How to clean inside of water cooling cases

[Fishingfool21]

We recently pulled apart my 1989 pro 50 and are in the process of rebuilding it, I was wondering how to clean the inside of the whole water cooling system (the white buildup) is there a certain chemical y'all recommend or process on how to do this. Thanks

[robert graham]

There's a product called Salt Away that can be circulated through an assembled outboard motor to clean all the passages....Some folks have used it with success but I also believe there are plenty of outboard owners/operators(fresh and saltwater) who just don't worry a lot about deposits....Of course it's always a good idea to flush a motor with fresh water after each use, but I'll admit I don't always do it....so far, so good!...

[TownsendsFJR1300]

Some interesting and likely helpful reading;

http://www.yamahaoutboardparts.com/f...g-th19434.html

[99yam40]

I am not sure how to do it with motor all torn apart.
Just soaking in a bucket might do it ,but you will have the solution on parts that may not like it, not just the cooling passages

[TownsendsFJR1300]

Thought the same thing.

I think brushing it on and into the coolant passges you can access, with a paint brush would work.

Then, maybe rinse with fresh water from a small, squeezable plastic container (to keep the water in a specific area, not on machined surfaces). At least get the heavy stuff out you can see...

Most of the salt build up (that causes issues) is usually in the head and block around cylinder walls, easily accessable with the head off..

[amahaork]

soaking, brushing, etc. - I tried everything. nothing works. finally gave up and scrub it away with piece of wood.

[BQUICK]

What I've found is once you have salt buildup you have to get in there and get it out. Flushing just wets the deposits down and corrosion eats away.

I tore down a 50 Merc (Florida motor) that had been flushed with freshwater 6 months earlier and inside it still had wet salt deposits. Ate a hole in the block.

Saltaway and such is really more for prevention than removal.

[BayBum38ft]

I have been researching this product, it may be what you need.

RYDLYME Marine: The Ultimate Biodegradable Marine Descaler! | RydLyme Marine

[TownsendsFJR1300]

I have been researching this product, it may be what you need.

RYDLYME Marine: The Ultimate Biodegradable Marine Descaler! | RydLyme Marine

In post #3, the link speaks directly about Rydlyme how it worked along with pictures..