I have been nursing my 1985 Sea Ray through the trials of advancing age (both me and the Boat) and have recently experienced a strange seizing of the engine. The problem started about a month ago when the engine suddenly died with a coughing sound that I could not identify as either backfire or post ignition in the exhaust but definitely burning in the wrong place. The engine restarted quickly and thinking that it was maybe a bit of water in the gas, I replaced the water separator and added some dry gas to the tank and it was fine for some time. The incident repeated after a couple of weeks so I returned immediately to my dock and made arrangements to take it out of the water for the season.
As I started it up to get it on the trailer the engine started to die and it backfired through the Carburetor and died. When I tried to restart it the engine seized and would no longer turn over. I rather assumed that either I dropped a valve or broke the timing chain and jammed a piston into a valve. I removed the covers and found the valves seemingly in good order; no dropped valve, no broken valve spring, stuck valve, loose pushrod (which might indicate a collapsed lifter or bent pushrod) and no other obvious valve train problem.
I then removed the front cover and found a significant slack in the timing chain. I removed the exhaust manifolds and then the spark plugs which all seemed in good shape. When I removed the plugs in cylinders 1 and 2 several ounces of what I think was water drained from each cylinder. I turned the engine over several times to observe valve action; which appeared normal at that time. In preparing to replace the timing chain I tried to turn the engine to align the camshaft timing dot with the crankshaft dot and it would no longer advance and is now still seized.
I had planned my next move to remove and inspect the heads for an eyeball examination of the pistons to assess any damage that might seize the engine but I had a thought that stopped the tear down. I see no apparent reason for the seizure in the top or front of the engine and therefore wonder if there is a possibility that the Alpha 1 stern drive might be itself seized and not allowing the engine to turn over. I have not yet checked the gear oil in the drive nor have I removed it but I think that is my next move.
Any insight into possible causes of this problem will be most appreciated.
Thanks in advance, Jim
As I started it up to get it on the trailer the engine started to die and it backfired through the Carburetor and died. When I tried to restart it the engine seized and would no longer turn over. I rather assumed that either I dropped a valve or broke the timing chain and jammed a piston into a valve. I removed the covers and found the valves seemingly in good order; no dropped valve, no broken valve spring, stuck valve, loose pushrod (which might indicate a collapsed lifter or bent pushrod) and no other obvious valve train problem.
I then removed the front cover and found a significant slack in the timing chain. I removed the exhaust manifolds and then the spark plugs which all seemed in good shape. When I removed the plugs in cylinders 1 and 2 several ounces of what I think was water drained from each cylinder. I turned the engine over several times to observe valve action; which appeared normal at that time. In preparing to replace the timing chain I tried to turn the engine to align the camshaft timing dot with the crankshaft dot and it would no longer advance and is now still seized.
I had planned my next move to remove and inspect the heads for an eyeball examination of the pistons to assess any damage that might seize the engine but I had a thought that stopped the tear down. I see no apparent reason for the seizure in the top or front of the engine and therefore wonder if there is a possibility that the Alpha 1 stern drive might be itself seized and not allowing the engine to turn over. I have not yet checked the gear oil in the drive nor have I removed it but I think that is my next move.
Any insight into possible causes of this problem will be most appreciated.
Thanks in advance, Jim
