I hope to get my Donzi project in the water on Monday and wondering about how to run the new 502 for a good break-in?
Right now, motor has about 2 hours run time, on a stand, varying engine speed from 1,200- 3,000 with most of the run time around 2,000RPM..... I had some reversion issues and got it worked out and had some water in the oil so it was changed out twice with new filter each time. Oil is fresh Rotella 15w-40 9 quarts total. I do have a wideband monitor to check my afr's and wil will be tuning the mighty demon 850 on the water. I don't think I will do any full throttle for at least 10 hours and I want to see what is a good procedure to follow?

Being you already have 2 hours on engine, but had a issue with water isn't the best way to start. My concern would be; how long water sat in cylinders and corroded the rings into the ring lang of the piston. If you have any stuck rings YOU WILL HAVE PROBLEMS. Water that gets into a cylinder and is not addressed immediately and sits and you free the engine up is going to be a problem. Unless you tore the pistons out and inspected them. Hopefully; that's what you did.
Breaking an engine in. Well on the dyno; it's warm it up, set timing, adjust fuel levels in carbs. Start with a mild load on engine and load the engine varying the RPMS, once thats done; I let the engine cool down. Check valves, relash either hydraulic or solid and start over with the warm up, then go into stepped pulls, checking all data, then once that is complete and all is safe for full pulls. This doesn't happen after 10 hrs of run time, once everything is checking out 100% on dyno and once in boat 10 hrs is not anything except giving someone 10 hrs to see if the thing is going to come apart.
Testing your engine in the boat is an uncontrolled testing cell, by the time you see something in the boat;; it's to late. Unless you run with the hatch off, someone looking at the engine and someone watching instruments while you drive or someone else.

My 598 was broken in while idling out past the no wake. After that it was W.O.T. And not much less. I did stop a few times to make sure I didn't have any leaks and oil level was good then back to wide open. I was always told you break them in how your gonna drive them and that is how I've always done it.

around here that 1500 in dyno time for a 4k motor?

run it like you stole it,thats how i do it!

tpabayflyer - I got a question well maybe 2. How did you detect it was reversion and how did you fix it? I just started mine up for the first time and my oil turned a little milky. I'm just trying to figure out what's my next move in trying to fix it.
Thanks

Capt Jack , this thread may hold some of the information you seek . http://www.offshoreonly.com/forums/g...w-build-4.html

Thanks fellas, fortunately I was able to catch the reversion pretty fast....... I discovered the water when my O2 sensor failed out...... I removed the sensor and it was wet? Took a manifold off and water in all the exhaust ports.... Same on the other side.... Oil was a little milky so I changed it out and removed all spark plugs and squirted oil in the cylinders and spun it over...... Everything looks fine and I was lucky to catch it right away........ I am using Aluminum 496 exhaust and did not use the turbulators. I also had the standard low risers as well. I changed out to a set of 2" taller risers and put the turbulators back in and all is good. Ran the engine for another hour and changed the oil and filter one more time and all is well. I had to glass and redrill the thru-hull exhaust in the Donzi and move them up 4"....... The riser are very tall and sitting on a 1" spacer as well. I polished them up to a nice shine and they look pretty cool!! They have a nice slope down from the top of the risers to the exhaust outlet.

Cpt Jack, what kind of exhaust are you using? Any cam more than 230* duration @.050 gets dicey for reversion depending on what you are using..... Lots of variables with the whole reversion issue....... I guess I don't have to worry to much about the break in process after all? I will still take it easy for a bit while I get my AFR's jetted properly.......

I was going to suggest my other thread if Cpt Jack happens to be using the 496 Style exhaust....has anybody seen the new Merc 520 engine? It uses the 496 exhaust with the tall risers........

http://speedonthewater.com/new-boats...new-520-engine

As previously mentioned if you had any reversion issues get the oil changed quick and get everything coated with fresh oil..... this picture was taken after a 1 hour run and look at how the moisture built up on everything?? it was only sitting for an hour after running and when I removed the manifolds and valve covers off this is what I saw......the tops of the valve covers had a bunch of fresh water drops from condensation......... reversion is definately bad news and will kill your engine quick. don't let that moisture sit in the engine....... TBF