Oil cooler
 

Will the oil cooler from a hp500 work on a 555ci motor?

Run it and see what you're oil temps are. I'm guessing no , but I'm no professional ,

Capacity of oil pan makes a difference in that question

I'm no expert, but anytime you start going above stock performance I'd suggest going with a bigger cooler with a thermostat and new lines. The stock stuff is barely adequate as is.

8 quart pan

Is anyone using a 2x18 cooler on a larger ci motor?

My Paul Pfaff 565's have 2" coolers on them, but my oil temp is a little higher than I like after a hard run. If I were doing it, I would upgrade to a 3" cooler with -10 or 12 lines. You won't be sorry

I would say no to cooler, lines, and adapters, very restrictive

I have you answer yesterday lol (3x18") good for 700 HP.

Just installed a 2x18 on my mine and it will not keep it cool. Have 5/8 fittings and lines and reaching 260 to 270 when running hard for short time (Won't run it long until I get the temps down), running 240 for just cruising. Will be installing a larger one soon

you reading before or after cooler?

Before the cooler

I would read after, you wanna know whats feeding bearings... I see 15-160 average after cooler, 190-220 MAX after a hard run, that's about 50 degree drop (normal) oil in pan 230-270 is not horrible before cooler... if you see 200 after that's 250 in pan if cooler is dropping the 50 ish that it should.

I would like to know what the after the cooler temps are, but guessing any cooler drops 50 degrees might be stretching it a bit. Sure glad I decided to change lines and cooler from original build. Just think if it hits 270+ now, it was roasting the oil with only a 12x2 inch cooler on it originally. Soon as my gauge gets to 160 my oil pressure goes from 80+ to between 72 to 75 psi (I think all good), it stays steady until around 240. When oil temp gets above 240 the pressure starts dropping below 70 and at 270 it falls a tad below 65 and this is where I let off the throttle.

When going to idle at 260, pressure is around the 25 psi area. As motor cools it comes back up to 45 when below 220

When I get my next cooler I might get another sender to install after the cooler, so I can move the wire over to see what the difference is

Before cooler is best to watch, its the real temp of the oil, And do you really know if and when your in bypass?. Cooler all Junked up all of a sudden. For watching both, 2 senders 1 gauge and a switch works. and no finding room in the Dash Panel

Didn't think of that, should have, that would be so easy

all marine engine builders I ever talked to said 50 degree drop is what it should be if cooler is proper size, mine is right there.. I have measured at pan and cold side to see.

my oil pressure goes to 25-30 at idle after a decent run that's plenty, it's 70+ anything over 2000 rpm, I am a fan of high pressure and shunned oil pumps .

Per Eddie young: I read the temp going into the engine. If you read it before the cooler, You are taking the cooler out of the equation. If you have a small cooler, the temps will be higher than if you have a large cooler. I want to know what the bearings are seeing. I don't want to see over 230-235 deg. That would put it near 300 before the cooler. A conventional oil will start to break down at much over that.


i asked to verify my thought process when I was doing my own engines guys said I was doing it wrong, I went with Eddies and my best buds advice with this

You think the oil coming out of the cooler doesn't instantly get hotter going through the pump and running through the crank ? you want to read the hottest oil. plain and simple. then you know for sure.

Not according to Eddie, Gellner, Ilmor and others I have talked to... all read AFTER cooler... I think they know a few things about marine engines..

Ok, you keep doing what your doing.

Come on, some reality has to come into play. Agree seeing what goes into the bearings is good to know, but if a great fitted cooler lowers the oil by 50 degrees, I wonder what a not so great cooler does? I had a 12x2 on the motor, and now I have a 18x2 and I'm hitting 270+ degrees. Sure wonder how hot the oil was getting with only a 12x2 cooler was doing because I was not letting off the throttle, because at the time I didn't know there was a problem? Include stock oil lines and fittings prior and who knows what was happening to the motor.

I will, been for 12 years with ZERO oiling issues... just sharing advice from the pros that I was advised....

BTW, Mercruiser reads AFTER COOLER ALSO... they would know nothing I assume... carry on.

I started with 2x18 and -12 lines and didn't like how hot it got even with 500hp and then went to a 3x18 with a thermostat that was a bitc* to plumb while in the boat. I wish I did it that way from scratch.

If you read at the pan, you have no idea what what your temps are feeding the bearings or any clue what your cooked temp is... that's why you read after....

I am looking into a high oil temp reading now myself. If I traced it out correctly, my Mercruiser is reading the temperature coming out of the block into the filter. From the filter, it goes into the cooler and out back into the block. Am I wrong?

We've been debating this before or after the cooler sensor placement for years here. My take on it is, it's good either way. Why? Because it means we are all watching our oil temps and adding larger coolers if things are getting into the cook zone! We're not being oblivious to what's going on inside the engine either way.

On my last boat with built engine, I had only one oil temp gauge, but installed 3 pole switch, and two sensors. One pre-cooler, one after. All I had to do was flip a toggle to see the temperature drop of the cooler.

I like your idea, now I have to figure out how to get a sensor after my cooler. I have a 2x15 cooler with -12 lines and my before filter temps get to 280 when running hard. But I run Amsoil 15w50 Dominator and 280 is within normal operating temp. Normal cruise speed I’m about 220-230.

Before cooler, just put on the filter housing

And what was the average temp difference? Thank you

Been a few years but around 100 degrees if I recall. Engine did have some oil control/windage issues with stock pan and ran higher oil temps than I would have liked, but it ran consistent none the less.