I bought a 1996 VIP Valiant 4.3 as a project boat that had not been run in several years. It turned out the block and heads
were cracked so I replaced the engine and reused the old intake and exhaust manifolds. On initial start up both
manifolds got so hot they melted the flapper valves and exhaust bellows. I then did some research and decided to remove the outdrive to check the impeller in that. I have not had to time to pull it apart but I did stick a garden hose in the fresh water port and started it again. This time It runs for about 5 minutes and then one exhaust manifold stays at 90degrees while they other one slowly creeps up to 190degrees. I notice that when it starts heating up I have less water flow out the exhaust port then the side that is staying cooler. I'm thinking that I need new manifolds but want to make sure its not a water pressure issue from using a garden hose as opposed to the outdrive impeller pumping water.
I have also removed the suspect manifold and ran water through it and it appears to flow pretty good while at room temp. I'm guessing maybe when it gets hot its expanding and slowing the flow?
I have the old one piece manifolds and dont really want to put another $800 in this project if i dont have too.. Does anyone have any suggestions for a good place to get one replacement or a cheaper kit for the newer 2 peice and elbows?
were cracked so I replaced the engine and reused the old intake and exhaust manifolds. On initial start up both
manifolds got so hot they melted the flapper valves and exhaust bellows. I then did some research and decided to remove the outdrive to check the impeller in that. I have not had to time to pull it apart but I did stick a garden hose in the fresh water port and started it again. This time It runs for about 5 minutes and then one exhaust manifold stays at 90degrees while they other one slowly creeps up to 190degrees. I notice that when it starts heating up I have less water flow out the exhaust port then the side that is staying cooler. I'm thinking that I need new manifolds but want to make sure its not a water pressure issue from using a garden hose as opposed to the outdrive impeller pumping water.
I have also removed the suspect manifold and ran water through it and it appears to flow pretty good while at room temp. I'm guessing maybe when it gets hot its expanding and slowing the flow?
I have the old one piece manifolds and dont really want to put another $800 in this project if i dont have too.. Does anyone have any suggestions for a good place to get one replacement or a cheaper kit for the newer 2 peice and elbows?
