Originally Posted by lil red

Mike can you post a pic of it on the stand? Maybe there's something being overlooked or not thought of?

Originally Posted by the deep

Yep usually something stupid staring you right in face . Drink a beer and look at it with fresh eyes in the morning .

Originally Posted by US1 Fountain

Had very similar problem with my 502 when running a BM blower. Water in oil within minutes when ran in the lake. Block checked with torque plate, heads checked and resurfaced, still got water. Turned out when running on the hose at home, water pressure is almost non existent, so the issue never surfaced. But in the lake, pressure was there, especially when still cold and t-stat closed. Turned out the BM intake required more torque rounds to tighten down. Just the normal 2-3 rounds torqing the bolts down wasn't enough. Even after the 3rd round when the last bolt was torqued, the 1st ones where now finger loose. Water was simply blowing past the intake gaskets. Once I realized this, I just kept going around until the 1st bolt was holding torque. I believe it took close to 10x around the sequence to get the intake to pull down tight. The stock NA intake was never a problem. 2 rounds and it was tight. Don't know why. But it seemed motor temp and pressure were the 2 factors with mine. Water would blow past the gaskets at the lake, go home and test.... nothing. Possibly now that you are getting water after pulled, the intake gaskets have blown out. Check your intake bolts 1st thing, specifically the 1st ones in the torque sequence and see if they are still torqued.

Originally Posted by mike tkach

i built a na 516 cu in engine last year and it is putting water in the oil,before the build i had the block magged and it showed no cracks.dyno,d engine before installing it in the boat and was happy with the results,603 hp at 5500.i install it in the boat [24 sunsation] and it runs great but is getting water in the oil.this engine has brand new edelbrock aluminum marine heads .i removed the engine,tore it down to the bare block and had it and the heads pressure cheched,no leaks,at that time had the block and heads milled ,just a clean up cut to insure flatness.i put it on my runstand and ran it at 180 deg for 40 minutes with no water in the oil so i figure the problem is cured and i reinstall it in the boat,guess what,water in oil again.once again i remove the engine from the boat,remove the oil cooler and exhaust system and run it on my run stand,water in oil in 15 minutes.now i block off the thermostat opening,put 1 block off plate on 1 side of water pump hole and a - 8 fittind on the other,i put 35 lbs of air pressure on it for 30 minutes and no leak can be found.im at my wits end with this pos so im looking for ideas .the boat owner has been cool with all this but im starting to get pizzed about this mess.