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Alpha One Broken after 120 hours?

vanwalsum

New member
Hi Guys,

In august, 2018, I've bought my first (real) boat. After 2 months on a small rib with a 15hp Honda, it was time for something else. It's en 2012 Crownline 18ss with about 120 hours. We've enjoyed it for 7 or 8 Sundays until winter came in.

Yesterday I transported the boat to a boat service to have the carb cleaned, the stern oil, engine oil and impeller changed. This afternoon I received a call that my stern has died. But after 120 hours, is that possible. I was told there is much free play and a grinding noise from the vertical shaft.

Could you have a look at it and tell me if it is a dangerous situation to go out on the lake.

https://youtu.be/Ui8VWVUG2oI

Thank you very much.

Greetings from the Netherlands.
 
Ayuh,...... At 1st glance,.... Yer bein' taken for a ride,.....

The water pump assembly is off, 'n it helps hold the vertical shaft in-place,.....

Obviously, I can't tell whether the bearin's are gritty or not,.....

Worst case, you need a lower unit, not the whole drive,.....

'n at 120 hours, it's possible it was never serviced properly, 'n is junk,.....
Did you check the oil in the drive after you bought it, before you used it,..??
 
I'm with bondo, that free play without water pump and shaft seal is normal. It is possible that it is ruined after 120 hrs but only if there was no lube or water (milky) lube, would have seen a lot of metal shavings in the oil.

Is thus a professional marine marine mechanic who knows mercruiser? No reason a knowledgeable mechanic would have pulled the cone shaped seal off the shaft just to do an impeller unless there was a leak in the lower unit.

was it making a noise when you were using it?
 
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Agreed, the tool to set the backlash pulls the shaft upward, another way to check backlash is to turn the drive upside down . If someone is telling you the drive is shot there not mercruiser mechanics
 
I also agree without the bottom of the water pump housing. Of course it would be that noisy.. Vanwalsum did they show you the gear oil. And the drain screw with the magnet on It?

It would be full of chunky shavings if it was pooched. And the oil would have a metallic look to it.
 
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I'm with bondo, that free play without water pump and shaft seal is normal. It is possible that it is ruined after 120 hrs but only if there was no lube or water (milky) lube, would have seen a lot of metal shavings in the oil.

Is thus a professional marine marine mechanic who knows mercruiser? No reason a knowledgeable mechanic would have pulled the cone shaped seal off the shaft just to do an impeller unless there was a leak in the lower unit.

was it making a noise when you were using it?

SORRY.

A knowledgeable Mercruiser Mechanic changes the Seal Carrier assembly when the water pump is changed.



Have them pull the lower apart, may just need a bearing.
 
SORRY.

A knowledgeable Mercruiser Mechanic changes the Seal Carrier assembly when the water pump is changed.

I guess I stand corrected this was the advice given to me by long time mercruiser mechanic myself several folks I know have used for years (generations really)..." if the seal isn't leaking leave it alone", but this is in a fresh water environment wher 35-40 hrs is typical annual use. Apologies to OP if I gave incorrect advice.
 
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the shaking of the shaft means nothing, That is 100% normal it the disassembled state it is in.

The bearing noise is another issues.
Sounds like there was NO gear oil and only water........

The bearing will be a bit noisy in that state but without being there to feel it there is no telling.

As Chris suggested, A disassembly and fix the bearing if needed.

Make sure they save all parts for your review and the gear oil as suggested if they still have it.

If gear oil was OK and the correct amount came out of the drive then they may be trying to pull a fast one on you........
 
the shaking of the shaft means nothing, That is 100% normal it the disassembled state it is in.

The bearing noise is another issues.
Sounds like there was NO gear oil and only water........

The bearing will be a bit noisy in that state but without being there to feel it there is no telling.

As Chris suggested, A disassembly and fix the bearing if needed.

Make sure they save all parts for your review and the gear oil as suggested if they still have it.

If gear oil was OK and the correct amount came out of the drive then they may be trying to pull a fast one on you........

Ok then i know the shaking is normal. Yesterday i forgot to pull the schaft and then check the free play. The grinding noise you hear in the video was whitout oil in the casing. There were some small metal shavings in the old oil.

Worst case, what can happen if i go on the lake in this state? I never hear anything strange when boating from the rear.
 
Ok then i know the shaking is normal. Yesterday i forgot to pull the schaft and then check the free play. The grinding noise you hear in the video was whitout oil in the casing. There were some small metal shavings in the old oil.

Worst case, what can happen if i go on the lake in this state? I never hear anything strange when boating from the rear.

Ayuh,..... Worst case, it'll run just fine,................................ til it don't,......
 
SORRY.

A knowledgeable Mercruiser Mechanic changes the Seal Carrier assembly when the water pump is changed.

I guess I stand corrected this was the advice given to me by long time mercruiser mechanic myself several folks I know have used for years (generations really)..." if the seal isn't leaking leave it alone", but this is in a fresh water environment wher 35-40 hrs is typical annual use. Apologies to OP if I gave incorrect advice.

Just to expand on why. seal.jpg
On Gen 2 Alpha Drive.
The part I colored red on the picture supports the wear plate. After some use they melt just a little and deform, the wear plate loses support and the pump will cavitate and introduce air into the water stream just like a rotted dam under the pump will do. So for the extra dollars, replace the whole pump and carrier. It's cheaper than a long block. I also replace the water dam in the upper and filler block with the pump. OEM PARTS ONLY, aftermarket will fail.


On Alpha 1 drives using the pressure style pump, you change the whole pump along with the lower housing for the same reason.
 
I've choosen to just bolt the thing back together with new oil and have the boat ready for the weekend. Last 2 days we drove for 6 hours with any problem. But, it's irritating me because it maybe will go wrong.

I have 2 options in my opinion.

1. i've heard that there are imitation brand options for the lower end, could you tell me what are good units?
2. rebuild the lower part myself. What parts or what part kit do i need?

Since it's costing a lot of money, i also want to replace the standard prop. I'm thinking about a Enertia Eco and a Revolution 4. I want a good cruising speed with low rev's. Now it's gooing 3200rpm with about 35 km/u. Top speed 60 km/u with 4600 rpm.
 
1. i've heard that there are imitation brand options for the lower end, could you tell me what are good units?
2. rebuild the lower part myself. What parts or what part kit do i need?

Ayuh,.... The only aftermarket drive out there is the SEI drives, which I've had Great luck with, for less that 1/2 the price of Oem Merc parts,.....

You have neither the tools or knowledge to rebuild a lower unit,....
The tools alone are the cost of a SEI replacement unit,....

If you replace the prop, you need a pitch that allows the rpms at Wot to be as close to 4800 as possible,......
Any lower rpms than yer seein' now, will be luggin' the motor throughout the rpm band, which leads to detonation, 'n holes in the pistons,....
 
Okay. I’ve been to another shop with the lower end. The shop pulled the shaft out an bit, turned, and says there is nothing wrong with it. I drove about 6 hours with it, drained the oil and no metal shavings. So i think the lower end is good and they wanted some money in the bank.

thanks for your help
 
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