RickR

What would be the best size oil cooler (wo/thermostat) for a 22' V hull w/ HP 500 clone.
Majority of boating in summer with water temps between 75 and 90 degrees.

Currently I see oil temps around 220 when cruising below 3000 RPMs but temp rises quickly to above 280 at WOT using a 454 Mag stock oil cooler (combo unit oil cooler 9"x2" , power steering cooler 3" x 2")
THANKS!

RLW

Rick,
I would think the HP500 oil cooler with Oil T-stat filter mount and a separate PS cooler would work well. I think the oil cooler is around 2"x17" in size.
This setup, I use, on a 540/9.2:1 CR motor. Oil temp is 220F at cruise and gets to 250F on hard runs. I know a longer cooler is available for the 540 Bulldog and think that it would keep my WOT oil temps lower. I run synthetic so the 250F oil temp is not much of a concern. Plus, those WOT runs are far and few between.
Russ

ratman

i have some used oil coolers, that dont have much usage. ratman

RLW

Ratman,
What size coolers?

PatriYacht

No way, that's too hot! A steady 220 would be a lot better. I'm using Eddie Marine 3 x 18 coolers on 540's and I can run poker runs at a steady 45-5000 rpm and the oil stays at 220-230.

blue thunder

I wiped the mains out on my sb engine last year running dino oil at 280f as measure before the cooler. 280 is way to hot for dino oil, and synthetic can only take it for a short while. I rebuilt that engine and switched to synthetic mobil 1 in both engines for the balance of that season. The bearings in both engines were showing signifant wear at the end of that season even though I ran synthetic. 280f is too hot. I changed to eddie marine 3x18 coolers and got somewhat lower temps. Blocked bypass, little change. The biggest impact to reduced temps came when I switched engine coolant tstat to 120f from 160f. Now I run around 200-210cruise and 230 max after long wot blasts. As far as sizing a cooler, bigger is better in my opinion. You can always add a tstat if necessary.

BT

RickR

Thanks for the replies
The sender is in the oil pan and the temps rise ABOVE 280, which I feel is too hot even for synthetic oil.
Cast iron heads w/9.4 to 1 compression.

I'd like to keep WOT oil temps below 250 so I think I'll look for a combo unit with the oil cooler side around 15X3".

WETTE VETTE

I went with a huge oil cooler from CP Perf. designed for 1000+ HP and has a t-stat built in. I am running a lot less than 1000 HP and the oil temps are perfect. At a slow cruise they get to 160 to 180 in the pan, an aggressive cruise they get to 200 in the pan. At a high speed cruise or at WOT they get to 220 pretty quick and stay there. After some really long WOT passes the most I have ever seen is 230 in the pan. I feel over-sizing the cooler and running a t-stat is the best way to go!! Good luck!

Craig

MACDAD260

Revolution Marine has a nice looking cooler at a good price. http://www.revolutionmarine.com/

PatriYacht

I also use a thermostat. I think that accounts for the steady temps.