Making oil

[fishnpbr]

I have read much on this forum and others about 4 strokes making oil as it's called. I realize they don't actually make oil but it is fuel. I am not mechanically inclined whatsoever but have a slight understanding of fuel getting past the rings and causing higher oil levels. I hope this is not to lengthy but I want to pose a question and give a history on my motor which "makes oil". When my motor was in the break in process and well past the 1st 10 hours of operation, it took three prop changes to get one that would get me to the correct rpm range at wot. Add to that the motor was operating in cold water, Lake St Clair in April. This is the motors 3rd summer of operation. The first year I put 39 hours on the motor. Last year I did not have a diagnostics done and don't know the current total hours of operation on this motor. I will find that out this fall. After 3 years of operation it still makes oil. The amount is less now than the 1st year. When the oil level gets to the top of the cross hatch mark on the dip stick I change the oil. This is expensive. The motor is a 2007 Merc 115 4S. It takes 25W 40 synthetic blend oil. total cost is over $40.00. I told the dealer of this problem the 1st year and their tech said as long as the oil only went so far up the dip stick not to worry about it. I would guess the motor has in the area of 100 hours. I try and run the motor hard after warm up near or at max rpms as i know this gets the motor hot, but running hard is not always possible with lake conditions. My question is is there any thing I can do to help this problem short of some thing drastic like letting a mech work on the motor. It bothers me when I run the motor and know the oil is diluted with gas even if it is just a small amount, that can't be good. Any thoughts or opinions. Sorry this is so long. By the way the motor runs great.

[coondog]

I have a Yammie 250 that was doing the same thing, every time I checked the oil it was way over full. I also had the same concern, with the oil diluted by fuel. The Yammie tech guys acted like it was no big deal, and accused me of trolling with the big mortor. You would be suprised how just beating the crap out of somebody will get you the answers you need."nuff said. After my wife bailed me out, we sat down and discussed the issue at hand. My mortor needed more time at wot. to let the rings seat in a little better, btw. this engine has about 150 hrs. on it, and it just cleared up. If I were you . I'd burn some gas, and let her fly. The yammie tech guy also said that the oil being diluted wasnt hurting the engine. I have trouble beliving that, but I have warranty thru 2013, and if shes going to shell out, it will be long before that. COON DOG

[angler53]

My F150 made oil during its first fifty hours. The dealers head of maintenance told me to fill up the gas tank and go run it all out with the motor all the way down, wide open. Doing this you can expect to give your arm's a workout, too.
I took it to the lake and did just that. I ran it nearly two hours and the oil level remained high so I went back the next day and did the same thing again. The oil level came down. I changed the oil and filter the next day and it has never moved since.

[jkbrink]

My '03 Yammi 115 has right at 1000 hrs on it and it's done it since day one. I tried the extended run @ WOT and it still does it. Mine's a tiller and DOES get it's share of trolling time. What I find that helps is at the end of each day's fishing, take the long way home and run the bejabbers out of it. I'm thinking it warms it up enough evaporate the gas out of the crankcase. I've also (recently) found out that Yamaha has a fix for my motor, they recommend using the stat and plugs for a f90. They run a little hotter than the originals. The pre-'03's need an up dated ECM to complete the up date but the '03's were running the updated module. Since I didn't find out about the update until this summer, I'll wait until shutdown this fall and then make the changes. Now that I think of it, I'm due for water pump PM this fall too. Looks like a good winter project- - -jerr

[big_crappie]

Most of the time the "making oil" on the 4 strokes is a result of improper break in procedure. I just went through an extensive Q&A session with a Yamaha service rep and was told that people that do not follow the proper break in procedure will be prone to the "making oil" situation as time progresses. The engine needs to have even wear established from new to insure the cylinders do not become "glazed". This is seen quite a bit in motors that were "babied" when new instead of broke in and run. We had an F225 we sold last summer that came back this summer with the complaint that it was running rough and the oil was overful. After several tests we found nothing wrong. We prodeded to get tech support involved and came up with a plan. The motor had 120 hours on it in which over 100 were at under 1000 rpm's. there was only .25 hours over 5000 rpm's which we assumed was our own prop testing before it was delivered. The customer stated that he did not want to hurt the motor by running it hard so for the first season he did alot of trolling and ****tail cruising. I informed the customer that the motor needed to be taken out and "run the cobwebs out of it". He did not want to do it for some reason so I volunteered. For the next week I had that boat to the lake several times and ran the snot out of it. After the 3rd trip you could see a noticable improvement and by the end of the week it ran like a Yammie should. He was happy as was I since I got to hit the water alot with someone else paying the fuel bill.

[fishnpbr]

I did follow try to follow breakin procedure but ran into a problem at the point of breakin when I should have been in the upper limit of rpms. I was not getting near the max range of rpm at wot because of prop selection. I do try and run the heck out of the motor when I can. The oil issue has deffinetly lessened since the 1st year. Can the making oil issue stop in time if the boat is run hard or may it always have this issue with out repair? Thanks to all for your thoughts and responses.

[big_crappie]

It should clear up as the proper wear is applied to the cylinders. I am not saying to beat the **** out of it but do not be afraid to push it to the upper limits of performance as you might say from time to time.

[yarcraft91]

Most of this discussion seems to be about larger outboards, but I've had the making oil problem on my 2006 50 horse Merc 4-stroke, too. Motor was broken in by the book, has 174 hours on it, most at 3500-4500 rpm, no trolling. The first 2 summers, the oil level came up quickly to near 1qt high and stayed there all season. Last summer, it only came up to 1/2 qt high. This year, I see the oil level went up about 1/8" over the MAX mark and has stayed there. Apparently, that's how long it took to really seat the rings the way that motor was used.

Now I wonder- if the motor needed 25W-40 semi-synthetic oil when new, was that to deal with known fuel dilution issues or does the motor really need such a high viscosity oil long term? Since the warranty runs into 2011, I'll stick with the 25W-40 for now, but may have a chat with Mercury Customer Service next year. It's worth noting that the qualification tests for NMMA FCW oil "require" that the oil experience fuel dilution during the test cycle, which is run on a factory-new outboard.

[big_crappie]

Most of this discussion seems to be about larger outboards, but I've had the making oil problem on my 2006 50 horse Merc 4-stroke, too. Motor was broken in by the book, has 174 hours on it, most at 3500-4500 rpm, no trolling. The first 2 summers, the oil level came up quickly to near 1qt high and stayed there all season. Last summer, it only came up to 1/2 qt high. This year, I see the oil level went up about 1/8" over the MAX mark and has stayed there. Apparently, that's how long it took to really seat the rings the way that motor was used.

Now I wonder- if the motor needed 25W-40 semi-synthetic oil when new, was that to deal with known fuel dilution issues or does the motor really need such a high viscosity oil long term? Since the warranty runs into 2011, I'll stick with the 25W-40 for now, but may have a chat with Mercury Customer Service next year. It's worth noting that the qualification tests for NMMA FCW oil "require" that the oil experience fuel dilution during the test cycle, which is run on a factory-new outboard.
Maybe in this case the question should be whether or not to stay with synthetic oil at all. Maybe switching to natural will reduce the blow by.

[REW]

Fish,
You made the comment that you could not run the motor at the recommended wide open throttle setting because of improper prop pitch selection.

I assume that by this statement, you are saying that the prop pitch is too large to allow you to get the motor up to its recommended 6000 rpm wide open throttle setting?

Have you resolved the issue. i.e. have you purchased and use a prop that lets you get up to the motors recommended wide open throttle setting.

If, not, you want to get a lighter pitch prop. Otherwise, you are constantly lugging the motor and making your oil issue worse.

As several other posters have suggested - put a prop on the motor that lets the motor wind up to 600 rpm.
Fill the boats gas tank full - take the boat to a big long lake on a flat day and spend the day burning up all the gas in the fuel tank to get about 4-5 hours of 6000 rpm operation on the engine. Of course you want to be doing this on a fresh oil change.

Good luck
REW

[fishnpbr]

Fish,
You made the comment that you could not run the motor at the recommended wide open throttle setting because of improper prop pitch selection.

I assume that by this statement, you are saying that the prop pitch is too large to allow you to get the motor up to its recommended 6000 rpm wide open throttle setting?

Have you resolved the issue. i.e. have you purchased and use a prop that lets you get up to the motors recommended wide open throttle setting.

If, not, you want to get a lighter pitch prop. Otherwise, you are constantly lugging the motor and making your oil issue worse.

As several other posters have suggested - put a prop on the motor that lets the motor wind up to 600 rpm.
Fill the boats gas tank full - take the boat to a big long lake on a flat day and spend the day burning up all the gas in the fuel tank to get about 4-5 hours of 6000 rpm operation on the engine. Of course you want to be doing this on a fresh oil change.

Good luck
REW

REW it did take 3 attempts to get the right pitch prop. Started with a 19 (recommended by dealer/lund) That would only get 4700 rpm at wot. The recommended rpm at wot for my motor is 5800-6400. Went to a 17 and I think I was in the area of 5200-5400 rpm. Finally went to a 15 and now I get 6300 rpm at wot. I have left this prop on as performance seems good. I will run the boat as suggested. I am closest to LSC, that is a pretty big body of water. I'll just have to find a calm day and go in early morning. Thanks to all for your imput.

[Thumpr50]

I have read and heard more discussion on this topic as time goes on have taken more interest in it as I have a 2005 F150 Yamaha which I absolutely love. Have never had a problem with it making oil and I check it pretty religiously. When I bought the motor discussed with my salesman-a very experienced marine person who takes excellent care of his customers and makes it a point to be "in the know" to help-and his comment was that, per the Yamaha factory techs he spoke with, disregard the break-in noted in the owners manual and to "run it like you stole it". As I read and hear of these "making oil" issues I drawing the conclusion that running it as I did per his suggestion properly seated the rings and averted the problem. For what its worth I also use the Yamaha ring free fuel additive religously and am a firm believer in it even though its a little spendy. Just my two cents worth.