2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

[sstu]

I have a one year old Mercury 25hp Bigfoot four stroke which has started blowing oil out the carbuerator. Then the oil leaks down out the bottom above the lower end. Any ideas?

 

[JB]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

Hmmmm, Grateful. Sounds to me like something's wrong or broke.<br /><br />Take it to your dealer.<br /><br />Good luck.<br /><br />Red sky at night. . .<br />JB

 

[DJ]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

grateful dead,<br /><br />Not good! Either the engine has a tremedous amount of "blow by" or you have the crankcase vent system clogged.<br /><br />You should see a hose going from the valve cover to the base of the carb. Make sure that hose is clear. Also, if the unit has an air filter, make sure it's clean.

 

[DJ]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

grateful,<br /><br />One other thought, have you changed oil recently? If so, did you use the same weight recommended by the engine manufacturer? Was it overfilled?

 

[sstu]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

Yes the oil was changed recently with the same wt as specified in the manual. It is at the dealer now. they had it for a week and it is worse now. they tell me the engine may be over revving and since the oil is full, that it blows out the carb. I asked them how come it hadn't done it for almost a year?<br />They said it was because the oil was filled to the 3 qts....i said, that what it says on the engine and the book; and they were the last ones to drain and fill it. <br />Over revving? too much oil?? It my dealer barking up the wrong tree?

 

[SeaDawg]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

What pitch prop and what size/type boat is the motor on? <br /><br />That will help some of us to guess if you are overreving.<br /><br />I doubt you have a tach on the motor, but if you do, what is max rpms?

 

[Bear]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

Did you check the oil level after the change? There is a difference between completly dry engine, oil AND oil filter change and just oil change. ALWAYS check oil level before starting after oil change.<br /><br />Good luck!<br /><br />/Bear

 

[sstu]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

I added the recommended amount of oil in the crankcase after changing the filter (at the same time) as the oil. Rememeber , the dealer also drained the oil to check the amount.<br />As I stated, the dealer said the engine is over revving.....but how come all of a sudden. It ran fine for 11 months.....then I had them install the electric starter (use to be a pull start). this is when the trouble began. I wonder if the changing of the flywheel had any effect.<br />Now they said its over revving and may change the prop......why all of a sudden?<br />Will this change the engines performance which was fine up to this problem. I never ran at full throttle for more than a few seconds; before backing down on the throttle.<br />Something smells fishy....

 

[sstu]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

Boat just came out of the shop. the dealer said they have noticed a problem with the head gasket after 30 -40 hours. They said they opened up the ports in the gasket (??) or something to that effect.<br />How come they always look to the owner for blame before they will acknowledge a "known" problem?

 

[singerjr]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

Some dealers are more human than others, you know "checks in the mail" and "it's not my department"<br /><br />Glad you got your problem fixed in a relative short period of time and on their dime. Look at some of those folks on that Suzi thread where dealers and reps have fed them a line for 6 months.<br /><br />Maybe they were being honest and just telling you what they "think" it might be, maybe not. We try and "think" what it might be but a dealer really shouldn't.

 

[Newhook]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

I very recently bought the same motor and was curious to see how your problem resolved. How have you found the motor otherwise? I hav'nt tried mine yet, being winter but intend to put it on a Princecraft Starfish, a 16 foot, 73 inch beam alum utility. I have some some apprehension about the weight of the motor.<br /><br />Let me know your thoughts.

 

[sstu]

Re: 2001 Mercury 25 hp Bigfoot( 4stroke) blowing oil

I ran the boat yesterday and mostly it seems fine. It did hesitate for a second when I back off hard on the trottle. No oil leaking out at this time.<br />I run the 25hp on a Klamath (tin boat) 15 ft'r. As I stated, it is a year old. for the first 11 months it ran fine..very low fuel consumption......<br />It is the smallest engine, most people say to put on a 15 aluminum. Im sure it will work fine on your boat, but Ive seen lots of 40hp's on 16's ...and 15's.<br />good luck...and I hope you have a dealer whose reputation means something to him or her.

 

[barryc26]

I have an 2002 25 merc 4 stroke, oil leak from somewhere, was it the head gasket on your engine that solved your problem? Did you ever find out what "opening the ports on the head gasket" meant?

 

[GA_Boater]

I have an 2002 25 merc 4 stroke, oil leak from somewhere, was it the head gasket on your engine that solved your problem? Did you ever find out what "opening the ports on the head gasket" meant?

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