Overheating Issue:

[scullersrun]

2004 21I w/ 335hp vortex eng. Once the boat is at operating temperature (175 degrees) and I pull a skier /boarder a mile or two, the temperature will rise close to 200 degrees and would continue if I don’t tell the skier to release. When I slow down to retrieve the skier, the temp returns to std operating temp. Of course once I increase the speed the temp rises. This just started to happen. I've changed the impeller and thermostat. Anyone have any ideas?

[bobbysky]

pieces of the old impeller stuck in the lines causing a water shortage.

[whitlock87]

Flush the engine. Make sure to open all the petcocks to ensure you have good flow at locations.
Also flush back from the engine through the trany and out the lake pickup, to make sure there are no clogs. One last thing, my marine power 5.7 330 hp runs at 140

[scullersrun]

Overheating Issues

Note: When I changed the impeller the old one was in perfect condition.
To flush the engine, I open all the petcocks and flow ports (as if I was winterizing the boat) to ensure I have good flow. Do I use a hose at the various ports or lower the boat into the water, start the engine and let that flush the system? Or, is there another method?
Which ports flush back from the engine through the trany and out the lake pickup?

[kko]

check the trans cooler for a clog.

[chpthril]

Note: When I changed the impeller the old one was in perfect condition.
To flush the engine, I open all the petcocks and flow ports (as if I was winterizing the boat) to ensure I have good flow. Do I use a hose at the various ports or lower the boat into the water, start the engine and let that flush the system? Or, is there another method?
Which ports flush back from the engine through the trany and out the lake pickup?

Pull the inlet hose off the impeller housing and shove a garden hose down it, turn it on and see what tries to come out the scoop.

When running on a fake-a-lake, what kinda water flow do you get out of the exhaust and are both sides fairly equal?

[scullersrun]

Overheating issues

I have never run a fake-the-lake, do I insert a garden hose into the hose on the opposite of the inpeller intake? Someone else mentioned the trans cooler clogged, any idea how to verify?

[chpthril]

You dont actually need a fake-a-lake, just pull the hose off the scoop and shove in the garden hose.

To clean/back flush the trans cooler, pull the inlet hose off the raw water impeller housing and run the hose down it and see what comes out. Now, dont run the engine at this point, this is just to clear the raw water intake plumbing.

[scullersrun]

Overheating issue

I corrected the problem. I pulled the impeller inlet hose and flushed the lake intake. Took the boat for a ride and after 5-10 min of running at 2800rpm the temp gage started to increase. I opened the cover and noticed the hose leading from the impeller to a metal canister was solid. The hose coming out the canister was soft, I could pinch it, yet water was flowing. I returned to my dock and removed the outlet hose from the canister, which turned out the canister is a baffle. There I picked a couple of small pcs of impeller, so I removed the inlet hose. I could not believe the amount of impeller pieces, enough to make an impeller. I purchased the boat used in 2004 (53 hrs) and since then I replaced a broken impeller once with only one blade partially broken. Therefore, this material has been blocking the inlet baffle all these years. After a clean out the boat operates at 150 instead of 175 and at 4000rpm the temp gage remains stationary.
Thanks for your help everyone.