Brown slime on my radiator cap

[Killr6]

as the tittle says, brown slime is on my radiator cap, now ive done my research. i have no leaks im not losing coolant, and my car runs fine, my coolant is still bright green. and about 500kms ago i had my radiator flushed.

1. im not convinced its a blown head gasket, as there is no milky stuff in my oil/oil cap, and the stuff doesn't look or smell like oil its like jelly

2. i have an old water pump could be rusty?

3. Tranny fluid?

4. Inlet manifold gasket?


on Monday i will be getting a new water pump and a transmission service, so if anyone has had this problem please give me some idea's.

[Killr6]

pics ! as you can see its not bad, but yeah.

[pablo]

Join the club, had the same problem for over 5 years. I have put it down to inlet manifold gasket nackered. Try tightening the inlet manifold bolts, I found several quite loose, though, after tightening,the oil still appears on cap.

[Richard Moss]

Mine does the same - no noticeable coolant loss, no oil in coolant, no "mayonnaise" on the oil cap or radiator cap. I just wipe it up every few thousand KM and carry on driving the car.

[TI3VOM]

There is nothing wrong! All it is is the pellets they put in when they flush your system out!!

[Killr6]

There is nothing wrong! All it is is the pellets they put in when they flush your system out!!

cheers for the replys guys il tighten up my inlet manifold gasket to be safe.

and i thought only holden used these? i went to a radiator shop.

[CAPRILICIOUS WL]

Dads v6 Vy series II has the same problem and I know that it doesn't have the pellets in there.

So could it be the absence of the pellets maybe?
Or
I rekon it may be the wrong type of coolant in there???

Just a thought...

[edals]

Its The Holden Pellets, Leaking Trans Cooler or leaking inlet manifold gaskets. Flush The Whole System and see how you go.

[Killr6]

alright well il do a full flush when i chuck in the new water pump. il check my inlet gasket.

cheers boys.

[rockie]

dont panic it happens to all commordores just clean it every now and then as long as its not milky its ok

[Full Spectrum]

Just had mine replaced not long ago. One of the most common problems with the V6. Had mine replaced with a Mace engineering one .

[TI3VOM]

My old radiator had the build up of brown sludge in it, when I got it replaced more than two years ago the brown sludge is nowhere to be seen.
I have just last week gone a purchased some of the pellets for the radiator to put in there myself and this is what they look like:





The bloke at Holden said they lubricate the water pump and they will leave a brown sludge like residue in the overflow bottle and under the radiator cap.

[Killr6]

pics dont work mate. anyone know how hard expensive it is to get a new inlet manifold gasket?

[TI3VOM]

The pics work on my computer and they have been uploaded the same way I always upload pics onto this website.
Not sure why there not working, maybe check again?

Either way before you start changing parts, check with the place you took your car to and see if they add the pellets to your radiator.

[Killr6]

yeah they are working my bad.

yeah i will it was a radiator shop so he might have used them.

[BarossaVT]

I reckon you should replace the Auto trans cooler seals in the radiator before your problem gets any worse. They have a habit of leaking over time..even years & allow your coolant & trans fluid to mix. Starts off as a bit of brown sludgey build up around the cap but when they really let go it turns into a samon paste and will go right through the radiator & water jackets clogging everything up. Not to mention the leaking back into the trans itself & causing a major rebuild if its gets that bad. Prevention is better than cure!!!

[pablo]

The sludge I have under the cap AND in the overflow bottle is dark engine oil, no mistake about that, as I haven't used those pellets for several system flushes. Also, the recovery bottle ceased to work about the same time I noticed the slight build up of oily sludge under the cap.
I just wipe it off every now and then, and keep an eye on coolant level in radiator incase of any sudden drops. Been doing that for about 6years now.

[Killr6]

meh im going to be on the safe side and get my mechanic to have a good look over, all the issues discussed and go from there.

[BarossaVT]

Good idea but do replace the trans cooler oil seals in the radiator or better still disconnect the lines all together & run an external trans cooler instead & save yourself a lot of mess & expense down the track or even just around the corner!

[webbiegareth]

Mine was exactly the same as those pics.... I had my inlet manifold gasket replaced and it's been much better since then It cost a few hundred to get done, probably a bit more than that if I recall as I also got the rocker cover gaskets done at the same time (mine were leaking out oil everywhere).