alpha 1 gen 1 upper water pocket

[blkzoe]

Dropped the A1 G1 outdrive to replace the impeller. Drained the gear lube and thought I saw the slighest hint of white in the blue lube. Bubbles or water? Removed the cap from the upper unit to look at the gears. Perfect shape, no corrosion. Remenants of the lube looked blue 100%. Sigh of relief.

Then noted the two "water ports" under the cap. Apparently water circulates all the way to the top of the cap of the upper unit. These cavaties contained sediment I obviously picked up during my shallow water adventure this year (we won't talk about that.) What's the purpose of the water jacked that far up the unit? Cool the gears in the upper? Anybody else get sediment in these cavaties? I cleaned them out the best I could without get any crap in the exposed gear well.

Any thoughts? Ever seen a coolant flow chart for the A1 G1 upper unit?

Thanks in advance.

PS here's an image of the cap the cavaties were found under. I really can't find a good image of the water pocket.

 

[Bt Doctur]

basically the flow is from the impeller to the right side of the housing, goes around to the left side of the housing , and into the water inlet hole.
Helps to cool the drive oil.The water pocket cover is on the underside of the upper unit. its where the copper tube goes into.

 

[UncleWillie]

Yes, the water is there to cool the upper drive while on plane and the drive is out of the water.
It still gets considerably warm. (200+ F)
That white powder looking crud that forms on the upper case is from the accelerated evaporation of the water spraying on the very warm drive case.
The racing crowd installs "Drive Showers" to spray down the upper drive case for extra cooling.

After a long run on plane, shut down the engine and sit on the stern with your bare feet on the top of the drive.
Even completely under water, it will be noticeably warm for quite a few minutes.