Busted Alpha One Gen Two Outdrive

[Aussie230SD]

Here in Australia, as many of you would know now, the weathers getting hot. Back on the 6th of October, I took the other half out for the day with our 2008 Sundeck 230 (now pretty much a 240). Unfortunately the day ended when the Alpha outdrive suddenly gave up while very gently accelerating. Took over an hour to be towed back to the boat ramp. This is not the first time this has happened, this being the second failure of the outdrive in less than five years since I purchased this boat new.

I know the 350 MAG engine is at the high end of the Alpha One's capabilities, however I never expected this trouble. Surely neither did Sea Ray otherwise how could you offer this combo. The upper gear ratio is 1.62:1

I am starting to get the feeling that maybe the Alpha outdrive should never have been offered in combination with the 350 Mag (300HP) engine in a boat that weighs 4,850 lbs dry. I am hoping the local Mercury dealer can help out, but I have been waiting over two weeks now and anxiety is starting to creep in, hence this post.

Interested in opinion's regarding a long term solution. Any others out there with a similar story? The boat is not used for watersports, occasionally see's WOT (47mph) for maybe five minutes at a time (my favorite part of the cruise), and is not subjected to hard acceleration.

 

[saopm]

You might want to check the coupler. My bother thought his Alpha outdrive was gone but it turned out to be the coupler. The bad news was that he had to pull the engine to replace the coupler. The good news was the outdrive was fine.

 

[Aussie230SD]

Upper gears are gone. Very messy when a gear tooth breaks off. In this case, (and the previous) the upper housing has been fractured/punctured resulting in transmission fluid bleeding out.

 

[Ten Years Gone]

edit

 

[julians]

I had a similar failure (upper gears failed), when my boat was 3 years old/200 ish hours. Except my boat had the 5.0mpi not the 350mag.

I had the drive rebuilt and it was ok for another 4 years, 200 ish hours, until I sold it, I presume its still ok now.

I just put my failure down to it being a manfacturing defect, rather than too much power, but maybe it was due to the alpha 1 drive not being up to it, who knows.

 

[CliffA]

something to consider....i believe from looking at your signature photo you have a stainless steel prop.....i don't know if this applies to your situation, but if you hit anything (stump rock, etc.) with this very strong prop while cruising there will be a tremendous amount of shock sent through the Alpha drive and easily can damage or weaken the upper gears in the drive....i have personal experience with this scenario.....that is why i have switched to using an aluminum prop.....the aluminum prop will sacrifice itself if/when you hit something and greatly reduces the chance of damaging the outdrive.....in the US aluminum props are cheap....i can get a new 4 blade aluminum prop delivered to my door for around $100....i was paying nearly that much to have my stainless steel prop straightened out after hitting something.....and i have noticed no difference in performance between the SS and aluminum props....

cliff

 

[Gary Hill]

Aussie,

I work in the gearing / spline world. "In general terms" and I do mean general terms, we usually start looking at single tooth failures as shock or defect related issues. Then conversely, multiple tooth failures as lube or alignment issues.

Post some pic's of the gears if you have any.

Hope this helps in some small way.

Regards,

 

[magstang1]

I had a 350 mag and alpha combo in my first boat, a 21 foot powerquest cuddy cabin. I ran a 3 blade stainless prop for the 8 years I owned it. I wouldn't say I abused that boat but it saw plenty of "spirited" driving. Other than changing the gear lube annually, and routine maintenance like water pump and bellows, I never had to touch that drive. It was 100% reliable.

 

[Bt Doctur]

I have 3 customers who swear they never hit anything and all have lower unit destruction.All have a big ,heavy SS prop. Alum prop customers have no problems.
Normally the gear ratio for the 5.7 is 1.50-1 not 1.62-1

 

[julians]

I have 3 customers who swear they never hit anything and all have lower unit destruction.All have a big ,heavy SS prop. Alum prop customers have no problems.
Normally the gear ratio for the 5.7 is 1.50-1 not 1.62-1

I can categorically state I never hit anything , for one I boat in the sea and never go anywhere near the shallows, and two, the prop was perfect and unmarked, as was the rest of the drive casing etc.

If it makes any difference I was running the merc hi five stainless five bladed prop.

My failure was a single tooth had failed, the oil in the drive was changed annually, and was not showing any signs of water contamination when I drained it after the failure.

 

[Bt Doctur]

We`ve been kicking around the idea that the mass of a SS prop suddenly going into gear might be the cause. . On muffs AL ones mostly a loud click, SS ones a very loud crunch. Bravo drives dont seem to have this problem because of the cone clutch. Too high of an rpm setting dosent help either.

 

[magstang1]

I would surmise that the resistance of the prop spinning in the water would negate any difference in mass between the aluminum and stainless. The water would act as a shock absorber.

 

[Bt Doctur]

you would think so but the water has its own resistance, trying to start spinning the SS mass is where the shock load comes from.

 

[Aussie230SD]

Thanks for your reply. I accept that with the SS prop, the gears will go before anything else does. A few small nicks on the edges of the prop over the years, mainly from power loading the boat onto the trailer at low tide, never a solid hit, and none close to the time of the last failure. I like to run up to 40mph (off the speedo) or WOT (45 - 47mph) at times, and I am told that this is a contributing factor. I have never seen more than 5000 rpm. I would not have though that I am part of the problem, but am told that a maybe I am with a Alpha drive. In other words, yes the combo needs to be nursed, and maybe I don't nurse it enough.

 

[Aussie230SD]

Has anyone wondered why the Alpha One is still offered by Sea Ray (in the Sundeck 240) with a 350 MAG, in a package rated at 300hp, when the 350MAG actually puts out 325 at the "flywheel? So in other words, a outdrive rated at 300hp, is coupled to an engine that puts out 325 hp, with a net result of 300hp at the prop.