Running Hot-Help, I need to fix this tomorrow morning!
 

Memorial Day weekend we drifted into shallow water and sucked up some sand. Stupid f-ing nose cone on the bravo with a low water pick-up acts like a vacuum cleaner on the bottom. It looked like it went through the strainer and clogged the outlet of the strainer which is the intake hose to the sea water pump. Needless to say it burnt the impeller up.
I changed the water pump on the river with a used pump I had in the v-berth but didn't flush the coolant lines and oil coolers. It ran hot soon after I got on plane and I realized that there was probably junk in the oil cooler. I was close to home so we idled it back.
Last Sunday I took the outlet off the sea pump and the inlet off the t-stat housing and ran the garden hose through it to back flush….clean water came out. Then blew compressed air through it and got some sand and impeller junk. Did that a few times and it was all clean. Took it to the river and it was fine heading out 150*. Then it went to 155* and 160*. Normally gauge is always dead on 150*. On the way back in it was 150-155 til I came off plane. Started climbing up to 180 at idle. Raised the throttle to 1200 and the temp came back down. Put it on the trailer....
Today I replaced the sea pump thinking the one I put on it was old. Back flushed again-nothing came out. Pulled plugs on block and clear water came out. Took it to the river and it was 145* idling out for about 10 minutes. Got on plane and it went to 150* and stayed there for a minute or two. Then I.... not 100% sure but... I think I heard the exhaust change tone very slightly. Soon after that the temp started going up, went to 180* Came off plane and there seemed to be plenty of water flow from the exhaust but the temp stayed at 180-190*. Shut it off and took the t-stat housing off and the t-stat was wide open like it should be. Took t-stat out anyway and went back home. Temp stayed 180-190*
What do you think? Still impeller trash blocking? Maybe I flush it and it moves the piece, then when I go to the river it moves again and blocks?
Circulating pump?

Sorry for the novel but I wanted to state everything I did and the boat did.

I need this boat for a wedding party on Saturday

Wonder how much sand you put into your exhaust? Might want to check.

Check the inlet to the oil cooler. Backflushing doesn't always get everything out.

You need to pull off every hose and start backflushing one section at a time.

Intake hose collapsing?

Bet the issue is in the p/s cooler, you will find impellor parts stuck there...Rob

Start backflushing and dont forget to get the sand out of the block too .:drink:

Joey...that sucks, as already stated, if you have a powersteering cooler or a mer. fuel cooler pull the hoses off at the coolers and back flush each section. Those coolers have restrictors in them to prevent debris from going through, they could be blocking or reducing water flow.

Similar occurance
 

I have transom mounted pickups. One trip out sucked up weeds/debris into sea strainer, causing clog, but did not let engine get over 160-170 as I caught the rising temp when it first happened, cleared the debris and continued on. It started running a little hotter 150 to 160 constant when I had a 120 degree thermo. Changed water pump (perfect condition, no missing vanes, but worn) back flushed all lines and coolers with compressed air and water. Nothing in them, rigged air/water connection to thermo housing and blocked off lines to manifolds, removed block plugs and installed lines with ball valves, would fill block with water, then pressurize with air from compressor up to 40 psi and then rapidly open ball valves, got tons of black gunk out of the block along with sand and grit. Repeated this at least 10 times each side (I'm OCD) and then buttoned up everything. Now that engine runs 120 to 130 constantly but now it is without a thermo as I never reinstalled it. Still think there is debris in engine somewhere that was not blasted out, but no matter as I have replacement engine sitting waiting for winter (cooler weather) to install. Old engine has about 670 hours on it.

My wife sucked up sand several years ago and I did all the same troubleshooting, but still had similar problems. What I found was the major problem was with the oil cooler. I pulled it and the power steering cooler out of the boat. Not much fun I might add!
There was some trash in the power steering cooler, but almost all of the cooling vains in the oil cooler were plugged completely with sand, like someone poored concrete in them. To clean out the oil cooler, I had to hold it up right, fill with water on the top, then tap it on a piece of 2x4 to loosen up the sand that would fall on the 2x4. It still took about 30 minutes doing this to get all of the sand out, as that crap was packed in so tight. Of course, I had to replace the whole sea water housing and impeller as it packed so much sand in it that it split the housing. Since then it stays at 130-140 all the time.
Rockie