Ok, looking for some help here before sending oil sample off to Blackstone Labs.

Just did an oil change on my Merc 377's whippled (290hrs), when I pulled the oil filter on each engine, oil was jelly-like in both. First time the oil has ever been like this after an oil change.

Oil is Quicksilver 25w-40; had about 30 hrs on it for the season, about 12 months old and I did NOT run the engines before pumping the oil out. Oil didn't smell burned and wasn't discolored as if it had water in it. Been using the same oil and filters for a few seasons now on this boat. It was also 75 degrees out (sorry to all my northern brethren), so the cold isn't a factor here.

My only thoughts were that maybe it was burned (but didn't smell) or possibly got fuel in it. I'm at a loss otherwise, what else would cause the oil to turn to jelly? Thoughts?

Thanks in advance.

- Tim

Tim, this is a very interesting question - and I really am looking forward to everyone's input.

I'm not a mechanic but in all the years that I have changed oil in cars, truck, and boats I have never experienced that situation. This is definitely a question for Click And Clack - Stump the Chump !!

I doubt if you burned the oil or have fuel in it. I have seen burned oil and it wasn't gelled. Also, I have seen youtube video's of people that haven't changed oil in years/miles on cars and it is more grease than oil - but from your input that isn't an option. Fuel in the oil would dilute it and for sure lower the viscosity. Another possibility - again very remote - with the 25W - your temperature was 75 but the engines could have been a lot cooler and you are just seeing a high viscosity cold oil.

Do you have any "extra" bottles of this oil that would be laying around that you might have purchased at the same time? If you do it would be interesting if you could open and see if they likewise look gelled. I know this is a far fetched question - but you didn't record what lot or batch might have been printed on the oil container did you? If on the VERY slim chance you have an additional bottle you might get the lot number and call Mercury and inquire - if there have been any other complaints regarding oil gelling??

I'm very happy that you are sending this oil out for analysis -

Please keep us posted - this is very interesting

3pointstar

oh ps I'm happy you are someplace warm - Today I'm in Northern Illinois and it is supposed to get down in the low teens tonight !-- No day to leave the Brass Monkey Out !

3pointstar -

I actually had an extra quart of the same oil, used it this go around, but still have the old bottle. Oil wasn't jelled at all in the bottle, but could be worth contacting Merc though. Was planning on running the boat tomorrow with the new oil and filters and checking the filters again. Most likely going to replace filters, a few extra $$$ to be overly cautious.

PS. I'm from northern IL, grew up in Fox Lake on the Chain. Sounds like a great night for a snowmobile ride. Would love to get back up to the midwest again, but current job keeps us on the coast.

MullenTJ86 - that is exactly where I'm at - I stopped by Gordy's yesterday at Fox Lake and talked a little trash. We have a Cobalt 226. I live in Northern Indiana so I'm used to the cool weather.

thanks for the message

3pointstar