Completed a Coolant system flush as I had to replace rusting bypass pipe. (below the intake runners on L-Jet injection)
Old pipe (44 years old):
New pipe (not stainless but coated with Por-15 and high heat paint):
No way to get a good picture of it installed but I also took the opportunity to replace old hoses and new BMW clamps.
The bleeding method I used works really well for me.
There are apparently several ways to purge the cooling system of air. With no particular favorite, Here is another, courtesy of E28 board and J.Rowe at Metric Mechanic:
"There is a sure way to bleed the cooling system on 'big' six engines.
1. After repair is made (before adding coolant) remove bleeder screw and run a small piece of wire down the hole to dislodge any mineral deposits..
2. Replace the screw, but leave valve 'open'.
3. Open heater control valve and add coolant until it begins to escape from the bleeder hole.
4. Now close bleeder screw and replace the expansion tank cap and tighten.
5. Remove the small coolant line that runs from the radiator to the
expansion tank AT THE EXPANSION tank and hold it as high as you can.
6. Now attach another hose the expansion tank in place of the one you've
just removed. BLOW (gently!!) through this hose until coolant emerges from the small elevated radiator hose.
7. Now remove the 'blow' hose and reconnect the small radiator hose to the expansion tank..
8. Now top off the expansion tank to the full mark.
9. Start and warm up engine and check for leaks!!"
Test drove the car, temp gauge stayed below middle and no leaks. Ready for the summer.
Old pipe (44 years old):
New pipe (not stainless but coated with Por-15 and high heat paint):
No way to get a good picture of it installed but I also took the opportunity to replace old hoses and new BMW clamps.
The bleeding method I used works really well for me.
There are apparently several ways to purge the cooling system of air. With no particular favorite, Here is another, courtesy of E28 board and J.Rowe at Metric Mechanic:
"There is a sure way to bleed the cooling system on 'big' six engines.
1. After repair is made (before adding coolant) remove bleeder screw and run a small piece of wire down the hole to dislodge any mineral deposits..
2. Replace the screw, but leave valve 'open'.
3. Open heater control valve and add coolant until it begins to escape from the bleeder hole.
4. Now close bleeder screw and replace the expansion tank cap and tighten.
5. Remove the small coolant line that runs from the radiator to the
expansion tank AT THE EXPANSION tank and hold it as high as you can.
6. Now attach another hose the expansion tank in place of the one you've
just removed. BLOW (gently!!) through this hose until coolant emerges from the small elevated radiator hose.
7. Now remove the 'blow' hose and reconnect the small radiator hose to the expansion tank..
8. Now top off the expansion tank to the full mark.
9. Start and warm up engine and check for leaks!!"
Test drove the car, temp gauge stayed below middle and no leaks. Ready for the summer.
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