Found Dry Coupler after pulling Bravo 3

[BUSTMUP]

Last fall I purchased a 2003 220 BR with the 350MAG/Bravo 3 and 200 hours on the boat. Came to this site and learned a lot from everyone on procedures, tools, alignment tool and drive stand needed to pull and service the outdrive. Thanks!!! I also have the Bravo service manual.

This past weekend I pulled the outdrive and the splines are dry. :wow: I had to take a scratch awl to dig the hardened grease out of the splines on the drive shaft. The male shaft looks good with very little wear.

Next I inspected the coupler splines. I took a long screwdriver and taped a toothbrush to the end and cleaned the splines on the coupler. I can clearly see the splines on the coupler are worn. They aren't pointed at the tops, but the sides are worn, I'm guessing about a third...maybe less, but no way to accurately measure. Also the engine is slightly out of alignment, because I can't get the alignment tool fully inserted. The grease tracks tell me the engine must be raised slightly.

My question... Does anyone have any idea or guess on how much longer this coupler will last? I know it's tough to gauge without seeing and I can take a picture and post if that will help. My thoughts are to correct the alignment, grease the coupler and drive shaft with spline grease and keep it greased well this year and probably get the coupler replaced at the end of this boating season along with the water pump impeller that is extremely difficult to access.

I know it's a gamble, but I'm looking for some feedback/experience on coupler wear and life expectancy.

Thanks,
Jeff

 

[JimG]

When the coupler fails, its usually the hub that spins out, not the splines. I think I got about 500 hours on my previous boat before it spun out. I boat on a lake with lots of people so I was in no real danger... although its a terrible sound and bad feeling to be dead in the water. :smt013

I believe my merc mechanic recommended greasing the couple every 50 hours. I could get to the grease fitting from inside the engine compartment.

 

[SeaRide]

Jeff,

I would have the coupler changed now as well. At some point, it will fail. When?? Who knows. However, with my luck it would fail during the middle of summer when your shop has about 25 boats in front me - there goes the summer. Odds are you can get the boat in for service this week and have it back in no time. While the engine is out, other wear items such as hoses, exhaust manifolds, spark plugs, plug wires, the impeller and etc. can be inspected and changed easily.

FYI, I had mine changed late last spring after eleven years as the coupler would not pass the "wobble test" with the alignment tool inserted.

 

[Hampton]

I hate this aspect of stern drives. Mine was worn beyond repair at 13 months age on my '97 250. Dealer told me I failed to service it. I showed him my receipt that I paid him to do it. We paid to have the back seat taken out, they paid to fix the rest. After that, I took over my own upkeep. It was a pain, but I greased that thing every 6 months. After another 9 years, it was fine.

 

[David Paul]

I would change it out right away. The fact the engine is out of alignment bothers me as well. The gimbal bearing probably has a lot of unnecessary wear on it as well so be sure to check it out especially if it hasn't been lubricated in 200 hours either. The coupler hub itself has probably been stressed and even if the splines hold up the hub could still fail.

 

[BUSTMUP]

Thank you for the replies. I appreciate everyone's input and these are great points to consider. I know the correct answer is to change it. Preventive maintenance is smarter than correctiver maintenance. I need to decide soon before the local marine mechanic gets too busy. He said around $1K to pull the motor plus parts. I'm guessing around $2K if I take SeaRide's great suggestion of replacing other serviceable items like hoses, spark plugs, plug wires and the impeller.

The gimbal bearing had plenty of grease. It looks and feels new and I'm pretty sure the previous owner greased it. Today I checked and verified the coupler has aluminum splines vs. steel splines. I’ve read that when replacing, go with the steel splined coupler. Does anyone have any experience, information or recommendations in this area? I obviously don’t want to replace it again.

Thanks,
Jeff

 

[SeaRide]

Jeff,

Mine was replaced with the steel version. The gimbal bearing was about $130.00 (part only). You may as well have the bellows checked as they are about eight years old.

 

[mwph]

He said around $1K to pull the motor plus parts. I'm guessing around $2K if I take SeaRide's great suggestion of replacing other serviceable items like hoses, spark plugs, plug wires and the impeller.

I don't know your shop's labor rate, but $1K sounds like a bargain compared to what I had to pay. Get a clear understanding off what is to be done & let him have at it.

 

[BUSTMUP]

I'm considering pulling the motor myself. I've done major vehicle maintenance in the past. Pulled and replaced an engine, removed a manual transmission and replaced serviceable parts. Pulled and replaced heads, intakes and other engine components. Any opinions or comments on doing the work myself?

I'd like to replace the aluminum coupler with the steel coupler. Part number 861523A11 appears to be the correct Bravo steel coupler. A lot of research shows this if for heavy duty work and low speed applications. I have a few questions.

1. Any idea why Mercury offers both aluminum and steel?

2. Are there any drawbacks to replacing with steel?

3. What are the pros and cons on both?

Thank you in advance.

Jeff