How can I tell how old my cooling system is?

Wow. Feedback from the man himself! Many thanks Bob !

p.s. The only one I'm aware of is the Zionsville. Are there other versions of the alum housing?

Originally Posted by Mack

Wow. Feedback from the man himself! Many thanks Bob !

p.s. The only one I'm aware of is the Zionsville. Are there other versions of the alum housing?

The man? Hahaa, just to be clear, Mack, I'm not the guy in the video. I found it on You Tube, thought it was great, and posted here.

my cooling system was replaced by the first owner just a few years after it was brand new... in 05... ive got the tank in my hand for this weekend... but ill be doing the rad also in the next few months..

then ill be eye'n that aluminum setup i can easily justify a grand for a rad and tank that will outlast us all...

so what is the purpose of that plastic pin in the radiator fins????

few days ago i was shocked that some foreign plastic is stuck in the fins. to my horror it wouldnt come out so i got off the top (tiny bit of the plastic end still in there) and it stressed me out a ton because i spend a ton to refresh my suspension and cant spend another grand to redo all the coolant components....

this piece freaks me out considering the "fragility" of the oem radiator....

Originally Posted by mifesto

so what is the purpose of that plastic pin in the radiator fins?

Dunno. There 'was' a thread specifically on that pin somewhere. Somebody came up with the suggestion it's some sort of factory inventory code.

It's not on the replacement radiators; so, for us, it only serves as a reminder of an original radiator (something very dangerous at this point in time of the E39 build cycle).

Originally Posted by mifesto

this piece freaks me out considering the "fragility" of the oem radiator....

Why? It's not functional.

In fact, the aluminum part of the admittedly fragile Behr/Nissens radiator is actually quite robust. See details here:
- Behr radiator and Behr/Heat expansion tank autopsy (1) (2)

Here's another date-stamp clue from this thread today:
- E39 (1997 - 2003) > Genuine BMW Expansion Tank

Originally Posted by uncmozo

Notice z168's BMW expansion tank has the date code and the aftermarket one doesn't. The date code is the round circle with the '10' inside -'2010'. The dots around the edge of the circle represent months - 8 dots = August. The machine operator adds a punch mark in the mold at the start of each new month. So, this tank was manufactured in August of 2010. The tank from gibo58 was manufactured in November 0f 2009. This allows for trace-ability of defective parts.

By way of cross reference, a wonderful set of pictures was taken today of cooling system parts removed from an E39 that are relevant to determining the dates of all your cooling system parts:
- E39 (1997 - 2003) > manufacture dates on components'

From these date codes, the OP determined:

• Expansion tank (was original)
• Thermostat (had been replaced)
• Water pump (was original)
• Water pump pulley (had been replaced)

Awesome as always B.

I have a 97 528i looks like still have the original cooling system working at 124K mile. I got the car 3 and half years ago at 99K without knowing much about it. The car had three POs and no service record. It has been problem free for more than 3 years and recently the starter failed and also some oil leak from valve cover. I started to read in this forum and was able to replace the starter and the valve cover gasket myself thanks to the information here. Now the cooling system is making me awake at night. The more I read this forum, the more I worried. The car does not overheat but all components of the cooling system appears to be original. The radiator label does not have a date on it, but I appears still to be original based the information I read here. The upper radiator hose has a 97 marker on it. I have no idea on the thermostat and water pump but the coolant in the expansion tank is very very dirty. It is cloudy and looks like brown or rusty. I plan to do a complete system overhaul when the weather getting a little bit warmer.

Just shot a photo of my date coded OEM radiator label. Here it is: "29/04/02" So with 135,000 miles and just under 10 years, I may be in the running for longest-lived OEM Behr cooling system.

Now - I need to start procuring new parts, as by all accounts I am living on Way-borrowed time!!

I agree, man. Order that new radiator STAT! Other parts are probably just as old.

How can I tell how old my cooling system is?

When driving, if you start seeing hot, dirty antifreeze shooting over your left shoulder, it's too old.

I too have what I think is an original first year radiator and expansion tank (if the green canister in the attached photos is the expansion tank). The radiator sticker has no date. The green canister has "96" in a raised plastic circle. Also, as bluebee pointed out using a photo, my radiator has a white plastic plug on the engine side of the radiator about six inches up from the bottom.

The car is at 137,000 miles and 15 years. I need to get these vintage pieces replaced!

I may have all of you beat on this one. I've had the car (98 528I) for about a month and a half now and my mechanic told me the radiator was still fine. That is until I saw this thread and wondered so I had to check, the radiator I have is still the original. Look at the picture, on the yellow tag I believe it states 10 12 97. I will certailny replace this radiator in Feb (once the funds come in) with the hoses and expansion tank (I believe its all original)

The car came with aluminum thermostat so I'm assuming the previous owner replaced it and I just replaced the water pump.

After the radiator gets changed, I should be able to sleep well at night.

Thank you all for the info on this one.

Originally Posted by Ninety-8 E3nine

on the yellow tag I believe it states 10 12 97.

I don't see that in the picgture.

Is it in the punched holes?

Its the yellow sticker on the bottom. The date is perforated.

jbarrow22 - I think if you snap a close up of your yellow sticker - as Ninety-8 E3nine did you may be able to see through the perforations your actual build date.

Yes, I agree, you two both have me beat! But I'm starting to search through rockauto and other sites to collect the needed parts. Would rather not wait for a failure!

Originally Posted by Turbo_525

jbarrow22 - I think if you snap a close up of your yellow sticker - as Ninety-8 E3nine did you may be able to see through the perforations your actual build date.

Yes, I agree, you two both have me beat! But I'm starting to search through rockauto and other sites to collect the needed parts. Would rather not wait for a failure!

I strained to read the green tag and could not. I'll have to get a smaller camera to snap a closeup.

I called my mechanic, Vladimir, and told him the age of the system and asked about a replacement. His quote was about $600 using Behr/BWM/OEM. All other front-of-engine parts (pulley, tensioners, belts) have been replaced in the past year.

Turbo 585 - What kind of radiator are you going to get? I'm debating between Behr and Nissens. I found a Nissens for only $136 (I cant remember the website but I'll search it again) but I'm kinda skeptical as to why its so cheap. Maybe too many defects that they want to phase it out?

Do you have any other brands in mind? (Except Zionsville, a little too much for my budget unless theres a cheaper same quality version)

Originally Posted by Ninety-8 E3nine

The date is perforated.

They perforate the sticker while it's on the radiator to fully ensure that it will eventually leak on you.

So far have only found Nissens, however I prefer OEM and will keep looking until I find such. I agree Zionsville is the best, but I have to insure I will commit to keeping the car long-term if I go that route. Seems solid enough, it may just be worth the $1200 or so!

Partsgeek has OEM radiator listed at 171.94 if that is what you are looking for.

This thread discusses the sanded down BMW markings:

Originally Posted by BM109R

I don't know. Did I get played? My expansion tank has a sticker that says 'Made in Germany' and there seems to be an area below sanded down.

Originally Posted by cn90

Only 3 items have date stamped on them:
- Radiator: date stamp is usually on passenger's side
- Hoses should have date of mfg on them.
- Fan Clutch date is kind of hard to read in situ because it is behind the fan clutch. Much easier if you remove the Fan Clutch and look at the date.

If you have courage and energy then look up cooling overhaul for V8 by "BlackBMWs" on bimmerforums.

Then Best is to ground the car for a week, remove all the parts in the cooling system for examination. Anything old, order online and replace them.
This way you can sleep well for another 70K or so.

The thermostat has a date code as well. I just had the rad expansion tank and fan clutch changed. I had documentation fron the original owner that the tstat and pump were changed. The mechanic said he checked the tstat and it had a date code of 09/09. Document said it was changed in 2010. Which makes sense Not sure where on the stat to look but it's a very reputable indie BMW shop