Nasty Oil........

[SamiGuy]

Here's one for ya! As I purchased this F115 Yamaha from a "original owner", the engine was "serviced" right before I got it. Oil on the dip stick would indicate the same.... BUT, after running this sucker for about 4-5 hours, the dipstick oil is a bit, shall we say, nasty. Looks like the oil from my SUV at regular oil changes. Methinks that MAYBE, the engine was serviced by either a "suck and pour" method, or was changed when it was cold, not getting everything out and probably left a lot of crap in the pan. The engine has less than 200 hours on it....I'm sure it wasn't maintained like I would do it by the condition of several other items.
So in my world, think I'm gonna do a change myself so I know what's going in. And probably get some of the gunk that is stirred up out with a "warm" change.
Now my question is, will the motor get warm enough on muffs? I'm guessing it might, or I could drain the sucker after pulling it in. But again, that would be after and "idle in" of about 1/2 mile. All opinions are appreciated!!!
Thanks,
Sami

[teecro]

And what is your opinion of nasty?

[SamiGuy]

Good question! Looks like the oil I pull out of my SUV after about 5000 miles at oil change. Not like the fresh, clean oil that is usually on a dipstick after an oil change. That make sense? Not diluted or milky, just not what I would expect from oil after 4-5 hours of runtime. Appreciate your input !
Sami

[teecro]

Good question! Looks like the oil I pull out of my SUV after about 5000 miles at oil change. Not like the fresh, clean oil that is usually on a dipstick after an oil change. That make sense? Not diluted or milky, just not what I would expect from oil after 4-5 hours of runtime. Appreciate your input !
Sami

Oil color is very subjective indeed... But after 4 to 5 hours I would no longer expect it to look new as a change in color indicates that the detergents are doing their job and picking up and holding contaminates.

[SamiGuy]

Been around four stroke engines most of my 64 years and have serviced my fair share....and more. I have never seen oil come out of an engine that dark/dirty in such a short time. My question and plan are proposed for assistance in my call and HOW to best change the oil. It is in my subjective opinion that the engine is not as clean as it should be with normal/usual maintaince. If I am wrong, please straighten my out. Otherwise, I ask, will a running on a muff warm the engine enough to get a warm and fully circulated for an oil dump. I sincerely appreciate any and all help.
Thanks,
Sami

[C_M_25]

Yes, running the motor on muffs is fine. I did it and I have nearly the same motor as you. In fact, that's the general procedure at our dealership.

[teecro]

Yes running the engine on the muffs will indeed get the oil hot enough to improve the drain as all you really need to do is warm the oil and circulate it so that it may pick up and hold any contaminates in suspension. Is there a proper oil drain on your engine? If so by all means use it as it is possible that the last oil change was not done properly. Truthfully for the meager cost a new oil filter and oil of your choice is a small price to pay for your own knowledge.

[joe20toon]

I'm not sure what happened here. Before you ran the engine, did you check the oil level?
Were you able to see a difference "before and after" ?

Also, yes you will get the engine warm enough on muffs for the oil change.

If I bought a used engine, the first I'd thing to do would be new oil and a new filter - as well as a new washer for the drain screw.
I'm not too trusting of strangers telling me what they may or may not have done...

[Bamaman]

I'm a believer that anyone buying a used boat should perform routine maintenance immediately--even if it's not required. I'd change the oil and filter, lower unit grease and gas filter(s) if applicable. I would also disassemble the axle hubs, clean and inspect the bearings and regrease them with heavy, sticky axle grease.

You just don't want any surprises.

I prefer to use Mobil 1 EP full synthetic oil in my Yamaha outboard. I went on Fram.com and figured out that Yamaha's oil filter for my F150 is actually the same as those used on the Ford Focus 2.0 engine--and can be bought anywhere reasonably.

[SamiGuy]

UPDATE: I did change oil, filter, and lower unit. Fuel filter/separator. Now after about 30 hours, the oil looks much cleaner than before. If a service was done right before I got it, there must have been a lot of junk in the crankcase and/or the change was not done correctly. Great advice on doing another change. Thanks!!!
Sami