898 cooling hose routing

[johnbell47]

Got the 305 chev, or merc 898 running and running good on the test stand. Unfortunately, I bought this motor on E bay for the parts and then rebuilt it. Freeze cracked block. Now it is running hot, O.k when at about 1000 rpm, but when I go to idle, the temp suddenly shoots up. It is putting the garden hose water directly into the riser, which seems to me it should go to the manifold, then the engine, then the riser and out. It has the 6 hose octupuss thermostat housing. I cannot find a diagram of hose routing on the internet, so I need help. I have a manual ordered but it ain't here yet. this is driving me nuts. Also, the right side exhaust puts out more water than the left, the left manifold is also warmer. I have a new thermostat, mounted in the top of the thermostat housing. Boat shop guy said thats where it goes, I ain't so sure, since no diagram i've seen puts it there. Most show it in the bottom of the housing with a sleeve to locate it. I tried to argue with the shop guy, but got nowhere and it does have a machined depression for the stat. Thanks!