I bought a 97 Bravo with a 2 year old 4.3 Volvo Penta inboard. First time in the water it had no power and the gray sludge in the oil from water. (I had fresh oil in it). I figured blown head gasket but found a stuck valve and bent pushrod. The gasket was good but it seemed like the bolts came out so easy I figured that’s where my leak was. I had the head pressure tested, resurfaced, valves ground and magnafluxed. I bought new head bolts. I put it back in the water and it ran great for about 10 min when I noticed steam coming from the vent tubes again. My compression is 180 +/- 5 psi. I’ve blocked all the hoses and put about 25 psi in the cooling system, no leaks and holds pressure. I made a block off plate for the exhaust and put 60 psi, no leak. We inspected the cylinders when the heads were off. The only thing I’ve found is the mating surfaces between the exhaust and the riser had a few thousandths difference. I would think the gasket would still seal this.
Im at a loss as to where to look next. I’ve run it on the hose over an hour with no problems. I’m open to try any suggestions.
Im at a loss as to where to look next. I’ve run it on the hose over an hour with no problems. I’m open to try any suggestions.
