slight gas in oil 2009 yamaha 4 stroke

stevedan

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Apr 27, 2023
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my thermostat was opening and closing around 125 up to around 140 (checked with inferred gun) Also with currently a 23 pitch prop, what would be a better pitch to have (in your opinion). ??
 

cyclops222

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Honda car engines also make oil. Honda says idle a cold engine a lot longer to warm it up more completely. They ALSO recommend driving for a long time every month. To really heat up the oil completely.
After doing a interstate run at 70 mph the oil level on the Dip Stick drops a 1/8" lower.
 

stevedan

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Does anyone have input on the best prop to run: Currently a 23 pitch prop but was advised by boscoe99 I was over propped. Yamaha 150 HP 4 stroke with S/S prop. 18ft boat.
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
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16,066
Honda car engines also make oil. Honda says idle a cold engine a lot longer to warm it up more completely. They ALSO recommend driving for a long time every month. To really heat up the oil completely.
After doing a interstate run at 70 mph the oil level on the Dip Stick drops a 1/8" lower.
That's news to me....

What years?

Bought my first (new) Honda Accord in 1988. Have had at least one Honda, usually two, in the garage ever since.

Current daily is a Civic EX with 230K miles
 

99yam40

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Sep 7, 2008
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Does anyone have input on the best prop to run: Currently a 23 pitch prop but was advised by boscoe99 I was over propped. Yamaha 150 HP 4 stroke with S/S prop. 18ft boat.
do a search for Yamaha performance bulletins and find a boat and motor like yours to see what they used
 

stevedan

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Apr 27, 2023
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thanks for input 99yam40,, always like some good information and direction. !
 

stevedan

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Apr 27, 2023
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Update on my post of gas in oil. With the change out of the thermostat, fuel filter, changed the oil & filter, plugs and have been in the water 2 times now, operating at WOT half and have, I "do not" see any more additional oil level or increase, so I am hoping this issues is behind me with this motor. I think maybe the thermostat was a possible problem with my issue, but not sure.??
thanks to everyone who provided input and information, Hope this helps someone else.
 

99yam40

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Sep 7, 2008
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9,085
Update on my post of gas in oil. With the change out of the thermostat, fuel filter, changed the oil & filter, plugs and have been in the water 2 times now, operating at WOT half and have, I "do not" see any more additional oil level or increase, so I am hoping this issues is behind me with this motor. I think maybe the thermostat was a possible problem with my issue, but not sure.??
thanks to everyone who provided input and information, Hope this helps someone else.
did you find what prop was used on a boat rigged like yours in the bulletins?
did it have a different prop than what you have?
did you change prop?
did your porpising get taken care of?
 

stevedan

Seaman Apprentice
Joined
Apr 27, 2023
Messages
46
did you find what prop was used on a boat rigged like yours in the bulletins?
did it have a different prop than what you have?
did you change prop?
did your porpising get taken care of?
No, did not get any additional info on prop, using the same prop at 14 1/2 x 23P
Not sure what was on the boat from OEM, this was the prop on the boat when I bought it, no other prop was given.
as mentioned, same prop 14 1/2 x 23P
peek out at 54 MPH at 52 RPM, running pretty smooth on the water trimmed up as much as possible and still get a good ride.
 
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