water pump? chevy 350, 5.7 litre

I've got a 1990 Malibu, and I just got it out for the summer last weekend. I've never owned an inboard, and I didn't know about priming the water pump. I think I broke it or something, because after heating the engine up, we stopped it and found the water pump had a plug on the top apparently for priming. We primed it and it still won't pump any water. I'll probably have to get a new water pump, but I was wondering what the cylinder thing is that the water goes through before it gets to the pump. Is this a filter or something? I'm just wondering what other reason there could be before replacing the pump. Do they always need priming the first time out? Also does anyone know of a website where I could download some specs, or a manual for this engine?

thanks,
kal

Sounds like you have a faulty impeller. The pump should be self priming. The motor has two pumps. One is the impeller/pickup pump (follow the water line from the inlet, should be mounted to the front of the motor with a pulley or mounted in front of the crank depending on what style it is). The other is the circulation pump. If the impeller is burnt up it will overheat no matter what you do. The other pump shouldn't be damaged, unless it is leaking. The circulation pump is not serviceable. Check the archives about replacing the pickup pump impeller. It should be done more or less once per year, although I usually go two.

Check for any air leaks in your system. The top seal on my starainer/filter was damaged last year and air was being sucked in through there and stopping the system from priming.

sweet! thanks, you guys rock! I'll let you know what I find out.

Kal

I searched the archives for posts about replacing an impellor. I'm probably not searching right but I can't find anything... Does anyone know how hard and costly it will be to change my impellor? The intake water hose goes into the impellor shaft thing right? Do I have to replace the whole shaft? Any help would be great.

Also on a different topic, my exhaust has a hole in it, any ideas how to patch that?

There are two water pumps on boats, the raw water pump and the circulation pump. The circ pump is the one common to cars that is usually behind where a fan would be on a car. The raw water pump is what you are interested in. The pump will either be on the lower front side with a belt drive or directly coupled in front of the crank. On direct drives motors they are easy to change, I have done it at the lake in 20 minutes or less. The replacement impeller should be about $20 or so, maybe more if you buy it at the local marina.

Thanks Mikeski,

Any sugegestions where to purchase one?

www.Overtons.com