Expansion tank good. Radiator not good. - E46Fanatics E46 BMW Social Directory E46 FAQ 3-Series Discussion Forums BMW Photo Gallery BMW 3-Series Technical Information E46 Fanatics - The Ultimate BMW Resource BMW Vendors General E46 Forum The Tire Rack's Tire Wheel Forum Forced Induction Forum The Off-Topic The E46 BMW Showroom For Sale, For Trade or Wanting to Buy

Go Back   E46Fanatics > E46 BMW > General E46 Forum

General E46 Forum
This is the place to get answers, opinions and everything you need related to your E46 (sedan, coupe, convertible and wagon) BMW!

Thread Tools Search this Thread Rate Thread Display Modes
Old 05-03-2016, 02:41 PM   #1
Registered User
Join Date: May 2016
Location: Dallas
Posts: 3
My Ride: 2002 325i
Expansion tank good. Radiator not good.

2002 325i

Just got this car. Coolant was low in the expansion tank. I filled it up, ran the car with heater. Filled it up again. When I stopped the second time, there was coolant steaming/spitting out of the top of the connection where the upper radiator hose connects to the radiator and the expansion tank was empty.

When I filled the expansion tank this time, coolant started pouring out of that (bottom) of the upper radiator hose connection. The hose connector at the top of the radiator was backed off about ¼ inch. From the forums, it looks like I need a new hose that is tight. This one is not. So, I’ll get one of those.

I took the hose off completely and tried to run water through the radiator to see if it would come out the engine. The radiator would not take any water from a garden hose.

I put the hose in the expansion tank. Water/coolant started pouring out of the engine where the upper radiator hose would be. Tried the radiator again. Wouldn’t take anything. Expansion tank again, water flowed right away. I put the hose back on, filled the expansion tank. Same thing. Water pouring out the top connector.

There was minor sediment build-up on the outside of the radiator at the connector. Minor abrasions. Felt around in the radiator with my finger and it felt dirty…like some random deposits/caked here and there.

I am getting the radiator fill light periodically but not consistently but the temp gauge never gets above halfway. Periodic but inconsistent interior heat from heater. Seems like the radiator is blocked and it won’t let coolant in. Doesn't seem like a flush would do any good if nothing is getting into the radiator. Am I missing something obvious? Is the next step a new radiator (besides the upper radiator hose)? I’ve worked on my Hondas for 20 years and am comfortable with them but I don’t know much about BMW.
dromedary is offline   Reply With Quote
Old 05-03-2016, 02:51 PM   #2
Registered User
Join Date: Aug 2006
Location: Las Vegas
Posts: 1,790
My Ride: 2003 325i
Transmission: Autotragic
Welcome to the E46 BMW community (if this is your first).

Give this thread a read and post any questions you might have.

I'm just here to change the world.
BMW Wiki: http://www.bimmerfest.com/wiki/index.php

2016 Beheadings in Saudi Arabia: 92.
swordsman11868 is offline   Reply With Quote
Old 05-03-2016, 02:58 PM   #3
Registered User
Join Date: Feb 2014
Location: OC, CA
Posts: 134
My Ride: '03 325CI 5-Speed
Definitely replace the expansion tank... from reading around here, it's pretty much enemy #1 and the single part that is most prone to failure. Mine somehow went 125k without exploding, but as soon as I saw it was original I replaced it the very next week (along with the entire cooling system). I plan on replacing the whole cooling system every 50k-75k, which is basically every 5 years.
firehawk is offline   Reply With Quote
Sponsored Links
Old 05-03-2016, 03:00 PM   #4
Registered User
Join Date: May 2016
Location: Dallas
Posts: 3
My Ride: 2002 325i
Thanks swordsman. I didn't see anything there to address this specific issue but I will repost over there.
dromedary is offline   Reply With Quote
Old 05-03-2016, 05:05 PM   #5
Registered User
Join Date: Mar 2016
Location: Delaware
Posts: 227
My Ride: 2000 323i Gold 5spd
Most people will tell you to replace the entire cooling system in one shot. I got a behr radiator for a little over $100 and it seems to work great. Most non oe style radiators will not line up right with expansion tank mounting bracket.
KawiNinjaZX is offline   Reply With Quote
Old 05-03-2016, 06:13 PM   #6
Registered User
Join Date: Mar 2013
Location: Phoenix
Posts: 888
My Ride: 2005 M3 ZCP
If you do decide to do a complete cooling system replacement, and you should, pay particular attention to the radiator you buy. See my link in my sig.
*KJ---Don't Believe Everything That You Think! *

Buyers Guide
Nuts and Bolts
Behr Radiator Issue
Clean Your Dirty Wheels

2005 M3 ZCP (KJ's Ride)
2003 Touring 325 XiT (Mrs. KJ's Ride)
2004 Coupe 325 Ci (In Storage)
KaktusJaque is offline   Reply With Quote

expansion tank, flush, leak, radiator, upper radiator hose

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Censor is ON

All times are GMT -5. The time now is 06:23 PM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
(c) 1999 - VerticalScope Inc. All rights reserved.