Overheated: What Should I Replace?

My wife just drove our '02 330i while it was overheated. She's not sure how long she drove it that way, maybe a couple miles (which I know is more than enough). When I tried to start it after she got home (maybe that wasn't smart, but I wanted to see what it did) the temp needle immediately pegged to the right, the engine clicked loudly, ran rough, and then stalled. I was certain it was DOA.

However, I went out the next day and it started fine with the temp needle right in the middle. I topped the water off and bled the coolant then took it for a short drive and it had plenty of power and drove smoothly for a 30 minute drive. Water is steaming out of a crack in the side of the radiator, but I know that's an easy fix.

I had known there was a slow coolant leak before, but I couldn't tell where it was coming from so I recently replaced the Thermostat, Water Pump (with an EMP Stewart), and both hoses. That didn't solve the leak, but it was very slow so I procrastinated on replacing the radiator and expansion tank (kicking myself now.)

Questions: When I replace the radiator and expansion tank, should I repair the following?:

1. Since it over heated after those repairs, do I still need replace the thermostat even though it's almost new? (I know with older engines this was always advised, but the thermostat seems to be operating normally.)

2. Should I tackle the fan clutch while I'm at it?

3. Do I need to change the oil or should the fully synthetic stuff be okay with the brief overheat? (I changed it less than 1k miles ago.)

4. Would anything else be damaged? Please don't say the new $200 water pump.

5. Is there still a good chance that the top end is fried and I would just be wasting my money on all of the above repairs?

Thanks gang. Chris

be sure to search or check the stickied threads:

http://forum.e46fanatics.com/showthread.php?t=914109

Thanks. I wish I had read this thread a few months ago. Now, unfortunately, I'm looking for what to do when these things have already happened.

You'll know if your head gasket blew and head warped pretty soon after the overheat, if not immediately.
If your engine is ok then just solve the leak (radiator)

Your thermo, WP, & rad. hoses should be ok.
Replace radiator and expansion tank (get a NEW cap with it), asap.
While you're there do fan clutch and fan blades, plus all pulleys and belts. Probably a good idea to get a new auxiliary temp. sensor (for the lower rad. hose, if you haven't already). Fill with BMW coolant and re-bleed.

Report back.

I was in a similar situation a few months ago...

http://forum.e46fanatics.com/showthr...202&highlight=

My car ran ok for the first days after replacing expansion tank and then every thing started.... so before changing anything I would suggest to drive the car a few days and see how it behaves.

Good Luck

The Engine.....

Yup, I can't see the engine still being serviceable long term.

Sell car now!!
Preferably to an undeserving high schooler.

Do a leak down test. If pressure holds, and your coolant level doesn't rise while you're doing the test, you're probably fine.

If it does leak, time for a new engine.

Replace the wife

^
That's a bit harsh..

You're looking at $400-500 in parts and another 80-110k miles of reliability of the cooling system.

Originally Posted by scrace

You're looking at $400-500 in parts and another 80-110k miles of reliability of the cooling system.

That's to replace cooling system parts. This guy needs to find out if his engine is toast, or spending $400-500 on cooling parts for a toasted engine probably wouldn't do him much good.

Some people think I'm harsh or trolling for telling some new members about the cooling system when they post "what color" or "how wide" threads...

Now you know why.

(As if the other 8,000 threads where people say "I wish I would have seen this information earlier." weren't telling enough)

The fight continues. Good luck, OP.

It's a good fight nonetheless, Mango.

Anyway, so what color and how wide? I'm curious to know your thinking on that!

I would just drive it a little, short trips, few times a day next few days. See if any lights come on or anything else bad happens. If the light comes on then you'll at least have codes to give you a guide to what else might be wrong. If nothing pops replace the cooling system and hope everything else is fine.

Check your anti-freeze

Sent from my LG-E739 using Bimmer App

Originally Posted by mkodama

Do a leak down test. If pressure holds, and your coolant level doesn't rise while you're doing the test, you're probably fine.

If it does leak, time for a new engine.

+1

Sound advice

Originally Posted by dmax

It's a good fight nonetheless, Mango.

Anyway, so what color and how wide? I'm curious to know your thinking on that!

Black. About 8.5 inches.

(What! talking about plasti-dipped stock rear M68 wheels!)