Oil Temps
 

I have a 312 with 454 Mags. What is the safe oil temp range for them? I was cruising at 4,900 rpms and the oil temp kept rising and went past 230. I slowed to a 3,500 and they settled back down fast. The water temps were below 180.

You must have a blocked coolers- back flush them. BTW 4900 is not cruising- that is close to WOT. Max rpms I believe is 5000- 5400 range. Over 230 is getting up there.

Wannabe

The Full Throttle RPM Range of stock 454MAG's is 4600-5000, so I agree that 4900 is not cruising, that's about WOT.

230 is getting pretty hot. I don't like to see anything above 220, with 200-210 being ideal - Hot enough to boil away any trapped moisture, but still within safe territory.

230º is fine for oil. You want to see 210º - 220º all the time anyway to keep condensation from building up in the oil. 10º additional isnt going to hurt anything. I wish mine ran at 230º oil temps at WOT.

Now if it was 280º that is getting pretty hot but still acceptable for short WOT bursts with good modern oils.

You are 100% correct...

But I don't bother trying to convince anyone around here of that. :party-smiley-004:

your right on with that statement dude.mine runs 240 all the time and when i run her hard 250.it has been this way since i owned the boat.same motor for 6+years.i do use synthic oil.it keeps its color longer and withstands higer temps longer.

230 is great for oil!!!!! Get that water out of that oil nice!!!!!

First of all, oil temp is very important as well as to what oil you run. Yes some synthic oil does all a lower temp but AMSOIL will run even cooler. It is a proven fact that AMSOIL not only runs cooler but with less wear & tear on the engine. Just ask Bob Tegue. Mercury Racing division is always blown away with the lack of bluing on the internal engine parts. If interested in amsoil, email me at [email protected]... Buy at dealer price..

Thanks for the responses... Yes, I used the wrong term... 4,900 was WOT not cruising. I have been cruising at 3,500 and am seeing speeds about 40 MPH.

So... it seems that there are two opinions here. 1) 230 is too hot and 2) 230 is perfect. What would Merc say?

If I use synthetic, what is the recommendation for weight and brand?

I have been working on getting my oil temp up. Had way to much water under valve covers. Oil was only get like 200deg not good. Now I am 220-240 and she is very very happy!!!!! Running brad pinn oil.

Skydog

Wow, so far no ones asked where he's reading the temp from on the engine. makes a big difference IMO. I agree that 230 is not too hot.

220 is ideal when running long periods on high load, usually big diesels at load runs around 210 oil temps , gas engines can go a little higher but for shorter periods and more frequent oil change intervals. 230 is around there on the upper side of good in my book. I'd myself prefer it to be lowes.. around 210 as the only thing that separates from oil at those temps are water AND Especially the Additives. I used to support a guy in Key West that didn't listen to changing his oil when the temps went over 260 on the race... next race.. no more crankshaft...and yes it broke where GM V8's both usually do.. big or smallblock.. would he believe it was because he went over 6000 and the oil temps went skyhigh again.. nope... he blamed it on something else. Well I called the partnership quits after that. I'm too old and experienced in to hang around with stupid F-U's.

And it's almost the same where your oil temps sensor is if it's on the block or even the heads. If it's in the oil pan then there's some diference but not much to bother with.

230* is fine for running WOT. I would say perfect would be 220* at normal cruise speed and as long as stays below 260* on extended WOT runs. When it gets to 250-260, then you need to watch it closely to make sure it does not climb higher. Synthetics will not break down as fast from the heat and can handle the 260* temps for a longer period of time.

This is all assuming that the temp readings are being taken before the oil runs through the cooler and not right after.

Thanks. Now I would like a recommendation on oil. Brand and weight please.

Thanks

Where is the best place to have your sender?

Somewhere shortly before it reaches the oil cooler. That's where the oil will be it's hottest point, after it's run through the whole engine.

What I do for reading temp is get a infrared gun and shoot the oil pan when u happy with temp note what oil temp gauge reads. Done deal when my pan was reading 225 deg with gun my oil temp gauge was like 150deg. My sender is in the oil gale by oil filter.......... But all I need to know is 150deg on oil temp gauge on dash is right on the money.

Skydog

mobil one,20/50sae

20w 50 http://www.bradpennracing.com/

U are going to get a lot of options on this. Main thing change it and keep her full. But I love my bradpenn oil for sure!!!

Skydog

I've been running the Brad Penn since overhaul as well. Also run up to 250 degrees WOT at times. Both the engine builder and oil manufacturer don't have a problem with that temp.

Yes yes all happy!!!