All great input. If you are going to run it and assuming you are not already running this oil, I would change out oil to rotella 15-40. This is a desiel oil but good for marine engines in my .02, particularly at breakin. If by chance you are running something like a 5w 30 synthetic now, you should get a better result with the rotella. I would try 4 qts total as a test.

Couple other thoughts; breather removed, how much air is coming out?
Do you smell burning oil? Windage problems will result in burnt oil smell due to splashing on the piston skirts.
And yes, I have had to wire my dipsticks in on new engines before so don't be shy about doing that. Just make sure you are getting ventilation out the breather.

BT

Likewise, I put Teagues on mine but tried to use automotive style beathers. These breathers only take a 3/8" hose instead of the 5/8" Merc uses for their breathers. Wasn't enough area in the small hose for the crankcase to vent through. Would idle fine. As soon as both engines were under load they began puking oil. Went to 2 push in "Mopar" style breathers with larger hose barbs so I could use larger breather hose. Problem solved.

Hahaha!!! You guys are giving me hope!! Maybe... just maybe... I wont have to pull this SOB back out and start all over. I am going to do a leak down test this weekend!!

If the leakdown test shows good just pull your breathers all the way out of the valve covers and take it for a short run with the engine hatch up/off. If it doesn't push the sticks out then, you will know there is some type of restriction in the breathers. Do the breathers you are using have the filter material in them? Do your valve covers have baffles in them? If there is filter media in the breathers and the valve covers do not have internal baffles, the filter media in the breathers will quickly become soaked with oil which then restricts the engine's ability to breath. Capiche?

I hope that is your problem and that you don't have internal issues. Always look to the simple things first.

HAHAHA IT WORKED!!!! Did a leak down and no significant leak on any pistons... I installed a PCV check valve and the engine completely changed its behavior! Too 1/2 quart of oil out and took her to the lake... WOW that boat runs!! Thanks everyone for the help and support!!!!!!

Good to hear Longrange..we need running pics/vid now!

I am going to detail her and put all the interior back together... As soon as she is done... I will post up pics and vid!

OUTSTANDING! There is nothing worse than putting so much work, time and money into something only to find out that you have to start over. I am glad that it worked out for you.

Rene

That is great to hear. Glad it all worked out!

Again... you guys are awesome!!! Thank you so much for all the help... at some level OSO has helped me with every step of my boat!

My hydro steering...
My New engine...
My trim tabs..
Outdrive removal and install...
Everything... you guys are all great!!!

Now I just have clean up to do... my Tach isnt reading right... I can hit the rev limiter (set to 5k right now) but the tac only reads 3100 RPM. Temp gauge is not reading above 100 except rarely... Have a bit of a leak on the hydro steering fittings... and I need to figure out how to use my tabs.

Well with a ~500HP engine... and a Mirage 25p prop... it feels like it still has more in her if I play with the pitch some. Do you guys use your tabs at speed?