Re: Water Intake... STUMPED
Thanks Don.
Already have a service manual, but its good to have the online copy to reference.
The water tube is connected. The key is in the impeller. The shaft will turn (I can start the motor up, put it in drive, and propeller spins fine). I was also able to turn the shaft by hand before i returned it to the upper housing, and yes, the impeller was providing resistance.
I'm going to disconnected the hose at the PS cooler and insert some form of wire back through the transom to make sure it is all clear. Perhaps the water I was pumping through it earlier had enough pressure to get by, whereas the pressure from the impeller doesn't. I also shot water up through the water tube with the lower unit removed and it made it up through the hose to the engine.
I am not entirely sure of when the impeller went bad. The boat was purchased used and the previous owner said he replaced the impeller, but the boat was still overheating. Later the next day after purchasing, my brother fired the boat up in the driveway for about 10-15 seconds without water. After yelling him to cut it, I was concerned the impeller was toast. I was doing a lot of engine tuning previously, and wasn't concerned with the pump. I have the engine running near flawlessly, but realized it was getting pretty hot awefully fast during the testing. I checked the thermostat, and it was fine. I had also previously flushed the block and exhaust manifolds, so they were clear. I then removed the intake hose from the thermostat housing and found no water to be pumping. I should have thought to replace the impeller immediately when it was started without water, but I was more concerned with the engine performance, and the brief periods I started the engine didn't heat it up, plus I had the block filled with water.
I do not know if the damage was caused by my brother or the previous owner. When I removed the lower unit, the impeller was mangled and the blade tips were gone. There was also obvious melting damage on the pump insert (solidified plastic on the walls). I found a few pieces of the blades in the intake. I wouldn't assume that the other pieces were sent up the pipe, but I guess it is possible.
Anyways, I'll double check the whole unit when I get home tonight and give an update. Like I said, I'm hoping for a stupid mistake I made somewhere along the line. I did the repair work at night on my porch, so I guess anything is possible (P.S., I hate this daylight savings stuff). Thanks for the input guys.
Brief history of the boat:
I purchased the boat with the intent of knowing it needed work. We paid 2k for the boat because the hull and interior were in great condition, the oil pressure was excellent, and the engine ran ok despite rocking and being reportedly "under powered." My brother and I purchased the boat together, and both being mediocre mechanics and engineers, decided we could work it out. The engine rocking problem was pretty quickly identified (thanks to the forum) as being improper firing order as the 3rd and 4th cylinders were not firing. After correcting that, I was still not getting any power out of the 3rd cylinder, although testing gave me a very very small spark. Replacing the spark plugs didn't help, so I went to the distributor cap. The cap appeared pretty clean, but the 3rd post was slightly off-kilt. I replaced the cap and the distributor rotor components. The spark was slightly better. I then adjusted the breaker point and the engine is firing like a champ. Amazing.
After I got the engine working, I was letting it run for a while to prepare it for an oil change. The temperature was getting pretty high, so I turned it off and let it cool. This is when I checked the thermostat and noted it was fine. Starting it up later is when I noticed there wasn't any water coming up from the lower unit, which is where I'm at now. Was hoping to give it a good test run this weekend, as my brother from the north is coming over with my other brother and his wife. Hopefully can get it worked out.
