D2 75 raw water circuit riddle

[elias]

Hi to all,
While wintering our BV44 we use the “ears” on the saildrive with hose on the saildrive while plugging a wooden cone on the lower inlet to force fresh water up to the system , then start the engine and wash the system while working the engine for health reasons .
On a Bavaria 50 tried the same setup and almost none water came out . I changed impeller , found that 3 blades where cutter in half . Changed the impeller, no luck , little water out . Tried with high revs the same . Raw filter clean , could that pieces created so much problem in the tubes ? I undo the raw water hose from pump to the heat exchanger couldn’t find any pieces .
Anyone with similar case?

[SYJetzt]

Normally you would have to find the missing parts of the impeller at the entrance to the heat exchanger. Remove the lid and take a look there. Check whether the heat exchanger pipes are free. See image.

[elias]

Thanks , I just had a look inside from the hose , I didn’t move to undo the cap , do I need new seals after the inspection ?

[SYJetzt]

To be on the safe side I would install a new gasket

[elias]

Sorry , I mean the fabric green one , I have easy and relatively cheap resource for the o rings .

[elias]

Just for similar issues , previous owner had install the inlet to the outlet so the pump was sucking from the higher pipe inside the mesh making difficult to start priming. I attach similar pic, pump side on 11