Procedure for radiator flush?

[madkow70]

Hello:

Does anyone have the proper procedure for radiator coolant flush? Is it just as simple as draining the radiator and refilling it with fresh coolant? Or should I need to follow more steps to flush out the rest of coolant?

Also, how do I check the oil level in my diff?

Thank you everyone for your help in advance.

D.J.
.

[TMB_540i]

A radiator flush is different then just draining the old fluid and putting in new coolant. You may want to check out Bavarian Autosports web site, I think they covered some of the maintenance topics in their last newsletter.

As for checking the differential fluid, you should have an upper fill plug and lower drain plug on the differential body. You will probably need a 14 or 17 mm hex socket to remove the fill plug. Just remove the fill plug and the fluid should be right at the top of the fill plug lip. On mine, it always gushes out a bit.

Hope this helps.

[madkow70]

the BavAuto's newsletter just mentioned the coolant changing interval and the fact that it should be changed, etc... It did not go into step by step instruction on how to (flush out the rest of the coolants).

So the differential fluid-wise, there isn't a way to check the level then? Obviously, the only way is to just top it off? Do you use a manul pump or something to fill it?

Thank you again for your help.

D.J.
.

[TMB_540i]

I use a manual marine type pump. It fits on the top of a quart bottle. I am sure there are other ways to fill it or top it off but this works well for me.

[John in VA]

Lubro-Moly makes a radiator flush product (from BavAuto or BMP, but maybe locally) that you add, then drive around for a day or two, remove/flush and then add your o-fficial BMW or M-B coolant plus distilled water.
Be sure to remove the block drain (if your car has one) under the exhaust manifold to get all the spent fluids out!

[old skool]

Pelicanparts.com has a great write up on this in their tech section. Check it out.

[mlytle]

Hello:

Does anyone have the proper procedure for radiator coolant flush? Is it just as simple as draining the radiator and refilling it with fresh coolant? Or should I need to follow more steps to flush out the rest of coolant?

Also, how do I check the oil level in my diff?

Thank you everyone for your help in advance.

D.J.
.

quick version:

turn heater on, run car.
stop car, let cool a little so you don't burn yourself.
remove coolant fill cap.
open radiator drain.
remove engine block drain plug. (under exhaust manifold)
collect all the coolant that rains down everywhere. one of those plastic kiddie pools works great for this function.

plug all the holes back up.
refill with distilled water.
run car until warm.
stop car.

drain everything again, plug all the holes (use new crush washers)

refill with proper coolant mix.

bleed air from system.

you really should get a bently manual for your car and follow those instructions in detail. draining the radiator alone only gets about 1/3 of the coolant out.

checking diff is easy. remove upper plug, stick finger in hole. oil level should be at bottom of hole edge.

marshall

[madkow70]

thank you sir for the detail help. ^^
i'm gonna go get myself a bentley manual as well.
i appreciate your help.

[mlytle]

thank you sir for the detail help. ^^
i'm gonna go get myself a bentley manual as well.
i appreciate your help.

your welcome...those procedures are almost second nature now...race car needs cooling sys flush twice a year and diff check every weekend...and then there are the two street bmws....

[M-technik-3]

Amazon is a great place for the service manuals too.

[slantsixm3]

Marshall, great suggestion about the kiddie pool! They probably think you are kidding, but I'm gonna get one next time. Tired of taking coolant baths and trying to mop it up before the dog comes sniffing around!
Great tip, thanks.
- Joel

[mlytle]

Marshall, great suggestion about the kiddie pool! They probably think you are kidding, but I'm gonna get one next time. Tired of taking coolant baths and trying to mop it up before the dog comes sniffing around!
Great tip, thanks.
- Joel

not kidding, it is cheap and works great! and spring is the time to get one while they are in stock at hardware and toy stores.

then cut the bottom off one of the empty gallon jugs of distilled water and use the jug as a scoop to move the used coolant out of the kiddie pool into containers.

[AlfaEric]

Marshall, great suggestion about the kiddie pool! They probably think you are kidding, but I'm gonna get one next time. Tired of taking coolant baths and trying to mop it up before the dog comes sniffing around!
Great tip, thanks.
- Joel

Kiddie pools have plenty of uses.

---Eric

[Scany]

Hi guys,

I understand the engine coolant drain plug is under the exhaust manifold, but I can't find it. Does anyone have a picture? The Bentley manual shows a picture, but I still can't locate it. I feel a little stupid not finding it, and I don't want to unscrew anything unless I know what it is.

I got the M52TU engine.

[Scany]

I found it this weekend. What set me off was that is was a 6mm hex bolt. The pictures I've seen has shown a regular bolt.

I took a picture that's shown on my blog:
http://skandsen.blogspot.com