1993 454 Magnum - Proper Engine Temp?
 

I've had this boat about a month. It is a formula, with a 454 magnum carbureted. I'm not sure what generation that makes this engine (V maybe??).

It tends to run around 140-150 degrees. That seems a bit cool to me, but I've never had a boat like this before. Does anyone know what the proper/oem thermostat should be for this engine?

sounds like you don't have any thermostats installed.

It goes by engine serial whether it takes a 140 or a 160 t stat for the 1992 thru 1994 carb 454 mag. You need to post ur engine serial number to get the correct one. Boat owners need to know this - ENGINE SERIAL is the most important thing to know along with your outdrive serial number. Why so you can follow proper procedures and install the proper parts for your app. Year of the hull means nothing. Service manuals go off the same info = engine serial number if working on the engine and drive serial number if working on the outdrive. FYI

140-150 water temp is normal for a carbed 454mag.

Perfect.

Not if it needs the 160 t stat - its running to cold and temp gauge is spot on and that will cause rich conditions especially at idle speeds

Serial number needed

He mentioned it's carbureted.

If it was EFI, I would 1 million % agree.

My lord carb apps take a 160 degree t stat bet you a million dollars

3 to 1 odds any takers

Man when are you guys going to learn - I am like EF Hutton when I speak everyone listen.

Engine serial number always needed, I preach that up here everyday. Follow my advice please and thank you.

click on the link for parts below - NOTICE 454 MAG CARB APP 1992 thru 1994 and then scroll down to T stat standard cooling . Notice it goes by serial number.

I have posted a bunch of times that since 1996 all marine carb engine went to 160 degree t stat.

1992 thru 1994 454 MAG CARB app - parts below.

Part number 5 - 160 degree t stat. so with that said what is your engine serial number once again

http://www.marineengine.com/parts/me...-thru-0f304999

BUP, you are, and I appreciate it like most others do.

No bet, lol.

I know a lot of the later model carb app's used 160 t stats. If I'm replacing one in someone elses motor I will go with what is called for. If someone puts in a 140, I will not worry about it.If it has any mods at all, I will usually recommend the 140F.

That said, personally, I have no issues with a 140F t-stat in a carbed application.

EFI, I will jump up and down with you. In fact, I may help you jump higher. LOL.

I hear you but for ME I have to follow OEM rec and specs - one is for warranty purposes and 2 for liability purposes plus class training we always brought up that temps are very important even for carb apps. Just saying. You know I have to bust on you a bit with the smack

It possibly came from the factory with a 140 t stat, which would make perfect sense of his gauge readings. But someone later on might have stopped at his local autozone & replaced it with the closest car stat they could get...the 160. My 1988 454 mag came with a 140. I'm running a crossover now & rarely see anything over 115-120. Happy boating!!

Thanks for the feedback and info guys.

I guess I better get my engine serial number to settle this debate eh? I wish we could accept bets...

I'm guessing from the other digging I've done, that this actually will be the 143 Tstat. The engine is referenced as the "454 magnum bravo" in other documentation I've read. The plate on the carb says 4600-5000 rpm range... if that helps.

Is the serial number you're referring to the same thing as the "casting number" that I would find somewhere on the block, or is that serial number on this carb hat plate as well?

Carb hat plate.

Get the 140F. :Smile:

I've got another can of worms to open...

So, lets say we discover the the OEM tstat IS 140/143. Even so, wouldn't the engine operate better and more efficient at 160?

Take into account these facts:
* it is a raw water cooling system, but It's never been in saltwater, and never will be
* It'll mostly always been in freshwater lakes in the northwest, purely fed by mountain and spring water
* "Warm" water around here is 70*. Parts of these lakes never get above 60.