Cooling system changed colour noticeably

[Ezookiel]

OK, you all know my cooling issues, or should by now.
I've had something really odd happen.
We drove the car on Christmas day a 400 Km trip with some quite solid hills in it, including climbing up out of Canberra where the temp has always gone up to 70% even in winter.
This trip, I never got the temp gauge over 55% and generally sat on 45% the whole way. That alone is unheard of for this car.

Got down to Bombala, and the wife's uncle wanted a look. He's rebuilt more diesel engines than I care to think about, has done all his tractors, trucks, etc. and is even a mad keen member of some steam engine club.

So we opened the radiator cap to show him where the new cap had been moved too etc.
And while doing this checking of my water levels, which were down about 0.5 of a litre, I noticed the water had gone really really really dirty brown looking.
It had been running coolant, has new radiator, new hoses, new pump, new everything, including two engine rebuilds.

So, why would the water now be soooo dirty and the cooling now running beautifully?

If I didn't know better, I'd wonder if it's blown out some kind of blockage deep in the cooling system that we hadn't gotten rid of and flushed dirty water into the system, but made the system suddenly run better.

Is this actually possible?

[bogged]

So, why would the water now be soooo dirty and the cooling now running beautifully?

Did you have the block flushed? if not, the block will have heaps of sludge, rust scale, and crap in it. the only way is to have the WHOLE system reverse flushed and you will never get it perfect, but heaps better..

YMMC

[physh]

If it's really dirty, yeah I don't see why it couldn't be from a blockage, or even from a clump of rust somewhere maybe?

But if you have new rad, hoses, pump, and an engine rebuild then I'm not sure... it might have been something else.

Has your heater been working better too?
Possible that there was a blockage in the heater component, or perhaps heater valve was partly gunked up or something like that?

Another option may be that there coulda been some crud in the galleries of the block itself?

Dunno, but who's complaining? Sounds like something let go and finally the problem may have been sorted:)
Flush it with more good stuff, hopefully that's the end of your heat problem!

[Ezookiel]

Oh God I hope so.

But still have a list of jobs I want to get done as money allows just to make sure.
Viscous Coupling,
Turbo Service,
Fuel system service.
And an auto trans service, cause she's behaving like a dog in that area lately.

[Gribble]

Sounds like it wasnt flushed properly.

[Ezookiel]

Was originally reverse flushed, then soaked overnight with a bottle of one of those cooling system flush/soak products.

Then followed a year of other problems, but the coolant becoming dirty rusty coloured wasn't one of them.

But why shouldn't this car keep doing weird things to me? It's done nothing but weird things to me since day one.

I await the next installment of oddities.

[75 cruser]

if its been mucking up from day one sounds like to move the problems on to a new owner

[chunderlicious]

engine rebuilds normally involve a full engine and head acid soak and good clean to make sure the galleries are all clear and rust free and shit

[Ezookiel]

Yeah, sorry a rebuild is probably exaggerating a bit.
It got so hot once it grabbed a couple of pistons.
So it got new head (brand new apparently) gasket, pistons, etc etc
Not really a full rebuild.
It actually had the head done twice, because inexplicably just after it went back in for the 1000km tighten up of everything, it blew the gasket again in a big way, and had to be done a second time (felt sorry for the company that did it, they did it all under warranty, but must have lost them money)

The reverse flush was supposedly done by a mechanic who was a work colleague, but since so many of the other jobs he supposedly did have since been found to be either not done or dodgy, wouldn't be at all surprised if he didn't do, or didn't do properly, that first flush.

THe soak was done by me a few months back before trying to limp the blown gasket along with chemiweld, which meant giving the whole system a good clean out. I used some cleaner from Autobahn/SC/etc that you leave in overnight to have a good munch on anything it can eat, then flushing it all out.

[Dane]

I bought a car once that had had the engine rebuilt but the heater didn't work at all. It never worried me much in North Queensland but after I moved to shitoria I decided to sort it out. The heater hoses were solid blocked full of crap and the bloke had spent 3 grand plus on the engine rebuild after overheating it and just had the engine refitted without properly cleaning out the cooling system. It is entirely possible that your cooling system had a big blockage in it somewhere (engine or heater)that has been dislodged. Sounds good if it is true, give it a good flush and new coolant and see how it goes. Would be nice if it solves your problems....