Author Topic: Goo in heater core, dark coloured coolant. (Read 3163 times)

sepehr · « **on:** December 14, 2006, 08:10:40 PM »

I took out my heater core (royal PITA).

Draining the coolant, i noticed it was pretty dark in colour (is this normal?). Previous owner used regular prestone antifreeze, so it was green.

Flushing water through the heater core, I noticed that some small black gel like pieces came out.

Does anyone know why this would happen? Are the rest of the coolant passages/radiator gonna look like this? Is this related to the profile gasket?

thx in advance

ak96ss · « **Reply #1 on:** December 15, 2006, 04:19:03 AM »

BMW antifreeze, which is really the ONLY thing you should be using, is dark blue.

The PO may not have completely flushed the system when he started using the green stuff, so it would mix and darken the green stuff.

I wouldn't put green (or orange) stuff in, there is too much anecdotal evidence that it causes as much harm as good. More than likely the rest of the cooling system does look like that - I would seriously consider a good flush.

Probably not related to the profile gasket - that would mix oil with the coolant, you'd end up with a milky solution.

sepehr · « **Reply #2 on:** December 15, 2006, 04:12:42 PM »

good to hear thanks guys

m42 fan · « **Reply #3 on:** December 19, 2006, 01:16:44 PM »

yeah, don't cheap out on your antifreeze. $20 for a gallon every other year looks like a good deal when you compare it to the nightmare of trying to get your old w/p out of the block when it's frozen in place...

Brian

Alpine003 · « **Reply #4 on:** December 20, 2006, 10:04:49 AM »

I've known several people that have used the green coolant for several years on older BMW's without any issues. Most of the newer coolant these days have a slightly different composition than they did awhile ago to meet the demands of the newer cars. However, the e46 models on up seem to be more sensitive to coolant issues for some reason and I definitely use the BMW blue stuff for that car.

I'm hoping I do find particles coming out of my heater core when I flush it so I don't have to replace it. I believe it is currently clogged right now.

kowalski · « **Reply #5 on:** December 22, 2006, 04:16:06 AM »

it just has to be coolant with no sulpher or other minerals (there was 3 things, but i forget what the other 2 were). Also make sure its mixed with distilled water. thats all the bmw stuff is, and as long as you make sure your anti freeze is clean, and you add distilled water you will be fine.

Alpine003 · « **Reply #6 on:** December 22, 2006, 09:34:49 AM »

Quote from: kowalski;16043

it just has to be coolant with no sulpher or other minerals (there was 3 things, but i forget what the other 2 were). Also make sure its mixed with distilled water. thats all the bmw stuff is, and as long as you make sure your anti freeze is clean, and you add distilled water you will be fine.

I think the Phospate level is another item out of the 3 to look for. I guess you can always use blue dye in the coolant if it will make you feel better.

RED IS 91 · « **Reply #7 on:** December 22, 2006, 10:26:15 AM »

I put Zerex Phosphate Free with Distilled Water (bought at Walmart).
Zerex is recommended for Mercedes so I figure it's good enough for me.
I believe all your looking for is Phosphate Free with Distilled Water.
No minerals to frig up the Aluminumn parts.