Overheating and noise in stern drive and a mystery part.

[Boxsterjones]

I am new to this forum so hello everyone. I have a 2002 Bayliner Capri Classic 2150 with Alpha 1 Gen 2 stern drive. After the boat sitting in covered storage for 2 years, I pulled it out just a few weeks ago and got it ready for use this season. After changing engine oil, spark plugs, all filters, and gear lube in stern drive I put the muffs on and started it up in the drive way. I added fuel additive and half a tank gas before hand. Engine ran rough at first but ran smooth after 5 mins. Took drive out of neutral and engaged forward. Had a little bit of clatter, but it did seem much to worry about. Engine temp rose above 180 and engine overheat alarm went off. I turned the engine off and checked muffs for proper fit. Let engine cool down for 45 mins and tried again. Same results but noticed I wasn't getting much water returned thru bellows. A neighbor who is a boat owner also suggested that I check out raw water pump/impeller. raw water pump/impeller look good with the exception of bent blades. No rubber debris in housing. I am going to replace the pump while I have it open anyways. While detaching lower unit a piece fell out from somewhere and landed on the ground. See Attached Photo. I have looked thru all related diagrams and cannot find this part anywhere. Five years ago, bellows were replaced after engine replacement due to winter damage to block. (I have learned my lessons the hard way.) could it have been left or dropped in lower unit by accident?

Back to overheating issue. When turning drive shaft on top of LU clockwise, seems like there is clanking noise everytime you twist the drive shaft with bit of play just as you turn it again. Missing teeth of gears???. I have looked into replacing the gears but I think with all the time and purchase of some of the pullers/tools that I would need it may be better just to purchase a new LU (The SE116 replacement unit). Any advise / help / comments / suggestions are very welcome.

 

[alldodge]

The is a piece of your exhaust flapper. When they break they fall into the exhaust and reduce water flow and therefore more heat and less power. Remove your exhaust elbow boots on top and have a look inside

 

[Scott Danforth]

flappers fall because the rubber bits are burned off when the motor looses water flow and the hot exhaust goes from 220F (wet) to 1200F (dry - no cooling water)

 

[thumpar]

Check for the other pieces of the flappers. If you have a V motor you have 4 if you have an inline you have 2.

 

[harringtondav]

Have you driven this boat before? If so were there any shifting problems or unusual O/D noises? The Gen 2 Alpha is a rugged design, and if maintained will run for years with an occasional seal kit. Has it hit anything? It takes a severe impact or operating w/o lube to damage the innards. The gear teeth can become pitted, but this is unusual with annual lube changes, unless someone tinkered with that gear set/bearings and didn't shim or preload correctly.

The top cover on the upper gear case comes off with a 12 pt. 3/8 socket. You can see the input gear and part of the pinion. If the drive is off you can rotate the yoke shaft to inspect all the gear teeth. Mind that O ring on the cover. Best to replace it.

I say fix the cooling issue, and run it in the water with a good ear on the situation.