yamaha f-115 making oil

pine island fred

Lieutenant Junior Grade
Joined
Dec 20, 2002
Messages
1,144
Hello, been awhile had trouble getting into the new format.
Have an 05 yamaha 115 4 stroke. Did not get to check the oil ( my neglegance) until the motor had 44 hrs. When I did I found the crankcase full right up to the top. Hoped that I was overfilled when the dealer hung the motor. Drained the oil and installed a new filter. Left it 1 qt. low to see what happened. After 10 hrs of operation I now have the dipstick up to the full mark. Somewhere I gained 1 qt. of oil.
Have read the FAQ on this problem but it is definately not water. Cant pick up an oder of gas but figure thats all it can be. Anybody have any ideas of where to look for a problem? Motor is under warranty but I am reluctant to take it to the dealer. thanks, good to be back, FRED
 

JB

Honorary Moderator Emeritus
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Mar 25, 2001
Messages
45,907
Re: yamaha f-115 making oil

That's what warranty is for, Fred.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: yamaha f-115 making oil

I am with JB.
take it in have the cooling system checked and a leak down test performed.
did you follow the breakin procedure to the letter or skip a bit?
what is the WOT RPM?
what is your normal duty cycle when using it ?
if an EFI 4 stroke gets run in an RPM band that is lugging the engine it will make oil rapidly.
 

pine island fred

Lieutenant Junior Grade
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Dec 20, 2002
Messages
1,144
Re: yamaha f-115 making oil

Thankyou for your reply. Believe I did a good job on the breakin. However the WOT which is 5200 was not hit to often. Normal rpm has been restricted to 2800 to 3400 with a running time of 1/2 on average. Have to admit my not checking the oil until 44 hrs. does not say much for my diligence.
One thought, when I put the boat together I elected not to use an anti_siphon valve and installed a shut off valve at the tank instead. Well I have never turned the tank off. Lots of time passes until I use the boat but when I do the primer bulb is always hard and the engine starts in 1 or 2 revolutions. The few occasions when I do add gas the tank is a bit pressurised. Could the fuel sym. be relieving itself in this FL. heat? Just looking for an easy fix.
Warrenties are wonderful things. But my reluctance goes back to new car warrenty experiences in the late 60s and 70s. Guess in the end I will have to take the boat back and see if things have changed. regards fred
 

rodbolt

Supreme Mariner
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Sep 1, 2003
Messages
20,066
Re: yamaha f-115 making oil

your lugging the pee outa that motor. nothing I can say will help.
sorry.
nothing any dealer can do.
reprop it so it can bounce the rev limiter if you wish to use such a low cruise RPM or nothing will help.
its the way EFI works.
at that low an RPM the engine is lugging and cobustion pressures are spiking and blowing unburned mix past the rings.
that motor will be much happier cruising above 4000
 

pine island fred

Lieutenant Junior Grade
Joined
Dec 20, 2002
Messages
1,144
Re: yamaha f-115 making oil

Thanks rodbolt. I WILL take your advice and try that first. Am currintly running a 13 diam. 19 pitch ss. Will jump over to the prop section, get some advice and order a new prop thru iboats. I ment no offence to dealers and warranties, just had to many experiences where nothing was found wrong until the warrenty ran out then suddenly the cars needed repairs at my expense. Never had that problem with a japanese product but I never had to take them back. FRED
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: yamaha f-115 making oil

no worries,but if you think of this as a car motor your in for serious heatbreak.
dude it aint a car motor.
I really dont care what pitch prop your running, your lugging the motor.]
jack it up and get bugs in your teeth
 
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