3ym30 overheating

[clonlara]

Hi guys. My engine overheated recently due to a water pump belt breaking. When I checked the impellor it too had disintegrated. I don`t know which happened first.
I replaced both the belt and the impellor and removed the debris from the impellor from the outlet hose to the heat exchanger.
I noticed after motoring for about 40 minutes that I was getting a small amount of steam from the exhaust. I assume both things are connected
How do I ensure that all the debris is removed and how important is it that it is removed. could some have gotten up into the heat exchanger.
My exhaust outlet is under the hull of the boat on the waterline and so it is difficult to see how much water is being pumped out.
Any body got any ideas as to what to do next.
Thanks in advance
Colin

 

[VicS]

Check the inlet and strainer

Check the exhaust outlet elbow/water injection

Clean the heat exchanger of any debris that might be restricting the flow

 

[clonlara]

Thanks Vic As this is my first indirectly cooled engine do you have any advice as to how to go about cleaning the heat exchanger
Colin

 

[vyv_cox]

Thanks Vic As this is my first indirectly cooled engine do you have any advice as to how to go about cleaning the heat exchanger
Colin

You can download the workshop manual at Yanmar 3YM30 Manuals | ManualsLib

 

[peteK]

May be be easier if you look on utube for cleaning your heat exchanger.

 

[Deleted member 478]

This YouTube video might help

 

[Halo]

Don’t get too panicked. These engines often breath visible vapour which may not be steam. Run it until it’s “ steaming” and take the temperature of the water coming out- is it very hot ?
All previous advise is good and you will need to clean heat exchanger at some point.

 

[WindyWindyWindy]

Just took the pump to bits in my 3YM30 to find the old impeller parts had been stuffed up the inlet pipe, so check that too.

 

[david_bagshaw]

A wet vac is useful for getting the bits out. how much did the engine overheat, as i would keep a good eye on the coolant level in the header tank. . would be a good idea to dive the tube stack a remove and wash, and new o rings and the engine side a flush as well as the over heat will have put some previous settled muck into the circulation water..

Unusual for belt and impeller to fail at same time.. so fresh water pump might havegot v hot? so watch for leaks from its seal.