HELP! MTU part number help please

Hi all. I had an overheat problem with my port engine last night which was my first run of the season. I did move the boat from where it sat in the ater over to my club three weeks ago and it got up to about 215 deg. before I got it into it's slip. I havent been out since.
All indications point to a simple thermostat but I need to find one by Friday morning as the mechanic who helps with the bigger stuff is going away so if I can find the part, Ill be good to go for a big charity cruise Saturday night.
If anyone can help and tell me what a part number is for a '94 MTU 12v183, I'd greatly appreciate it. I'll drive where ever I have to to pick it up.
My problem is that I have no idea where these are located on the engine but I do have a manual which I'll look at tonight.
If you want to know how I came up with thermostat, the raw water is pumping just like it always does. Engine temp creeps up slowly (running slow) but the heat exchanger on the other motor is very warm, just lke the engine. On the one that's overheating, the heat exchanger is cold which leads me to believe the thermostat got stuck over winter layup and won't open to cool the sntifreeze.

Thanks very much for your help!!
David Dall

Thanks. I'm about 75 miles from Johnson & Towers (I'm in CT) and have them on my list to call in the morning.
Next up, I have to figure out where it is in this engine LOL. Give me an old big block GM and I'll take it down to the last nut & bold then rebuild in no time but these are comfusing MTUs!

No, not a suden problem. It happened on the first idle trip about 4 miles from in water winter storage so it;s been sitting for months. Raw water strainers puping normal amounts of water. The weird one is that the engine thats the right temp, the heat exchanger is warm. On the overheat engine, the rxchanger is cold which tells me water isn.t circulating which should mean stuck thermostat.
Would you agree/
I'm going to get the serial numbers out of my books for Stewart and Stevensen Atlantic to see if they have one. then I need to figure out where it's lovated on the engine.
I can rebuild an offshore racing powerboat to the last nut and bolt but I don't kow where anything is on these 12v183s!

Stewart and Stevensen not only gave me all the part numbers but also a schematic of where everything goes. Problem is thanobody has the parts. Even Johnson and towers. Stewart & S is putting a rush on gaskets, o rings, thermostats etc. the parts dept is great. They said if I need help, they can get someone there next week. My regular AMT guy is in FL but after looking at the breakdowns, it appears to be a pretty simple job.
I’m also one that if something goes on one engine, the other isn’t far behind so getting everything for both. Time for belts too. I found one in the bilge but that was from the alt and it’s a double pulley. I’m shocked that MTU didn’t put a double on the cooling pump. An alternator doesn’t have the same concequences as a broken cooling pump. I hear major meltdowns happen on the 12v183s when this happens. I bought the boat with a new port engine because of this.

Hey Guys, you're all right.
Nope, not the thermostats. Changed out the circulating pumps, thermostats and all matched belts.

At idle, Port motor temp rises slowly till about 215 till I shut it down. Starboard side shows 175 at idle but after shutting down port side (idling the whole time), I brought the rpm up to about 15oo. Black smoke like a bad injector then suddenly the temp shoots up till the pressure relief cap on the coolant tank BLOWS out steam and the gauge goes up immediately. I have a nice 3rd degree burn on my mid torso side to prove how hot it got.
After circ pumps & stats changed, exact conditions repeat.
Strainers are clean and when apart, I opened the valves and water gushed in to the point I could sink the boat in minutes. Raw water pumps on the way but I don't think it's the issue as the water comes out of the exhaust just as it always did.

The boat sat in the water for the past two winters. I'm starting to think like you with cogged heat exchangers. any other thoughts. I'm absolutely sick about this The summer is half over and we havent been out more than a mile twice, once when it happened first run on the 4th and second to see if the repairs did it.

Stewart & Stevensen helped me out as my usual friends at AMT are down south. S&S is scratching their heads now. They did't see the black smoke on the stbd. side because it only happens when I give it a little throttle under load. It runs perfectly at the dock even when run up to 2000rpm for a second.

Could it have anything to do with the strainers outer portion? They sit horizontal and I mean not cleaning the strainer themselves, should I take apart the outer glass housing and see if that area is clogged? There was a little crap and an oyster shell in one but nothing to clog the strainer. Perhaps the outer side? I'm getting wishful now. I'm betting cracked something and my only thing to look forward to is over before the season starts.

With everything else going souir in my life these days, this is the last thing I need and I'm literally nauseous.

Thanks for your thoughts!
Dave

Stewart and stevensen did the work as my usual AMT guys are in FL. Hopefully they will be back this week and can get it solved. As far a what's gone into it, the impellors haven't been replaced since I've owned it so all the better. I'm thinking head gasket or crack too. What caused it is the real question. Possibly the winterization wasn't done properly. The same yard does it every year but who knows.
Summer's half over and I'm utterly depressed on every front.

Thanks everyone so much for all of your professionsl insights. My MTU guys got back fro FL today and will be on the boat tomorrow. I hope it's nothing major but I doubt it's something simple, all the simle things have been done.
Hopefully I can give some good news and begin my summer in the midddle of August instrad of swinging from the garage rafters.
Thanks again,
David