Out_The_Front

Thanks for all the input. I compression tested the engine right after putting the oil back in. I let each cylinder go about 6 or 7 cycles where they seemed to max out. All were between 150 and 160 psi. The boat seems to run very well and I did test drive it/go for a couple of pulls behind it before buying. This past weekend I ran the boat on the water with the doghouse off to make sure the fuel line and manifolds were holding okay. Once the engine was warmed up and we gave it some power, we started to see smoke billowing from around the exhaust manifolds. We weren’t sure if it was oil leaking from the valve covers or just the paint on the new exhaust manifolds smoldering from the heat (there’s no water jacket where they bolt to the heads. Anyways, it was only the paint but it drew our attention to the area while the boat was underway. That’s how we noticed the water weeping from the heads. Under further investigation, we saw that they only start to weep once you begin giving the boat power. At idle the leaking stops. I talked with the previous owner today and he swears up and down that he was unaware of the cracks before selling it to me. At this point, I'll give him the benefit of the doubt. I’m sure most people don’t study their engine at speed and I doubt we would have noticed if it wasn't for the smoking exhaust manifolds. He also says that he’s never seen milkiness in the oil so maybe they’re only external. Attached are a few pictures. The cracks in the head are just above the head bolts as @Jody_Seal and @lottawatta mentioned (There are a couple more than pictured). The crack on the block spans between two freeze plugs. It's partially hidden behind the engine mount and can only be seen looking back to front. Click here for Picture 1 Click here for Picture 2 Click here for Picture 3 Click here for Picture 4

Well, I bought a 93 Prostar 190 last fall from a member of this forum and just got it ready for the summer. Spent a lot of time/money installing a new Holley 4160, exhaust manifolds, and raw pump then took it out for a test drive this weekend with the engine cover off. To my dismay, I found that both heads started weeping water from cracks once the engine got above 1500 rpm or so. Then I noticed later today that there was a rusty linear feature on the block behind the engine mount terminating between two freeze plugs (probably another crack). When I bought the boat there were rust stains on either side of the heads/block but the cracks were not apparent because they were so small and I assumed it was probably water dripping from the manifolds because they were in rough shape. Wrong! Now that I've seen the water dripping from the heads, the leaks start exactly were the rust stains begin and correspond perfectly. After running it for about 15 minutes I brought it back in and immediately drained the oil. Luckily there were no signs of milkiness or water. Now that I’ve seen the water seeping out of the heads, the cracks are more apparent and it makes me sick every time I look at the boat. Based on the amount of rust, it must have been run for at least one summer after they cracked. I find it hard to believe that the previous owner didn’t know about the issue and if he had known, it was low of him to not own up to it. It was even endorsed by his ski partner who is rather active and well known member of the forum. However, perhaps they didn’t know and I should give them some benefit of the doubt. Anyways, moving forward I assume that I probably need to plan on repowering much sooner than I would have hoped. However, I’m not prepared to do so this summer and don’t want it to be a complete waste. Should I just slap some JB weld over the cracks and hope they are just external? Then wait for imminent failure. It looks as though they have been leaking for a while. Also, does anyone have any advice/experience with repowering? I assume that I might as well replace it with a remanufactured 351w since I already have a new carb, manifolds, and water pump for that setup. Any feedback is greatly appreciated. Thanks!