a good flush for the oil cooler is a high volume water pump and 5 gallons of diesel fuel and a Large oil filter to filter the oil going INTO the pump and just circulate it to the 5 gallon bucket of fuel. When you believe You have it all out then hit it with new fresh fuel and a new filter.

Thanks for the info guys. While I've got your attention. I need some help. These motors were 330hp last year. The only thing that remains is the bare heads and the blocks. I didn't add oil coolers. I was gonna do that when I put these in my other boat. I need to upgrade the oiling system. Dry sump I think is a little much for me now. What do yall recommend for oil coolers?

How big an oil pan are you guys running?

I'm running 12" Mercury Racing on both of my 355 Vortecs...they ran too cold (140* in 85* water so I had to put oil thermostats inline to get the operating temp up to 165~175*. They should work well for you....I think they were an over kill for me.

Thank you sprink58. I'll check into those.looks like what I need.
I finally got the engine taken apart tonight. I spun two main bearings pretty good, and got the other three hot. The rod bearings are fine, as well as the cam bearings and everything else as far as I can tell. I'll be running it over to the machine shop in the morning.

Soo.. I'm thinking oil coolers and 10 quart pans?

This is a pretty nice 10qt. pan. The one in the link is for a Mark IV.
http://www.jegs.com/i/Milodon/697/31557/10002/-1

You can get a decent cooler here. Just pick out the one you need.http://www.hardin-marine.com/c-731-t...l-coolers.aspx

So in doing a "Post Mortem" on this poor motor...what do you think happened to allow it to spin the Main Bearings ? I wonder if it quit oiling and if so why ? I also think about structural flex in the block that set up an oscillation in the crank causing a separation in the main bearing caps. Once just one cap allowed the bearing to spin...it stopped up an oil passage and/or allowed that rear main seal to blow out causing a fatal loss of oil pressure.

The "Metallurgist" side of my brain suggest that your machine shop "Hot Tank and then Magnaflux the lower end to check for cracks that would allow this to happen.

Sort of takes me back to my days in the UA Destructive Testing and Materials Forensics Lab at Tuscaloosa !! LOL

Good luck with this and let us know.

I got some coolers I would be willing to sell if interested, fresh water only, used for 2 years. I swapped them out because I replumbed my engines/trannies and it made sense to go with a different cooler for fitment!

I got the block and crank down to a shop in birmingham with an align boring machine on wednesday morning. Sprink, you're hurting my head with all this block flex magnaflux fancy schmancy talk. I think I either blew out the rear seal with too much crankcase pressure or I lost oil over the back of the black/intake joint. I always make that out of RTV. With the air gap edelbrock intakes it didn't take muck rtv, like near 1/8", with the blower intakes, it seems closer to 3/8". I think because of the thickness off the intake gaskets. I noticed when pulling the right motor apart, my bead wasn't quite touching in a few places in the rear. Which at high rpms would sling oil up there pretty good. So maybe that's where my oil went instead of too much crankcase pressure. That's what I'm hoping.

I've got some Milodon 31557 10 quart pans here now. I'm gonna pull the left side motor and replace the oil pan on it now also. I'm supposed to get my right motor back on wednesday so the race is on to get it together and meet the family in Gulf Shores next weekend. Now I've got to muster up the motivation to get out there and do some sweating.

Jim I may be in the market for your oil coolers. I think I'll address that in the off season. I do appreciate the offer.