Engine and Cooling System Flush

#1

What is a good cooling system flush product? I’ve got a 89 325i, and the coolant was brown and nasty, I flushed with water already, but it’s now brown again. Went to Walmart and found Prestone flush and some other prestone cooling system flush product, just trying to figure out the best for a my bmw.

I changed the oil for the first time last week. It was pretty nasty. Any one have any thoughts on flushing out the engine internals with an engine oil flush product? What brand is good if this is a good thing?

#2

never tried an oil flush additive type thing, so I can’t help you there. But I used the prestone coolant flush stuff with good results before, I don’t see any problem with that stuff.

#3

Use any of the major brand coolant flush products. And I always fill mine back with distilled water and Water Wetter during the summer months.

Regarding an oil system flush…I would not use one on an E30 engine. Our engines like to ooze a little oil anyway and flushing out the crud that may be plugging small leak holes might be somethiing you don’t want. I used one on a older Toyota engine and it developed an oil leak within one day.

I would fill it with a light oil (5W30), install a new filter, and run it for about 20 minutes. Drain this, replace the filter, and fill with the proper weight oil.

Carter

#4

I agree with Carter. Just change the Oil more frequently for awhile with the cheapest stuff you can find. Then switch to a good detergent oil. I’ve been using Maxlife in my car for instance. Same for the cooling system…Distilled water is cheap.

I’d run some STP in the gas. I think If I had an M20 engine I’d be more scared of carbon deposits in the intake and combustion chamber.

#5

Most opinions are DONT USE OIL FLUSH, just run a few fresh oil changes through the system from one of the othe bmw forums. Thanks