Brown-Colored Water at Exhaust ?

[neilpride]

Aloha!! hey i see something this morning when i start my perkins 4236 that drive me nuts!
When i turned the engine this morning i see in the first 20 seconds the exhaust water turning brown and smelling very bad , this lasted for maybe 15 or 25 seconds , after it has become clear like always, i check the raw water filter for something weird there, is clean, i check also the impeller for traces of something , nothing, is clean and ok.
The engine is a perkins 4236 , run perfect, no oil isues, no coolant isues, always run at 80 degress, so , Anybody experience something like that.
Any ideas where to look at the engine...
Thx..

[motion30]

Do you have a steel muffler or pipeing?

[zeehag]

is either rust for a minuet or coul dbe a dead critter crawled up into your sea strainer. if all else is good, is ok. consult with your mechanic if it persists. my yanmar did that, but without the stinky part and was only rust fora minuet. check the mixing elbow, if you have one, also.

[neilpride]

Nop, the exhaust mufflerr is fiberglass , the exhaust elbow is a custom made piece of nice stainless steel and is in good condition because we check it last year , so idk, very weird...

[neilpride]

Yeahh Zeehag, thats my first idea, some criter suck in the raw water inlet, but anyway i dont find any trace in the pump or filter..

[zeehag]

octopi break down well and fairly fast, are soft and fit into every nook , worse than spidey. make a helluva stinky in their process of decomposition. i have only found remnants of live ones, never found a dead one....

[Target9000]

When you say that it smelled bad, can you clarify? Was it like a rotten odor? Vegetable type matter rot? Animal rot? Sulfurous smell? Like exhaust? Sewage?

[zeehag]

if the smell is of rotten eggs, then is stagnant salt water just sitting in the engine with the rust .... will go away when the seawater is circulated thru it well. so you have 2 possibilities so far for stinky water......

[neilpride]

The smell is like something like a mix between sewage and sulfur , idk how to explain , i never smell something like this in the past, right now im runing the engine to 1800 rpms and everything looks fine , water is clear and temp about 80.
But the rust isue ?? idk, the only part in the engine can be rusted is the elbow , and the elbow is stainless steel and is ok, because we clean and redone all the raw and fresh water systems 1 year ago.

[zeehag]

but your block and waterjackets are iron, yes, like my perkins?? rust will come. it will go away.
sounds like smell is stagnant sea water. it too will pass. you should be fine.
if rust does not go away is sign of more serious stuff. if it goes away fast and your engine is within the norm while running, you should be fine.

[Target9000]

How long did the motor sit before the startup this morning? Next time you shut down and restart try to capture the initial shot of water out of the exhaust in a bucket to examine what it could be. It may just be clear. If it is wait until the next time it sits for a while and then try to capture it.

I'm guessing you let it sit for a while and perhaps something rotted in the line that got shot out and didn't leave any leftover behind.

[nv5l]

I assume you have a heat exchanger. Have you checked it and the coolant reservoir? What does it smell like?

[psneeld]

interval between starts?

[zeehag]

do you leave your engine water intake on or do you turn it off when you leave boat.....

[psneeld]

I would think it's fresh water cooled but if not...then what you ar seeing is completely normal....