir

It "can" happen in one year, yes. But usually not. No one would clean it out during winterization. Gasoline would be a good solvent to use in order to clean it. That's how I cleaned mine. Removed it completely, poured a little gas in it, put the lid on, sloshed it around, and drained it. Then wiped out the bottle, and let it air dry for a day or two.

BTW, this sludge, it's more common when you use Mercruiser's outdrive oil. It's also how guys run their drives out of oil, and don't know it, cause "the bottle was still full".
 
Don S

Don S

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Re: sludge in oil reservoir

That reservoir should be removed, emptied and cleaned out yearly. it's part of changing the drives gear lube.
I sure wouldn't use gas to clean it. Diesel fuel or kerosene works well, and parts cleaning solvents available at most auto parts stores would be a LOT safer and less chance of causing harm to the hose, reservoir or sensor when using gasoline.
 
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joncrisler

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Re: sludge in oil reservoir

Don S said:
That reservoir should be removed, emptied and cleaned out yearly. it's part of changing the drives gear lube.
I sure wouldn't use gas to clean it. Diesel fuel or kerosene works well, and parts cleaning solvents available at most auto parts stores would be a LOT safer and less chance of causing harm to the hose, reservoir or sensor when using gasoline.
Click to expand...

Be carefull in using any solvent to make sure its compatible with the plastic tank. Do NOT use brake cleaner or contact cleaner. Also, many oils have additives like Molybdenum that sometimes settle out of the oil- this might be what you are seeing. If the oil is a dark blue, black or green this could be what you are seeing.
 
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TilliamWe

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Re: sludge in oil reservoir

Don S said:
That reservoir should be removed, emptied and cleaned out yearly. it's part of changing the drives gear lube...
Click to expand...

That sure is nice to hear from a pro, but I don't think very many shops actually do it, Don. They refill the drive, and top off the bottle, because removing it and draining it is "just too hard"!
Ok, maybe gasoline isn't a great choice, but it can be done. I disconnected the hose from mine, so no worries there. And the sensor survived.
 
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capri_1850SS_lover

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Re: sludge in oil reservoir

For what it's worth, the sludge was a greenish-bluish color same as what drained out of the unit.

My hose was glued and hose clamped to the reservoir fitting, so I ended up disconnecting the sensor wires and rotating the reservoir to remove the tank. I noticed that there wasn't anything on the fitting threads like teflon tape, etc. Should there be?

Thanks for the responses and suggestions.
 
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capri_1850SS_lover

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Re: sludge in oil reservoir

One more question since I'm new to this:

Since there was the sludge in the reservoir, do you think I need to flush or clean out out the hose?
 
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Knightgang

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Re: sludge in oil reservoir

capri_1850SS_lover said:
One more question since I'm new to this:

Since there was the sludge in the reservoir, do you think I need to flush or clean out out the hose?
Click to expand...

I would. Might not be totally clogged, but could be partially reducing the flow through it...
 
C

capri_1850SS_lover

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Re: sludge in oil reservoir

Would compressed air work okay for flushing out the hose if I remove the vent plug on the out drive? I have not yet refilled any of the oil in the out drive yet as I am waiting for the reservoir to completely dry out after cleaning it.
 
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