Brown sludge

[jed1y0da]

Hi, I've got brown sludge in the header tank and evidence of it when i take the rad cap off. There's no sticky mayonnaise in the oil either.

I've had been losing water for the last few months (about 1/2 litre a week) which i've been topping up with coolant/water. I eventually tracked this down to a leaking core plug.

When i rectified the coolant leak I had it checked by Fred at discount trucks (sniffer test/pressure test etc) - all fine.

Now it's started losing coolant (about 1/2 litre for every 40 miles) of driving but there's zero evidence of where it goes. I've even put the UV dye in to try and see where it might be leaking from, but it's bone dry underneath. I've had it checked again (sniffer/pressure test) - all good.

So i have two probs:

1. oil entering the cooling system - could it be the oil cooler or head gasket or something else?
2. magically vanishing water

As a side note I've driven the van from the isle of wight all the way up to Edinburgh and back last month without any probs (still had brown goop and losing water).

PS van is 96 2.5TD - had it for 8 years

[Northern Bongolow]

the way i view it is, you had a leak, the core plug, this would have let air in, or at least allowed the motor to run at a lower coolant pressure, this would allow the coolant to boil earlier maybe just locally to the leak, or boil the full system. then the leak was fixed but the gasket/head was weakened, so now the leak is fixed the system will hold a higher coolant pressure, this may now be enough to leak from a crack in the head or cross the gasket.
brown sludge is usually a sign that the engine or system has been cooked, the high temps free off the rust scales inside the system making a soup. this may have been done whilst running round topping up coolant for a period of time or by poor system bleeding between repairs.
was the core plug rusted out from behind, they usually go that way, this again points to non regular coolant changing in the past. which core plug was it,

[teenmal]

the way i view it is, you had a leak, the core plug, this would have let air in, or at least allowed the motor to run at a lower coolant pressure, this would allow the coolant to boil earlier maybe just locally to the leak, or boil the full system. then the leak was fixed but the gasket/head was weakened, so now the leak is fixed the system will hold a higher coolant pressure, this may now be enough to leak from a crack in the head or cross the gasket.
brown sludge is usually a sign that the engine or system has been cooked, the high temps free off the rust scales inside the system making a soup. this may have been done whilst running round topping up coolant for a period of time or by poor system bleeding between repairs.
was the core plug rusted out from behind, they usually go that way, this again points to non regular coolant changing in the past. which core plug was it,

This guy certainly knows his Onions.

[cmm303]

Secretly French maybe?

[Bob]

I've never known Ady surrender.

[Northern Bongolow]

i was thinking about it, but ive been up since 4 this mornin

[jed1y0da]

Hi, it was the 2nd core plug from the left and yes it rusted from the inside out.

I'll flush the whole system this weekend - see what goop comes out!

[jed1y0da]

slightly related - how easy is it to remove the header tank? I was going to clean it with some ball bearings and mild acid solution if i can get it off as it looks like the inside of grannys teapot

[jed1y0da]

found this - seems straight forward:

http://www.westonwarrior.talktalk.net/m ... 0tank.html

[Bongolia]

Hi, I've got brown sludge in the header tank and evidence of it when i take the rad cap off. There's no sticky mayonnaise in the oil either.

I've had been losing water for the last few months (about 1/2 litre a week) which i've been topping up with coolant/water. I eventually tracked this down to a leaking core plug.

When i rectified the coolant leak I had it checked by Fred at discount trucks (sniffer test/pressure test etc) - all fine.

Now it's started losing coolant (about 1/2 litre for every 40 miles) of driving but there's zero evidence of where it goes. I've even put the UV dye in to try and see where it might be leaking from, but it's bone dry underneath. I've had it checked again (sniffer/pressure test) - all good.

So i have two probs:

1. oil entering the cooling system - could it be the oil cooler or head gasket or something else?
2. magically vanishing water

As a side note I've driven the van from the isle of wight all the way up to Edinburgh and back last month without any probs (still had brown goop and losing water).

PS van is 96 2.5TD - had it for 8 years

Any trace of the UV dye at the tailpipe or rad matrix?
Is the sludge oily or muddy?
Has it had a compression test or a leak down check?
Which core plug was it 2nd from left?
Any running faults/driveability issues?
Sweet smells when running the heaters?
Flushing at this point would not help the coolant loss issue and may well make it worse.

[wonkanoby]

bottom from under water pump can be a hard one to spot

[Gasy]

Brown sludge
Thought I was at work for a mo
The exact same process happens in radiators
I've often thought of putting some radiator sludge removal chemical in the cooling system before you drain and flush it throughout
To break up the sludge
I'd recomend a brand name if any one wants to try

[the1andonly]

Brown sludge
Thought I was at work for a mo
The exact same process happens in radiators
I've often thought of putting some radiator sludge removal chemical in the cooling system before you drain and flush it throughout
To break up the sludge
I'd recomend a brand name if any one wants to try

I would be wary of using a chemical cocktail intended for a Cu Fe system in an Aluminium Iron system. Anybody actually done it or any real Chemists out there.

PS are car radiators still made of copper. Alumium and Plastic?

[Gasy]

Sure it won't do any harm
Boilers are made of
Aluminium
Iron
Copper
Rubber
Silicon
Plastic
Stainless
And these sludge removers are suitable for all

[the1andonly]

Good to hear it.
On other forums especially Biofuels and the manufacture of FAME I've seen some pretty cavalier atitudes to Methanol compatability and Health and safety.
But not from a gas man eh