TAMD41A overheating

thanks for replies to check elbow do i just remove plugs on elbow and rev eng. in neutral to check flow and is there anyway to check raw waterpump it looks like it pumping plenty of water i replaced impeller in fall and if i got to check cooler i guess it has to come off eng. to clean
thank you,
goody

Pull raw water hose off the elbow and let it run into a bucket....it has to flow good volume

Hey, I have a very similar problem that goody had with overheating. new impeller, new thermostats took heat exchanger clean as a whistle good flow at elbow changed exaust elbow still overheating at 3000rpm aprox 200 deg going to try muriatic acid through system and heat gun to chase it what next?

wondering if your impeller went bad there might be a peice of impeller under the pulleys on front of engine there is pipe with a tee on it that happened to the owner before i got boat he removed the tee it now a peice of hose he couldn't figure out why the boat kept overheating they tried acid new pump cleaned exchanger but that is what it was

Sorry to inject this suggestion if you've checked it already. I had a similar problem with my Volvo strerndive. The raw water pickup connector was leaking air whenever the boat came up to plane at speed and the engine would overheat immediately. As soon as I slowed down and the pickup became submerged again, the engine would cool down.

Thanks for the tip . From what I hear it does'nt take much to restrict water flow. Even end cap on heat exchanger has to be in right possition or it will overheat. fri i try acid bath , heat gun and anti freeze sniffer to see if head gasket leaks. also trans heat exchanger and aftercooler if that doesnt work I call in a pro . Thanks for the advice much appreciated. let you know next week outcome.

Not too sure about acids such as muriatic acid... from my experience it degrades good metal as well to a black rust, but does not move the blockage, but tries to dissolve it. If it is something foreign like rubber it has no effect. One member in the past post suggested dishwasher soap with a abrasive grit... not the gently stuff. Run engine till hot , to loosen scales then flush the crap out. Let me know which way you go and if it works out.

I flush with SaltAway which is designed for the purpose. Different engines, but I have a sgarden hose that plugs into the anode hole at the front of my intercooler. I use the garden hose to run fresh water through the system and push the salt water out (leave running for an hour or so). I then remove the raw water pipe between the end of the heat exchanger and the turbo. Garden hose goes onto a small bilge pump in a bucket of SaltAway solution and the heat exchanger hose gets fed back into the bucket. Leave the bilge pump running for a few hours to circulate the fluid through the whole cooling system, then put it all back together with the SaltAway solution still in the system overnight. Next day just run the engine and you are back to normal. Takes about 30 minutes of actual work per engine once I set it up the first time, so I can do it quite regularly. Only thing it doesn't fully flush is the riser elbows so I pop them off every couple of years to check them. Interestingly I have stainless elbows with 'slots' rather than the normal 'holes' for spraying into the exhaust. At my last check at 3000hrs they looked like they had just come out of the factory.