Alpha 1 Outdrive water flow diagram

[downrigger65]

I have a 2007 Trophy with a 4.3 MerCruiser & Alpha 1 outdrive. I have a closed cooling system and I have gone over the flow diagram many times trying to figure out my cooling issues.
I have a thru hull sea water pump cooling the engine system exiting the exhaust risers. I see one inlet at the bottom of both exhaust manifolds and that comes from the thru hull sea water pump. With that what/where is the water flow path from the outdrive pump? What is it cooling?
As many of you know, it's quite difficult to see "everything" around the engine.
I hate to say it but I can't find an outdrive flow diagram. Is there a useful flow diagram posted.
Thanks

 

[kenny nunez]

First you need to drop the lower unit to see if there is a complete pump with the impeller. You should see a pipe that plugs into the top of the pump housIng that is plugged into the water pocket cover in the upper housing.
There is supposed to be a hose on the port side of the bell housing that goes to a fitting on the transom plate. Most times the hose is either removed or has been cut to let water flow through the drive when converted to a belt driven pump. Which is not correct.
Inside the boat on the starboard side around the 10-11 o’clock position there is a male fitting that a hose originally supplied water to the engine. It may be capped off.
Whenever a belt driven raw water pump is used with a stern drive Mercruiser says to connect the 2 incoming water hoses together with a “Y” connection to keep water flowing through the drive for oil cooling. The added feature allows the engine to be flushed out with the standard ear muffs by closing the valve on the through hull fitting.

 

[downrigger65]

Thanks for the info Captain Kenny Nunez
I went out and dropped the outdrive, figuratively speaking, and sure enough, the hose from the OD impeller was cut, dumping right back into the water.
Couldn't find any male fittings but I do see where it goes through the bulkhead.
Thank again for your help!
John