Cooling system diagram for '96 Evinrude 200?

[Keyboardman]

Hi all, running on muffs, the new to me Evinrude 200's port side cyl bank seems to be getting a little hotter than the other. While the right side cyl head is just warm to the touch, I can hold my hand on the port side only a few moments. I'm not getting any overheat alarm. I've had to clean out some debris/scaling from the tell tale that was stopped up and was wondering how the cooling system works on this engine. My factory service manual shows how to replace the thermostat, blow off valve and the water pump but it doesn't go into any detail on the cooling system itself. I'm planning on removing the thermostat on the hot side and check it and the hoses for any clogging. I've wondered about how to descale the cooling system and also just how the system works. I've found nothing so far as to any kind of diagram on it. Would anyone have some knowledge they could share with me? Thanks.

 

[dingbat]

Have not run mine on muffs ever. Always use flush port.
One side is always warmer than the other. Water in one side, out the other

When was the last time the water pump was changed?

plumbing diagram is a fold out in the manual

 

[Keyboardman]

Well sure enough, right there in the back of the book is the diagram. Thought I'd looked at every page. LOL!! I've been running it on the muffs after replacing the VRO pump and verifying that the NO Oil alarm is working and also that the pump is pumping oil with the oil hose attached. I assumed the back flow port was just for flushing after use? Seems to have plenty of water coming out the tell tale and the water pressure gauge shows about 5 psi at 1500 rpms. I have a new water pump kit to install and plan on doing that and a LU gear lube change prior to putting the boat in service. From what I can see in the diagram is that the water flows in the same way thru each cyl head then out. I would assume that each side would be at the same temp? I'll pull and check the thermostat tomm and report back any findings. Thanks.

 

[dingbat]

I assumed the back flow port was just for flushing after use?

As I said earlier, I don’t own a pair of muffs. Just screw hose in port and fire up

Seems to have plenty of water coming out the tell tale and the water pressure gauge shows about 5 psi at 1500 rpms.

Could be a false reading if your running on hose. I change water pump when pressure gets down to 3 psi at idle (~700 rpm) in the water. Runs around 30 psi at cruise (4,300 rpm)) with new pump

I would assume that each side would be at the same temp?

Honestly couldn’t tell you. I have no temp gauge and have never over heated in the 3,000+ hours I’ve put on this motor. First power head went 2,200+ before sw eroded out the sealing surfaces of the heads. The second power head has 800+ hours at this point.

 

[Keyboardman]

If I run it with a hose into the back flush port how does the impeller get any water to it and not burn up? My understanding is that the flush port is there so you can flush the engine if the boats in a slip and you can't run it on muffs. That and the back flush action on any sediment that might have been picked up in shallow waters.

 

[dingbat]

If I run it with a hose into the back flush port how does the impeller get any water to it and not burn up?

What good is a flush port if it burns up the impeller if used for it's intended purpose?

My understanding is that the flush port is there so you can flush the engine if the boats in a slip and you can't run it on muffs. That and the back flush action on any sediment that might have been picked up in shallow waters.

That is one of the functions.....obviously not the only if it can used in place of muffs.

 

[Faztbullet]

Put a impeller in it....