dirty crud in down leg oil

[intrepid]

Hi I have a 3.0 liter 4 cyliner merc circa 1995<br /><br /> As usuall for the winter I changed my outdrive down leg oil. I put in the Merc high performance stuff like previous years.<br /><br /> But in that little bottle that measures the oil I noticed a concentration of dirty heavy dark green ish blue gooooy crud. I had seen this last year but had not thought about it.<br /><br />I took a clean rag and cleaned most of it out of the bottle. Then I remebered that the lowest plug in the down drive, had been coated in this stuff allso. There was no leak, no metal particles (yahoo) and no water.<br /><br />Is this crud normal ?<br />, and do I have to worry about getting it out of the down leg ?<br /><br />or can I ignore it ? (it hasn't gone away so far)<br /><br />I do about 40 hours a year on the motor & drive<br /><br />Thanks again !!!

 

[Don S]

Re: dirty crud in down leg oil

The sludge in the bottle is normal after a few years, we always remove and clean them with solvent and put new in during winterization.<br />Changing the gear lube every 100 hours or once a year should be fine to keep the drive clean. there will usually be a bit of black goo on the end of the magnet in the drain plug. that's normal. No reason to dissassemble the lower unit. Besides that, without the special tools you can't get it appart.

 

[rodbolt]

Re: dirty crud in down leg oil

what Dons says. <br />its normal. its the additives falling out of solution. see the post on oil shelf life. clean the remote resevoir at every oil change. to clean it you really need to remove it and make sure the nipple is clear.