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madkow70
04-26-2006, 09:28 AM
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
04-26-2006, 11:18 AM
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
04-26-2006, 11:38 AM
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
04-26-2006, 09:10 PM
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
04-26-2006, 11:08 PM
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
04-27-2006, 07:39 PM
Pelicanparts.com has a great write up on this in their tech section. Check it out.

mlytle
05-01-2006, 10:57 AM
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
05-01-2006, 08:44 PM
thank you sir for the detail help. ^^
i'm gonna go get myself a bentley manual as well.
i appreciate your help.

mlytle
05-01-2006, 09:33 PM
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
05-02-2006, 09:21 AM
Amazon is a great place for the service manuals too.

slantsixm3
05-02-2006, 05:31 PM
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
05-02-2006, 05:47 PM
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
05-02-2006, 07:08 PM
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. :wink:

---Eric

Scany
10-19-2006, 01:37 PM
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
10-23-2006, 11:38 AM
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

mlytle
10-23-2006, 04:14 PM
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

those sneaky germans.....:-)

glad you found it. rest of the job go ok?

Roy
10-23-2006, 07:58 PM
2 more tips on differential checking/filling, not previously mentioned:

1. Facom (a French tool manufacturer) makes a low profile 14 mm 3/8" drive socket that will fit in the tight space afforded on an E36 differential. Griot's Garage special-ordered it for me. Part number D.107-14.

2. Make sure you can get the upper (fill) plug loose before you remove the lower (drain) plug.

-Roy

Scany
10-23-2006, 09:40 PM
those sneaky germans.....:-)

glad you found it. rest of the job go ok?

Yeah, it acctually went very well. Thanks for asking :) I should have had that idler roller to replace also, but eh, a reason to do it again some other time.

Now I really need to get to the bottom of that rythmic sound from the wheels..

shortyb
11-05-2006, 10:41 PM
Don't have a kiddie pool? Using it for something else? (beer cooler perhaps?). Here is something I have done a few times and it keeps coolant out of my eyes/ears/nose etc. when draining the engine block. Take a 2 foot section of 1 1/2 inch corrugated flex hose (same kind used for sump pump discharge hoses) and push it up between the steering rack boot and control arm. Push it up until it is against the engine block drain, the fit between the boot and CA will hold it in place. Make sure you have broken the drainplug free beforehand. Now reach up with one hand and pull the hose back slightly, enough to get a thumb and finger in there to turn the drainplug. Keep the hose as close as possible while turning the drainplug. When the drainplug is free, it will travel down the hose along with the coolant and into the drainpan you have hopefully put underneath. Once drained, retreive the drainplug and button everything back up. Simple.