Alpha 1-Broken Upper Housing Driveshaft

[qystan]

Dropped lower to change impeller, this is what I found.<br /><br />

<br />Splines almost completely worn.<br /><br />Dropped upper drive to check driven gear splines, guess what I found.<br /><br />

<br /><br />Fishermark had a similar.<br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=24;t=010374#000000 <br /><br />The drive only had 50hours, its a brand new SEI drive installed last Sept. Suspect its the shaft breakage tat allowed the gear to float and wear the splines away. Gear splines are ok, hardly any sign of wear, gear should be much harder. <br /><br />Suspect that the condition existed for the 50hrs. Remembered that it made a loud grating noise last year. Stopped when lower drive was removed for bearing change. Noise did not return. Lower drive was later changed due to its housing condition, everthing worked fine throughout the year.<br /><br />Just goes to show what 50hrs can do if something's not right.<br /><br />Work ahead...... <br /><br />Qystan

 

[tommays]

Re: Alpha 1-Broken Upper Housing Driveshaft

how is SEI handleing the problem ? or did you not get a compleat drive<br /><br /><br />tommays

 

[qystan]

Re: Alpha 1-Broken Upper Housing Driveshaft

I did not get a complete drive, only the lower drive, the upper is a merc unit.<br /><br />Have written to them, not got a reply yet but that was before I opened up the upper drive and thought it was due to a soft driveshaft. Looking at the upper, I believe the wear is not their problem.<br /><br />The upper was overhauled in Mar 04 by a mech to replace all the bearings and seals. I have just removed the roler bearings of the drive shaft, guess what, the the rollers are Timken but the cups are not. The old cups were never replaced, which would mean shimming wasn't done either. I expect the cups to be Timken as I got all the bearngs from Merc and handed them over to the mech and clearly remember they were Timken. <br /><br />Gave to job to the mech then as I was completely new to sterndrives. This time I am fixing it myself, at least if I have to kick someone I can.<br /><br />

 

[tommays]

Re: Alpha 1-Broken Upper Housing Driveshaft

i believe fishermark or a name close to that had the same upper failure early this year<br /><br />tommays

 

[qystan]

Re: Alpha 1-Broken Upper Housing Driveshaft

Edited to add Fishermark's thread and changed title to be specific.

 

[achris]

Re: Alpha 1-Broken Upper Housing Driveshaft

Good luck.

 

[Fishermark]

Re: Alpha 1-Broken Upper Housing Driveshaft

I feel for ya!<br /><br />That's wild - your upper shaft looks EXACTLY like mine did!<br /><br />

<br /><br /><br />Not to minimize your pain.... but for what it is worth, I'm glad to hear you say that your upper unit was not a SEI unit. I bought the complete upper and lower SEI units to replace my Alpha 1. I am very happy with the result.

 

[qystan]

Re: Alpha 1-Broken Upper Housing Driveshaft

Fishermark<br /><br />Yes, I am also very happy with the lower unit. Biggest regret is having to open it up to change the driveshaft because of this. I only wished I had got the upper as well and could have avoided all this. Got the lower unit fixed, now waiting for the driveshaft and shimming tools for the upper.<br /><br />A few thoughts since I have the drive for a year now.<br /><br />1. I have quite a few corrosion spots and paint flakes, especially at the upper edges.<br />2. Having opened the drive, you might want to note that bearings are made in China. Not sure how good they are, but if they specified the correct wear and load specs, they should be fine. The wear I see is quite normal.<br />3. Have checked their shimming before dismatling, they are spot on.<br />4. The water pump impeller is distorted and needs to be changed. But should note that I had the hose fall off twice while flushing and got wrapped with a plastic bag once. The overheat alarm came on on 2 of these occasions. A firend of mine who also got the drive, his impeller slipped the hub during the first test run. Its a good idea to get theat changed. Btw, our experience over here is that the non-merc impellers fail very quickly, none of the mechs will use them.

 

[Fishermark]

Re: Alpha 1-Broken Upper Housing Driveshaft

Hi Qystan,<br />Thanks for the "heads up" on the impellor. I have an engine mounted raw water pump with a 1.25" thru hull pick up to cool the engine. The only thing the impellor in the lower unit does on mine is route the water up through the leg and then back over the transom. (Some say it isn't necessary... some say it is. I don't know, but I have it set up that way anyway - that's what what Mercruiser recommends). So far as the corrossion goes, I guess I will have to keep an eye on it and touch things up as needed.