87 yamaha blockage in water passages

Hi everyone,

I have an 87 yamaha 115, and the right two cylinders are getting really hot after running just a couple minutes while the left two stay a good temperature. It has good stream of water coming out of it, it even pisses with just a hose on it. I replaced the impeller already. I ran it without the right thermostat in and it stayed cool, but then I swapped the stats and ran it with both in and had the same problem. Already took off the water jacket cover and there's no blockages I can see. Does anyone know which direction the water flows in this motor? I'm assuming it flows through the left side first, so there should be a blockage somewhere between the right thermostat and the end of path. Any suggestions would be greatly appreciated. Thanks guys!

Carson

Was the impeller you changed in 1 piece? Drop the LU and back flush thru the thermostat opening using a brass garden hose nozzle to get the water pressure up..

I agree with guyjg...I once had a 25 Suzuki with overheating problems...2 pieces of the disintegrating impeller were carried upstream by the water current and had lodged in the 90 degree elbow just entering the lower unit and had blocked the water passage. I think that it's reasonable to conclude that there is at least a partial blockage somewhere.

So drop the lower unit and spray a hose through the thermostat opening? The impeller was intact when I pulled it. Is there any sort of liquid cleaner I can run through to clear some of the buildup out of the water passages?

Run it in a drum full of salt-away.