Mercruiser 4.3 Alpha One Roar

[cmala]

I have a mercruiser 4.3 with an alpha one. The numbers on the side of the upper unit are 1.84R and looks like OC685819.

I took it in to get winterized. I had never done it before and didn't have time to figure it out and get it done because I always wait till the last minute to do things and $150 to winterize and change oil wasn't too bad.

While it was in the shop, he said the drive had no oil. After taking it off, he found the yoke had some damage that he said damaged the oil seal and caused all the oil to leak into the bellows. He replaced the yoke and the seal.

He also said that the drive has had water in it as some point and one of the u-joints was rusted. Replaced that as well. He said after this the unit still was roaring while running. He took it apart and said he found some pitting in the bearings and races in the upper unit and suggested that I replace the upper unit. He showed me the attached pictures as evidence of the problem.

I have looked at the FSM and online parts diagrams to try to figure out what part this is and why it would cost around $800 in parts to replace but I haven't been successful. He quoted me $450 for a used upper. I told him that I would take care of it before spring and to just put it back together for now. He said to go ahead and run it like it is but listen for the roaring to get worse..... Doesn't sound like a good plan to me.

Anyway, does anyone have any suggestions? I don't have any special mercruiser tools but am reasonably mechanically inclined and have access to machine tools so I can make metal tools as required.

I got this boat around July of this year and had some work done to the lower unit but have never had the upper off till today. When I put the lower back on, I did fill it with oil according to the FSM. We ran it for several weekends over the summer and I didn't have any problems.

Thanks
Craig

 

[bruceb58]

You fill it from the bottom?

 

[Bondo]

Ayuh,.... Welcome Aboard,..... Did the Mechanic find the reason for the bellows fillin' with water,..??

That was probably the Start of yer issues,....
Water in the bellows would have rusted the u-joints, 'n the yoke that was replaced, allowin' the oil in the drive to escape the drive, 'n water goin' in the drive,...

That bearin' race looks Beat, Badly,....
That means the gears are worn too, which means yer lookin' at a Mercruiser parts bill of 'bout a Grand,...
The gear sets, are Sets, 'n the bearin's are replaced as Sets,...

It'd be cheaper to buy a brand new warentied SEI drive from iboats, than to tryin' fix yer's,...

 

[cmala]

Thanks for the replies. Yes, oil pumped in from the bottom till it ran out the top.

Well, if the gears have to be replaced then I guess that explains why he said a used upper for $450 would be cheaper.

I have considered the SEI drives. Since it's winter, I guess I have some time to get ready. If I go that route, I will just get the complete SEI unit.

I'm not sure if the previous owner addressed the water issue. I'm thinking he did but I guess that's something I need to figure out.

 

[bruceb58]

Whenever I am going to take my boat out, I check the gear lube level.

This is also a reason you need to take your drive off every year and change the bellows every 5 years. Once water gets in the bellows, it corrodes the drive shaft leading to a seal failure and your fluid ends up leaking into the bellows. I know this boat is new to you but you need to do this. I probably would have done this after I bought the boat. Now you know.

 

[Grub54891]

I'd be pulling tgat drive and really go through the bellows, and the gimble bearing can also roar pretty loud.

 

[Fishermark]

...
While it was in the shop, he said the drive had no oil. After taking it off, he found the yoke had some damage that he said damaged the oil seal and caused all the oil to leak into the bellows. He replaced the yoke and the seal.

He also said that the drive has had water in it as some point and one of the u-joints was rusted. Replaced that as well. He said after this the unit still was roaring while running. He took it apart and said he found some pitting in the bearings and races in the upper unit and suggested that I replace the upper unit. He showed me the attached pictures as evidence of the problem....

I agree that your best bet is to buy a new upper from SEI... but I would have to question why the shop replaced the yoke and put it back together in that condition. You have to remove the top and in order to do the work and that damage should have been evident. THAT would have been the time to recommend replacing the upper with a used unit - or fixing the bearings, etc.

 

[81 Checkmate]

I have to agree with fishermark......why didn't they notice the damage when replacement of the seal. Id question the shop!