I've just rebuilt my Merc. 470. Dropped it in and cranked it, (didn't run it). I noticed that I'm getting compression in the coolant. Easy, right? Pulled out the plugs and pressure tested the cooling system. Coolant leaked into #1 and #4 cylinders. It also wicked out the front of the head gasket near the front cooling passage. I pulled the head off and checked the gasket, block, and head for straightness, imperfections, and so on... I had the machinist come by and look at it. He said that there wasn't a lot of "crush" to the gasket. I checked the deck of the block and it seems that the cylinders are all .003" below the rest of the deck. I figured that the gasket should compensate for this and it shouldn't be an issue. The engine is .030 over, new pistons, rings, bearings, gaskets, valve job, decked head (just to make sure it's straight), and so on. So, what's going on? I torqued the head per Merc. instructions:
50-90-130 ft./lbs. I wire-wheeled the head bolts clean and dabbed oil on the threads before torquing them. I reassembled the motor and same thing! I haven't run the engine up to operating temperature yet. I don't have the outdrive on and I don't want to put it on unless I'm sure that the motor is staying in. Do I need to run it and retorque it to get rid of the problem? Should I pull the engine and drop it off at the machinist and tell him to deck the block? Any ideas?
50-90-130 ft./lbs. I wire-wheeled the head bolts clean and dabbed oil on the threads before torquing them. I reassembled the motor and same thing! I haven't run the engine up to operating temperature yet. I don't have the outdrive on and I don't want to put it on unless I'm sure that the motor is staying in. Do I need to run it and retorque it to get rid of the problem? Should I pull the engine and drop it off at the machinist and tell him to deck the block? Any ideas?