Coolant Colour??

[GuvGTI]

Need to find out some info for a few friends.
Car runs fine no problems, has had full service last year and recently but question on the coolant.

What colour should the coolant look like on a mk3 golf and for that matter all the mk's??

If it is a murky brown orange coffee colour what does that signify?

How often should coolant be changed?

Many Thanks

[Agreeable Slick]

Really, coolant colour doesn't matter a jot, it is coloured primarily so you can see leaks in pipes and on the radiator quick and easily should they spring one.

Orangey colour could just be because it has discoloured overtime, and needs changing, it could also be running sludge around your system.

Ideally it should be changed once a year on older cars, just to keep it fresh imo. Although most coolants now are guarenteed to last 3-5 years.

[GuvGTI]

cheers for the quick reply slick.

my mate was just a bit worried as he changed the coolant one year ago as it was this murky orange  colour then and the garage questioned to why this was.

Now had another service and same brown colour.
They said could be rust in the engine? hence they asked me as they was a bit worried for advice.

Whats your thoughts?

cheers

[Agreeable Slick]

I would be surprised if it was your engine, as the pathways are pretty robust, if it is a orangey sludge or suspended substance, then i would have thought it was the internals of the radiator rusting away, it might be an idea to just check to see if you can find out when it was replaced and consider a new one.
 
Other than that, just get some rad flush from halfords and give the entire system a good flushing out. Refill it and see how you go.

[GuvGTI]

was told rad flush has very strong chemicals and this could cause other problems at a later date? i advised against this but has been a possibilitym to them.

Thanks for the advice il see if the rad has been replaced, my suspects are that it hasnt.

[rubjonny]

I wouldn't bother with rad flush, it might do more harm than good!  When I do a coolant system service I just disconnect all the rubber hoses I can and stuff a hosepipe into every coolant hole I can find, and run it thru at a medium pressure till the water comes thru clear.

However if you don't remove the thermostat the block will still be full of old coolant so you wont be able to flush it through properly.  If you don't know when it was last done I'd replace it and flush the block at the same time

[GuvGTI]

thanks rubjonny,  so once a complete flush has been done including the thermostat it all should be ok.

so is the colour a worry then?

thanks

[rubjonny]

nah, prob just a bit of rust from the waterways, left over from before the last change.  If you don't flush all the old stuff out completly it will come back

[GuvGTI]

nice one