Hot manifold

[donald]

OK all you experts out there, this one has me stumped.
Port elbow was running warm to the touch so I removed it and cked things out,
hoses heat exchanger (1/2 closed system) all looked good.
Put it all back together and when I ran engine on muffs the starboard side was hot, cked at transum and no water flowing from that side!
Removed that elbow and cked all hoses all looked good, put it all back together and problem went to other side again.
Anyone have an insite to this?
Any and all help would be helpfull.
Don

[jrsick]

Sounds like your engine is not getting the water volume it needs to cool itself.
Are you able to put it in the water to test it? If not, you may want to try a large bin or bucket.
I do not trust the muffs to check the cooling system.

[mmwjr]

First is the hose on full?

Is the boat sitting level, should not make a difference but I’ll ask anyway? If not water will come out the lower side transom hole more.

Use an IR temp sensor to provide actual temps.

Try removing water hoses to manifolds and see if they are flowing the same rate.

As jr said if you can put it in the water to check.

For the future don’t start ripping into things without real temps.

[donald]

I have used a IR for the temps.
As I said it jumps from one manifold to the other.
Engine is running at a steady 165 but one elbow is at 130 and the other at 96.
This seems to be jumping from one side to the other.
I did pull the small plugs on both elbows and I had lots of water on one side and not the other.
I will pull both hoses and ck to see if there is an even flow.
This all started suddenly.
Don

[mmwjr]

Wonder if you have some debris in the raw water side of the HE. Is the a port on the HE for each manifold or one port with an external tee to feed them?

[donald]

Hi Mike
I pulled both ends off the HE and all was clear.
There are two ports for the manifolds and they are clear.
Like I said it changes from one side to the other.
If I take one side apart then it changes to the other.
I puled the small pipe plugs out and had a good flow from one side and not the other.
I do not understand it. It stared after we went to the lake and came home, was getting ready to go out again and had the problem. I always start engine and ck everything the day before going out.
Thanks
Don

[donald]

P.S.
I know there is good flow to manifolds as the fact that it changes sides.
Don

[Gugi47]

Sea Water Pump Impeller?
Maybe the thermostat?

[mmwjr]

Hi Don, little stumped myself. IMO 130* isn’t to high to operate the boat, I would get alarmed if the exhaust meets or exceeds the engine temp.

Did the lake have a lot of sea grass? May have sucked some up. Any signs when you had the exhaust apart?

Since the engine temp is normal the closed cooling including the t-stat are fine. I suspect the impeller is also fine since the engine temp is good and you are seeing water flow at the exhaust. IMO go run the boat and take your IR sensor with you to take a reading as soon as the engine is at normal temp, if the exhaust is no worse keep going but take temps another 10 minutes for 1/2 hour. Return home if it gets worse. Either way report how it goes.

[donald]

Thanks Mike
I was thinking about doing that but have to wait as we have to be somewhere else today.
Also checked to see if the boat was leaning to one side, it did so I moved boat to a place that leaned the other way and same problem.
Will try to get to lake asap.
Thanks Don

PS:
NO sign of anything in engine.