seamate

I am just finishing up my winter project of building a fresh healthy 502 for my Checkmate. The engine is on a stand ready for paint. My intention is to spot prime bare spots with zinc chromate from a can then finish with Imron. Any comments pro or con? What paints do others recommend?
Thanx, Dave

convincor

I'll be doing the same thing i'm just further behind. I'll just see what feed back you get.
What did you do to your 502?
I've got a 90 convincor gtx that the 502 will be going in.
Have you run this engine before?

seamate

convincor
I have a '95 502 EFI, which I bought all apart with one scored cylinder. I sleeved the cylinder back to stock bore and replaced the piston and completely rebuilt the rest of the engine with bearings, rings, stainless severe duty valves, springs, roller rockers, fresh cam and lifters. I also have an M-1 Procharger and Stainless Marine exhaust. The last thing I added was dual ram full hydraulic steering. All of this is going in my '89 Convincor.
Dave

convincor

My first mission this winter was the steering. Hated the way it steered Put a full dual ram system together with parts from all over the country. Lots of research, and help from OSO members, but did it for about $1600. The only used parts are the rams. Bought a brand new drive and just picked up a 03' transom assembly. picked up Gil risers of 500hp for $300 and manifolds for $750. The 502 is next. A neighbor has it. Getting the long block from him then i think that I'm going to add a roller cam, air gap intake and a 800 holley. Has been recently rebuilt. Will still go though it and do bearings and oil pump,chain..
What prop are you using???
P.S. sorry to get off you original subject.

seamate

Convincor,
When I got my Convincor, about 3 years ago, it had a 454 Mag w/ Bravo drive. The prop was a 3 blade of unknown pitch and diameter. I found that I couldn't trim the drive at all. When I trimmed the least bit off of full in, the prop would blow out. Then I bought a Bravo one 4 blade, 24" pitch. It is bigger in diameter then my first prop and really has some bite. I could trim it very effectively, however, it was probably 2" too steep for the stock 454 Mag, 365 hp, as I could only get about 4400 rpm. Now I have built this fresh engine which should dyno in at around 650 hp. I believe that I will need about 30" pitch but will borrow some props from friends before I but another. By the way, I fairly recently discovered this website and have found it to be a great resource. It's cool to find that there are as many other crazy people out there as I am. I look forward to hooking up with some of these guys when the weather finally breaks!

Dave

convincor

I think I'll only be at around 500hp. Let me know what you end up with for a prop. I've got a 23p Mirage plus on now but that won't work with the 502.
Where are you???

seamate

Convincor

I live in Southeastern PA and generally boat in South NJ and the Chesapeake

seamate

Back to my original topic. Does anyone have any input re: engine paint?

Brad Perry

Sounds like you have it. I just scotch brited the heck out of the factory merc coating and wiped it down real good with laquer thinner to remove any gloss on spots-corners I couldn't reach. I didn't treat the bare metal, but there wasn't much. I would be more concerned about a reasonably smooth finish, than bare metal. PPG epoxy primer will cover a lot of the porosity of a bare block and not dissapear when sanded. The life of a marine engine block (coating wise) is pretty easy. I used a two part urethane (concept).

RLW

Seamate, did you use Inconel exhaust valves?
It is important. I have seen two separate failures due to using the wrong exhaust valve material in a friends engine.