Island prospector
Recruit
- Joined
- Aug 27, 2013
- Messages
- 2
I purchased a new Mercruiser Alpha 1 Gen 2 leg in Nov 2010. It was broken in properly but in hindsight exhibited a variable intermittent harmonic buzzing noise that at the time was thought to be due to break-in or propeller noise or just general engine noise and could not be isolated. I run an aluminum propeller which has signs of cavitation burns. This noise was not always noticeable. The leg oil was changed after break-in at 20 hours and looked OK and the magnetic plug had some iron fuzz on it. Over time the noise has however increased till now it is more or less continuous generally over 2500 rpm. This noise was thought to be due to the gimbal bearing which was changed at about 100 hours of time on the new leg but without stopping the noise. The propeller was also changed without any change or reduction of noise. The oil was changed again at about 90 hours by a reputable boat repair company. The oil was dark but still green. The magnetic plug showed evidence of iron filings (fuzz) but this was not considered significant at the time and was attributed to grinding gears due to shifting too slow. The leg now has about 118 hours on it. The oil was checked and found to be quite dark and smelled burned after the last 28 hours of operation and there is quite a bit of metal, still fuzz, on the magnetic plug. We now suspect a bearing is going probably in the lower drive line as the noise does not appear evident when not in drive. This has probably been going on since new but the one year Merc Warranty will not help us out as we are past 2 years. In hindsight we probably did not pay enough attention to the iron on the mag plug. My question is before even spending money on disassembling, is it worth repairing or should I just replace the lower leg or the whole outdrive since there has probably been some fine metal floating through the system for some time now?