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WHo si the Mercury 300X outboard guru

Booshy

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I have a Mercury 300x on my boat that has been sitting for some time. 3 years with little use. I freshened up the gas a bit but never touched the injector oil.

Last trip one of the motors poped a bit at idle but then cleaned up and we we headed up river. Two miles up river one motor stopped. I could not get her to turn over.

I limped back to the dock on one running Motor and pulled the boat out of the water. The locked motor would then turn over but I didn't fire it.

A Mechanic put a bore scope in and said I have some scoring and damage on two cylinders.

He called me today and said he talked to Mercury and they sell the head for that motor for $9000 plus (core) plus labor and parts to tear down and replace the other stuff. BIG BUCKS Ruined my day a little.

I am blown away. These motors have less then 190 hours on them but assume I should have been more careful with the gas and oil situation. Dont know if that oil or oil pump gum up from sitting. Kind feel like
I should have cleaned and serviced them

Is it true these heads are not honable? If we tear the engine down and there is just some score marks I hate to spend that kind of coin to fix this.

Who should I talk about these 300X motors?

.






***Please move this if i posted in the wrong section
 

HavaToon

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Take it to Joe at DBR/Havasu Hot Laps, they are the 300x guru and are straight shooters.

Another great shop is Fallon, again Gill is a straight shooter and very fair.

And yes high quality fuel and oil are the #1 things needed to keep 2 stroke OB's happy.
 

ONE-A-DAY

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Yes they are not honable since they are nikasil plates. Cost for a powerhead rebuild is easy $5000 plus, so correct fuel and oil mixtures is key.
 

28skater

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Mercury stopped making 300x long blocks and the few that where left in inventory sold very quickly. Most likely your dealers is getting a re-manufactured long block check the Mercury part # 61-840756A04
 

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