closed cooled ?
08-25-2009, 10:23 PM
#2
Chris
Gold Member
On the 525 motor, some restriction is needed on the starbord collector to equalize water flow from the heat exchanger, and keep the headers on both sides aproximately the same temperature. On this motor, I think they are restricted too much.
On the 600sci and 700sci, the tailpipes are restricted to force water thru the whipple type innercooler.
I personally think that there needs to be more water flow to the 600 and 700 motors. There are lots of people that have had smartcraft water pressure issues because of merc's water setup on these motors. These proplems are usually solved by installing a seperate water pickup and strainer for the innercooler, then opening up the restrictors in the tailpipes.
Chris
On the 600sci and 700sci, the tailpipes are restricted to force water thru the whipple type innercooler.
I personally think that there needs to be more water flow to the 600 and 700 motors. There are lots of people that have had smartcraft water pressure issues because of merc's water setup on these motors. These proplems are usually solved by installing a seperate water pickup and strainer for the innercooler, then opening up the restrictors in the tailpipes.
Chris
Last edited by CB-BLR; 08-25-2009 at 10:28 PM.
08-25-2009, 10:27 PM
#3
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08-25-2009, 10:37 PM
#4
Chris
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Do you mean resonators inside the exhaust hose by the tail pipe? http://www.boatfix.com/merc/Bullet/00/00_13.pdf
http://www.mercruiserparts.com/Show_...lpipe+Assembly
Chris
08-26-2009, 06:21 AM
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On the 525 motor, some restriction is needed on the starbord collector to equalize water flow from the heat exchanger, and keep the headers on both sides aproximately the same temperature. On this motor, I think they are restricted too much.
On the 600sci and 700sci, the tailpipes are restricted to force water thru the whipple type innercooler.
I personally think that there needs to be more water flow to the 600 and 700 motors. There are lots of people that have had smartcraft water pressure issues because of merc's water setup on these motors. These proplems are usually solved by installing a seperate water pickup and strainer for the innercooler, then opening up the restrictors in the tailpipes.
Chris
On the 600sci and 700sci, the tailpipes are restricted to force water thru the whipple type innercooler.
I personally think that there needs to be more water flow to the 600 and 700 motors. There are lots of people that have had smartcraft water pressure issues because of merc's water setup on these motors. These proplems are usually solved by installing a seperate water pickup and strainer for the innercooler, then opening up the restrictors in the tailpipes.
Chris
Last edited by crayolacrazy; 08-26-2009 at 06:24 AM.
08-26-2009, 08:51 AM
#6
You should be using the drives for the engine water and use the transom pick ups for the intercoolers. That is how I run it and I have no issues at all.
When you are in 1-2 waves, you are introducing air into the system because there is not a consistant flow of water to the pickups on the transom.
When you are in 1-2 waves, you are introducing air into the system because there is not a consistant flow of water to the pickups on the transom.
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08-26-2009, 09:31 AM
#7
Chris
Gold Member
Smitty is correct.
You should have the drives feeding the engines, and the pickups feeding the innercoolers. On a closed cooled motors, mercury racing suggests 30-50 psi as normal running water pressure at wot.
On a smartcraft equiped motor, if water pressure drops below 26psi, with the motor above 5200rpm, the computer will throw a fault code. If the water pressure drops below 21psi with the motor above 5200, the motor goes into guardian mode, and will reduce power.
Remember... on closed cooled motors, the engine is not seeing any water pressure from external sources. Water flow is regulated by the restrictors in the tailpipes, and/or the restriction in the innercooler. The block is running antifreeze, and the only pressure on it is caused by the circulating pump, on the front of the motor.
Chris
P.S. I typically have water pressure in the mid 40's at wot.
You should have the drives feeding the engines, and the pickups feeding the innercoolers. On a closed cooled motors, mercury racing suggests 30-50 psi as normal running water pressure at wot.
On a smartcraft equiped motor, if water pressure drops below 26psi, with the motor above 5200rpm, the computer will throw a fault code. If the water pressure drops below 21psi with the motor above 5200, the motor goes into guardian mode, and will reduce power.
Remember... on closed cooled motors, the engine is not seeing any water pressure from external sources. Water flow is regulated by the restrictors in the tailpipes, and/or the restriction in the innercooler. The block is running antifreeze, and the only pressure on it is caused by the circulating pump, on the front of the motor.
Chris
P.S. I typically have water pressure in the mid 40's at wot.
Last edited by CB-BLR; 08-26-2009 at 09:52 AM.
08-26-2009, 07:45 PM
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You should be using the drives for the engine water and use the transom pick ups for the intercoolers. That is how I run it and I have no issues at all.
When you are in 1-2 waves, you are introducing air into the system because there is not a consistant flow of water to the pickups on the transom.
When you are in 1-2 waves, you are introducing air into the system because there is not a consistant flow of water to the pickups on the transom.
08-27-2009, 06:08 PM
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I have cmi headers ,install 2 years ago could never touch them ,also have 5 inch heat exchanger so this year we added the pickups thinking that it will run nice and cool come to realize that the headers didnt have any restricters I looked at all mecurys closed cooled motors so I added some ,still messing around with pressures now I can touch my headers also I have gauge set up too . I do think I needed the restricters allalong Ill be testing this week end and lowering the scoops
Last edited by crayolacrazy; 08-27-2009 at 06:10 PM.
