Proflush engine descaler

[Washboy]

Hello - this is my first post so I hope it’s going in the right place .
I’m planning to flush my faithful old Volvo MD11C with Proflush engine descaler . I’ve read several threads about this and most people refer to setting up a recirculating system with pumps etc . I was planning to just remove the raw water intake from the gearbox housing and put a hose on it ( the way I normally winterise it) and stick the hose in a bucket of Proflush and then disconnect the exhaust outlet and let it blow into the same bucket so that it can circulate - I can’t see the need for a separate pump or am I missing something ?

 

[neil_s]

That's the way I do it on my Bukh. The trick is to get all the water and flushing agent to go back in the bucket after it comes out the exhaust. I have a piece of pipe that fits into the exhaust outlet to direct the exhaust into the bucket and drape an old towel over the top. This catches the water but allows the exhaust gas to escape. You will also need a deep bucket and some spare descaler to top up with. I do this with the boat afloat - the bucket thus has it's bottom below sea level and contributes some cooling. I find I can run the engine at fast idle like this for nearly an hour which seems to completely descale the waterways. I use Fernox DS3. Don't remove the thermostat but warm the engine up before you start.

 

[morgandlm]

If you disconnect the cooling water outlet from the injection bend to recover your recirculating fluid you risk "cooking" your exhaust hose when you then run the engine. What I think Neil_S is doing is collecting the water that comes out of the back of his boat so he has avoided this problem. On a positive note I have used Proflush successfully but used an old central heating pump to circulate the fluid for an hour or so having removed the thermostat.
David Morgan

 

[Washboy]

Thank you both for your advice - just to clarify, I was planning to remove the flexible exhaust pipe from the the elbow on the end of the manifold and catch the water in a bucket at that point - presumably this won’t cause the exhaust hose to "cook " ?

 

[Dellquay13]

Thank you both for your advice - just to clarify, I was planning to remove the flexible exhaust pipe from the the elbow on the end of the manifold and catch the water in a bucket at that point - presumably this won’t cause the exhaust hose to "cook " ?

If you mean to take the flexible exhaust hose off the tail end of the mixing elbow to catch the exiting water while running the engine, won’t you will have some very hot exhaust gases building up in the boat?

I have never witnessed anyone flushing their cooling system with the engine running, just the external pumped recirculation method

 

[Plum]

Hello - this is my first post so I hope it’s going in the right place .
I’m planning to flush my faithful old Volvo MD11C with Proflush engine descaler . I’ve read several threads about this and most people refer to setting up a recirculating system with pumps etc . I was planning to just remove the raw water intake from the gearbox housing and put a hose on it ( the way I normally winterise it) and stick the hose in a bucket of Proflush and then disconnect the exhaust outlet and let it blow into the same bucket so that it can circulate - I can’t see the need for a separate pump or am I missing something ?

Dealing with the exhaust gasses is the big problem if running the engine. I flushed mine (using Rydelime) for 2 hours and certainly did not want the engine running all that time. I used one of these little pumps Whale Orca Electric Bilge Pump 12v 500 BE0500

Www.solocoastalsailing.co.uk

 

[Washboy]

Thanks Dellquay 13 - I think that answers my question . Ventilation won’t be a problem but maybe the force of exhaust gas will be too much to keep the fluid in the bucket for circulation which would explain all the previous posts about pumps etc . I’ll give it a try without any descaler in and see what happens !

 

[Washboy]

Thanks Plum - just seen your response also . Seems like this is the tried and tested method so probably the safest route !

 

[VicS]

Thanks Plum - just seen your response also . Seems like this is the tried and tested method so probably the safest route !

Running the engine will warm the whole lot up and speed up the descaling process, taking care not to overheat things of course, but if you don't get up to normal running temperature the thermostat will remain closed and you won't get any circulation around the engine itself. For that reason you will have to remove the thermostat if you are doing it cold.g

 

[Dellquay13]

Here is a useful recent thread and blog about descaling

2GM20 raw water engine flush

 

[Washboy]

Thanks for the latest info and link - I’m hoping to give it try later this week .