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Raw water pump

J

jayhawk51

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I just bought a 89 Carver dual

I just bought a 89 Carver dual 350 and while inspecting noticed the hoses to and from the raw water pump are not installed the same on both engines. They are opposite each other. It appears to be the original install or at least been there for some time. Both engines crank the same direction. Any comments?
 
That's the question: Are t

That's the question: Are the motors rotating opposite to each other?

On mine (which they do) the hoses must go one differently or the pump doesn't pump.

Jeff
 
"Are you having a cooling issu

"Are you having a cooling issue or just curious?

Method used to establish engine rotation?

If they are factory installed pumps, the direction of rotation determines inlet and outlet. The pulley will rotate 'towards' the outlet of the pump and move 'away' from the inlet. If installed with the hoses reversed, the pump will not deliver sufficient cooling water."
 
"There is a cooling issue on t

"There is a cooling issue on the starboard engine. One of the exhaust elbows is badly cracked. Based on your description, it is also the pump that is reversed.It seems unbelievable that it could have been like that for so long. The engines have 350 hrs on them. I'm going to dbl check rotation tomorrow."
 
"The rotation is definitely op

"The rotation is definitely opposite what Mako states it should be, but it appears that the same amount of water is coming out of both exhausts."
 
"Then it's definitely pump

"Then it's definitely pumping water. When I, ah-hem, put mine on assbackwards it did not.

Jeff"
 
"Does it make a difference whi

"Does it make a difference which direction the raw cooling water passes thru the system? Will it just cool off the heated areas and the heat exchanger any way? OR IS that a critical function.

I think on one engine it goes to the transmission first and on the other, the u-cooler...I have not been to the boat in a few weeks so I did not really look but I am now wondering..."
 
"Raw water usually comes throu

"Raw water usually comes through the tranny cooler FIRST, then goes to the motor or heat exchanger.

Jeff"
 
"Al:

Like most things, the

"Al:

Like most things, the designer has choices to make. Like jeff noted, the usual result is the transmission oil is cooled first. second is usually the engine oil, followed by the HX, if present and ending with the exhaust.

Ken:

I'd suggest an extra set of hands or a remote stater switch to aid in a good inspection. The description as you have described it has something amiss.

On the elbow, if it is cracked, you shouldn't be running that engine...that's an excellent way to suffer the expense of water ingestion. It is quite possible the elbow cracked due to lack of water flow and the immediate cause was fixed and the crack not detected.

In terms of the water flow, you really need to measure it, not just look at it. The usual method is a bucket and a watch/time will 'seconds' display. the flow rate will vary with engine rpm.

Also, I didn't see where you mentioned if you had a closed cooling system or not. If closed, make sure the heat exchanger is full and the closed system has been purged of air."
 
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