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Reverse rotation engine fresh water pump connections reversed?
Posted: Wed Sep 16, 2015 12:39 pm
by boattown
I am rebuilding a pair Chrysler 318s and I did not take notice of the plumbing of the fresh water cooling system when I was disassembling the motors. Now that I am replacing all of the hoses, do I have to switch the inlet and outlet on the reverse rotation motor?
Both motors have non-directional pumps.
Re: Reverse rotation engine fresh water pump connections reversed?
Posted: Wed Sep 16, 2015 1:59 pm
by Joe
Hello, First the hoses are the same. The pumps are the same. One pump body will be 180 of the other. Look and see if the pump body doesn't show the direction of flow. Them figure out which way the belt is turning. I hope this make sense. The hose on the bottom is intake, the hoes on top is out put. Joe
Re: Reverse rotation engine fresh water pump connections reversed?
Posted: Wed Sep 16, 2015 11:01 pm
by boattown
I am not sure that is the case here. Here are photos of both the port and starboard engines I took before I disassembled everything and the orientation of the pumps are the same. Any ideas?
Re: Reverse rotation engine fresh water pump connections reversed?
Posted: Thu Sep 17, 2015 5:21 am
by Fastjeff
I'm gonna try to upload my sketch of which way everything goes. This site has tight restrictions on file size, so it might not work.
Here goes...
Jeff
Re: Reverse rotation engine fresh water pump connections reversed?
Posted: Thu Sep 17, 2015 10:43 pm
by boattown
This is a diagram of the raw water impellers, right? I am talking about the fresh water pumps bolted directly on the engine block.
Re: Reverse rotation engine fresh water pump connections reversed?
Posted: Fri Sep 18, 2015 6:25 am
by barkleydave
Yes. Hoses are not reversed. Direction of vanes are.
Follow Jeff diagram it is perfect.
Re: Reverse rotation engine fresh water pump connections reversed?
Posted: Fri Sep 18, 2015 9:45 am
by boattown
The fresh water pumps on marine engines are not directional (same pump for regular and reverse rotation motors). The vanes are straight. A car water pump is directional, though. See the images
Re: Reverse rotation engine fresh water pump connections reversed?
Posted: Fri Sep 18, 2015 5:34 pm
by TinLizzy
Although he says fresh water pump, I believe he is talking about his raw water pump. But as always, I could be wrong.