Flushing and analyzing cooling system of Volvo Penta 2003 without turbo while in garage.

[@JohnDeMarsh]

You need the correct exhaust riser. (I have this engine) you can get a VP riser or an aftermarket Stainless one, both have some connections. The pipe coming out of the thermostat housing will go to this exhaust riser. The pipe coming out of the engine (near the air intake) will also go to this riser. If there is no water flowing out of your thermostat housing it is because the engine is not warm and the T-stat has not opened. You can remove the housing and T-Stat to test flow. However note that the gasket for this assembly is actually on the Thermostat itself, so it may leak a bit while you test that. The exhaust riser in this video is homemade (not bad necessarily) and does not have the connection points in the correct locations. Cooling water comes in from the sea, through the gear box, and THEN to the pump suction side.

[@SM40]

All of the questions you mentioned are in the manual which can be googled.

[@markkimba74]

Your thermostat isn't hot so will be closed so flow will only mainly come out of one of the outlets. You need to remove the thermostat when flushing or the flow won't go all around the engine block and cylinder head.

[@interestsandreparations9896]

That makes sense

[@matui6983]

You def have to move the water injection point to the position you pointed to on your exhaust riser. Where it is in the video is oh so wrong.

[@interestsandreparations9896]

Thank you for the comment. It seems the exhaust is made out of a stainless steal pipe farmers would use. I will need to change it.

[@matui6983]

The concept is fine. Material will be 316 s/s so that will work. Freshwater flushing is the best thing you can do for the exhaust and the engine. But with that riser, move the water injection pipe from where it is now to where you pointed. Much much better position. Will the rest of the pipe get hot? Yes but it looks like a big diameter pipe which will reduce backpressure. And you can always wrap the rest of the pipe before the water injection point with car header/extractor material. Will stop you getting burnt and will help in reducing engine room temperature.

[@PaulBaker64]

Those pipes go to the gearbox