Think i blew the 250 xs up

[harrells]

I think it blew up today, only about 60 hours on it. 3.0L 250 sport xs. Was running about 5500 rpm when it reved up and shut down, hooked right. I thought I lost the prop but no. Tried to crank it back up and it seems the fly wheel is locked up. Pulled all plugs and no metal particles on them.

 

[tomoad]

Did your LU locked?

 

[harrells]

Prop spins in neutral, but when I try to start it the starter will not spin the fly wheel. Going to make some calls Monday to find someone to take a look at it. Maybe a compressor issue not sure.

 

[90 5.0]

Pull belt off compressor and see if motor will turn then

 

[Dave Hensley]

Subscribed. I am seeing some issues with the 250XS.....Hope it is something simple. What year is it?

 

[xb03fs]

Subscribed. I am seeing some issues with the 250XS.....Hope it is something simple. What year is it?

Well I trashed my lower unit in short order. Pinion gear broker taking out gears and solehow managed to destroy driveshaft in process....First summer with 3 liter and 1 costly repair

 

[M.ALEXIE]

My buddy has 2 - 250xs's on his 30'cat. 3 years and 3 gear cases later.
I love my 2.5 sport master on my 3.0l. (knock on wood)

 

[xb03fs]

Any idea why 3 liter lowers are less durable?

 

[harrells]

It's on its 4th gearcase in 2 years. Now I think the air compressor is locked up. Motor manufactured in 2012 purchased new late 2013, only has about 60 hours on it. I'll know more this weekend when I pull the belt off and see if the flywheel spins.

 

[M.ALEXIE]

Smell the oil I bet its burnt. I buddy has to change oil every time out.

 

[xb03fs]

Smell the oil I bet its burnt. I buddy has to change oil every time out.

Oil in lower unit?

 

[RoseXB03]

Ooof, sorry man! See ya soon

 

[GotMyAlly]

Any idea why 3 liter lowers are less durable?

Lack of a vent and propensity to be over-filled (pushing out the shift shaft seals)?

 

[harrells]

None of the above for gearcase failures. I use the new merc racing gearlube , change it every 10 hours and always drain 2 ounces out after filling. All the gearcases so far have been manufacturing defects, replaced under warranty. Problems were bad machining in the case at the seals allowing water in. So much for quality control. Wish I still had the pics.to post.

 

[Tim Powell]

Drop the gearcase and bump the key....if it turns over the gearcase is locked up.

 

[Dave Hensley]

Any update??? Have all the issues been with Sportmaster cases? Reason I asked was that I am modifying a TorqMaster for a 3.0 liter motor in the works right now. One more sleeve in it and it goes to Kingston to be assembled. All the sleeves in this motor were installed well below the proper interference fit from the factory. 3 had already started to turn. One had already turned to the point it hung a ring and the sleeve had been replaced. Point is they are too loose from the factory. It is no wonder so many folks have had trouble with them. Of course Mercury reduced the interference fit and started gluing the sleeves in to reduce assembly cost. Anything you put between the cast sleeve and the aluminum register in the block reduces the blocks ability to pull heat away from the piston into the water jackets. Opti's run lean, which means more heat, which means more expansion which exaggerates the loose fit between cast liner and aluminum register. Sound like a recipe for trouble???

 

[harrells]

Dave. All the issues have been with sportmasters. I'm hoping this is number 5 and not the air pump. I should know something this week. I am a little disappointed in this motor and mother merc, as long as they have been building these things you think they would know better. Dave while I have your attention, do you work on these 3.0L opti motors and gearcases? I dred taking it to a dealer for repair.

 

[Dave Hensley]

I do not but have a resource that I trust my work with..... I am past learning new PCM's, sensors and gearcase work but thankfully there are folks out there that have the training. Let me know what you find. My guy is a Merc factory tech.

 

[SLOmofo]

Any update??? Have all the issues been with Sportmaster cases? Reason I asked was that I am modifying a TorqMaster for a 3.0 liter motor in the works right now. One more sleeve in it and it goes to Kingston to be assembled. All the sleeves in this motor were installed well below the proper interference fit from the factory. 3 had already started to turn. One had already turned to the point it hung a ring and the sleeve had been replaced. Point is they are too loose from the factory. It is no wonder so many folks have had trouble with them. Of course Mercury reduced the interference fit and started gluing the sleeves in to reduce assembly cost. Anything you put between the cast sleeve and the aluminum register in the block reduces the blocks ability to pull heat away from the piston into the water jackets. Opti's run lean, which means more heat, which means more expansion which exaggerates the loose fit between cast liner and aluminum register. Sound like a recipe for trouble???

Couldn't a pin be installed to locate the sleeve in the block?

 

[Dave Hensley]

Couldn't a pin be installed to locate the sleeve in the block?

Have done that. Gary the only problem I see with that in a lake motor that sees prolonged runs at higher temps is that if you don't have a tight fit between the cast sleeve and the aluminum block register it doesn't cool very well. Guessing there are chemicals and compounds that might be used to fill in but the glue the factory has been using, Loctite retaining compound, isn't the answer. My research is not scientific. I could be wrong. I have just seen the before and after several times.