current setup in my boat is 1.25 hose from bravo xr its transom with sportmaster lower to sea strainer then to 2 stage hardin pump, with common outlet < Both stages exit into 1 1.25 hose> through oil coolers ect then to crossover out intake into headers and then overboard, i have a 1/2 line taped off the outlet of pump feeding intercooler and dumping overboard, the rear intake is plumbed into the rear of the header water manifold so they flow out headers

is the 2 stage pump too much for the single line through transom?

i cooked off 1 header last weekend had a water flow issue,header turned gold melted the exhast coupler at the transom ect, boat had 14 psi water pressure at 5200 rpm, im thinking theres a issue with a cmi header more than anything but have been curious about the setup. only had the boat out twice, thought about going to a transom pickup but dont want to slow the boat down with them

Mine is plumbed like this, 1.25 from the transom feeding the pump, then a -16 off the pump feeding the engine, headers, and a -12 from the pump feeding the intercooler and -12 dump over board, a pair of -4 off each side rear intake to a Y and dump over board,

you pulling from drive or transom pickup?

through the drive

single stage or 2 stage pump

2 stage, 1 -20 inlet and a -16 & -12 outlet........Edit: mine are plumbed through the strainer also

ok similar to mine except you have the stages exit separately and feed eng / intercooler sep.

what kind of pressure and temps you see

i was wondering if the 2 stage was too much to pull through the drive

my pressure is kind of low because Im dumping so much water, Im installing Imco lowers and from what Ive been told they will increase water flow over the XR lower, I can play with header restrictors and close down the intercooler dump if need be after I get to run the boat.

if you had 14 psi the whole time then you have enough flow in the system. if the drive was a restriction the pressure would drop off. I have had plenty of problems before with cmi headers getting hot spots, also with their tails. all it takes is for the inner and outer pipe to be a little too close and you get a steam pocket. as soon as that happens all flow thru that pipe stops.

Is this a closed coolant system?