Rust in cooling system

[dorikin]

Took apart my thermostat housing, thermostat and rear connecting pipe behind the block and found a lot of rust inside. I also took a peak inside the water pump while the pipe was off and could see a lot of rust/corrosion build up on and around the impellers.

Is this a sign of previous owner using the wrong type of coolant or maybe just used tap water?

Is there any special chemical or additive I can use to get rid of all the rust in the block?

(PS. Engine is currently out on a stand)

[EKVTIR-T]

It can be from air being in the system

[SHOGUNOVDDRK]

^ Mmhmm

It's likely had water in the system, how was your radiator?

[bennjamin]

Drain , fill with distilled water and burp the air.
Go for a drive , come back drop fluid again and fill with proper Honda type 2 coolant or similar.
That should remove a fair whack of rust / sediment and prevent any further.

You can get products from parts shops that do a similar thing

[dorikin]

From memory the radiator was also very corroded inside the end tanks

So distilled water has some sort of properties that will help in removing rust from the alloy block?

The engine is on a stand atm, would it still help if I pumped some distilled water through the block

[eg5civic]

i dont think it would hurt, or even if you pumped weater through it forst then do as ben has said and fill it with distilled water and go for a drive.

[dorikin]

I just had a thought might some dumb but has anyone removed the timing belt and hooked up a power drill (or similar) to manually get the water pump going?

[mocchi]

fuark gotta replace water pump for sure now.
in4dorikinbuildthread

[bennjamin]

I just had a thought might some dumb but has anyone removed the timing belt and hooked up a power drill (or similar) to manually get the water pump going?

Don't do that.
Just replace water pump with a new part.

[dorikin]

Sorry probably didn't clarify

Only reason I wanna do that is because the engine is on the stand and I wanna get the water circulating to clean out the block

[Chr1s]

An engine sitting around for a while will do this eventually too, usually the surface and nothing too major like cast iron blocks due to the Aluminium. You can find chemical cleaners, CRC I think is one of them, or you can take it to your local machine shop and they can dip the block to remove as much of this as possible.

[cbauto]

dip sounds gud. nothing like a good dip