View Single Post
  #5  
Old 11-21-2020, 11:38 AM
crystalworks's Avatar
crystalworks crystalworks is offline
Premier Member
 
Join Date: Jun 2014
Location: SA, TX
Posts: 5,040
crystalworks is on a distinguished road
Quote:
Originally Posted by andrewwynn View Post
The difficulty is in that until detergent is used the oil will find high spots anywhere in the block and cling to things when drained. I don't think it's harmful to have a little oil so were it me I would do as described above.
Exactly. Last flush I did on a very dirty (rusty and oily) system I ran a few coolant system cleaners through with cheap coolant all the way up to temp. And then ran gallons (hose constantly on in expansion tank) while the radiator drain was open. Ran it for 30+ minutes until water coming out was same as water going in. Then shut off and drained the system and filled with distilled water. Then drained that and filled with bmw blue at 60/40 to compensate for some of the water still in the passages/block. Worked great, never had another issue with the cooling system on that car while we owned it.

It took a lot of time (whole process was at least 2 hours), but was probably pretty effective.
__________________
2005 X5 4.4i Build 04/05 Maintenance/Build Log
Nav, Pano, Sport (Purchased 06/14 w/ 109,000 miles) (Sold 8/15 w/121,000 miles)


2006 X5 4.8is Build 11/05 Maintenance/Build Log
Nav, DSP, Pano, Running Boards, OEM Tow Hitch, Cold Weather Pckg (Purchased 08/15 w/ 90,500 miles)

2010 X5 35d Build 02/10
Nav, HiFi, 6 DVD, Sports Pckg, Cold Weather Pckg, HUD, CAS, Running Boards, Leather Dash, PDC, Pano (Purchased 03/17 w/ 136,120 miles)
Reply With Quote

Sponsored Links