Acid flush raw water system.....

[racclarkson@gmail.com]

Yes, that's what I did.

Then you’re likely losing solution cause the pipes look unchanged. Did you remove all the zincs? Did you remove the impeller? Did you close the seacock? All all the raw water exits returning to the bucket? Do you have dripless shaft seals? Did you have to add to the solution? If you can check off those items, you haven’t given the acid time to work.

[oscarvan]

Then you’re likely losing solution cause the pipes look unchanged. Did you remove all the zincs? Did you remove the impeller? Did you close the seacock? All all the raw water exits returning to the bucket? Do you have dripless shaft seals? Did you have to add to the solution? If you can check off those items, you haven’t given the acid time to work.

All zincs out.
Impeller out.
Seacock closed
Went IN through the exits before the T (one of them the other blocked) and OUT through a lid with hose fitting on the raw water pump.
Dripless shaft seal hose was pinched off with appropriate tool.
I got 5 gallons back out.
It was in for almost 2 hours.

Plenty of flow plenty black.

I can do it again in the other direction.

[racclarkson@gmail.com]

All zincs out.Impeller out.Seacock closedWent IN through the exits before the T (one of them the other blocked) and OUT through a lid with hose fitting on the raw water pump.Dripless shaft seal hose was pinched off with appropriate tool.I got 5 gallons back out.It was in for almost 2 hours.Plenty of flow plenty black.I can do it again in the other direction.

Then likely some broken off zincs in HE neutralized the solution. Do it again.

[racclarkson@gmail.com]

Then likely some broken off zincs in HE neutralized the solution. Do it again.

Meant to add that if above is the case, it would also indicate enough anode material to block some water flow. You should be able to get a view with your scope. Either way, your before and after pics indicate little action from the acid solution. So, you’re likely dirtier than we thought or have zinc in there. And it’s always a good policy to reverse the flow for 15-20 mins at the end to help any sediment to find its way out. To get the best acid cleaning results, loop the return hose well above the highest point of the raw water circuit to eliminate any voids. It’s a good idea to do the same with your rinse water. Finally, if the before and after pics of your HE are what they are, you can expect similar poor cleaning in your other choke points; ie, intercooler, fuel cooler and gear cooler.

[oscarvan]

To wit, the flushing was done counter flow, ie IN the exhaust end of it and OUT the raw water pump. Rinsing was done normal flow. As we speak we are running solution normal flow, ie IN the raw water pump and OUT the exhaust. Yesterday I in fact had the outflow hose routed above the highest point.

https://youtu.be/90rWZGyA7TM

[oscarvan]

Outflow hose routed above highest point of engine:

[oscarvan]

1 hour. No change in color of the solution. Just for craps and giggles loosened one of the plugs in the heat exchanger. There be fluid there.

[rustybucket]

Klean Strip Concrete and metal prep..........

Curious as to why not using the recommended blend of muratic that DD recommends in the manual?

[racclarkson@gmail.com]

1 hour. No change in color of the solution. Just for craps and giggles loosened one of the plugs in the heat exchanger. There be fluid there.

Turn off the pump, let the HE drain into bucket and then remove that plug that doused you and scope it.

[jim rosenthal]

A couple of years ago I took both HEs off my Cummins diesels and took them in to be cleaned. This involved draining both engines etc. If I understand right, the type of cleaning Oscar is doing just cleans the seawater side, right, not the antifreeze side? Is there a similar recommended procedure for Cummins diesels, anyone know?