Alpha One died help please

jollymon

Petty Officer 1st Class
Joined
May 2, 2002
Messages
293
Yesterday I was out on my boat, running at about 3000 rpm, when all of a sudden the RPM's shot up, the tempature rose, and the out drive stopped working.

The outdrive acts like you are in neutral in forward and reverse.


Any suggestions or ideas. I hope to have the boat pulled today and taken to a mechanic, but I would love to know what I am facing.

The guy I bought the boat from was on the boat at the time he was even driving it. He seems to think that it the upper half of the outdrive.

What does everyone here think?
 

Haut Medoc

Supreme Mariner
Joined
Jun 29, 2004
Messages
10,645
Re: Alpha One died help please

Pull the drive & see if it will go in gear....
If not, it is the drive....
Possibly a shattered drive gear or a snapped drive shaft....
The grooved ones can be prone to that.......
Inspect the input shaft splines for signs of unusual wear......
The splines should be square, not pointy....
If the drive will go into gear on the bench, I would suspect you smoked the coupler.....
Check alignment with the alignment tool.....
Inspect the coupler area for signs of rubber, metal shavings through the gimbal bearing & with a flashlight....
Again the splines on the coupler should be nice & square, not pointy.....
If it is the coupler, you will need to diagnose why you are having alignment issues.....;)
 

45Auto

Commander
Joined
May 31, 2002
Messages
2,842
Re: Alpha One died help please

Sounds like the coupler died. It's a splined hub bolted to the flywheel of the motor that the outdrive shaft slides into. Once the splines strip out the outdrive shaft stops turning and the waterpump stops (since it's in the outdrive on an Alpha) and the temp goes up. Not real unusual for them to wear out if you don't check the alignment every season. Sometimes just old age will get them, how old is the boat?

Not a big deal to replace once you get to it, kind of a pain to get to since you have to remove the engine from the boat.
 

jollymon

Petty Officer 1st Class
Joined
May 2, 2002
Messages
293
Re: Alpha One died help please

I spoke with the mechanic today. The boat will be ready to launch this afternoon.

It was the upper unit. I was lucky the guy I bought the boat from had a spare upper unit. He also helpped me pull the boat and tow it to the mechanic.

All in all, I got very lucky. 48 hours from blown outdrive, to pull boat, trailer to landbased mechanic, and repaired!!!
 

wca_tim

Lieutenant Commander
Joined
May 28, 2007
Messages
1,708
Re: Alpha One died help please

just make darn sure that he got all the pieces of gear cleaned out of the lower unit... I would be really tempted to change the drive lub after the first couple of times out to catch any pieces of gear that may make their way to the bottom...
 
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