BMW Cooling System Refurb

Do the E39s require the cooling system replacement around 100k mi like some of the other BMWs? Are the V8 cars more or less susceptible than the I6s?

In reply to AngryCorvair:

My dad had a 2000 540i that needed a cooling system overhaul at about 60K miles. I think they're about the same as any BMW.

my buddies 98 540i needed it at 100k

The V8s are worse than the I6s for cooling system needs. Personally I don't know that I'd go more than 80k on the stock components and certainly at 100k I'd invest the time and money to avoid a potential overheat with warped heads...

I don't suppose there's any way to tell. My E39 M5 got a poke in the nose a while back and based on other components, I suspect it got a new radiator and fans at that point. The fans look very new. I'm trying to figure out what preventative maintenance I should do without replacing parts that are already pretty fresh.

Kieth, I would order the parts which can fail catastrophically and without warning such as expansion tank, upper and lower hoses. Metal impeller water pumps give plenty of warning before they fail. Pull apart the front end, check the pump for play and bearing growl, check the pulleys for the same and make sure the belts look good.

AC, I've used these guys for my BMW parts in the past. Great customer service and competitive pricing. You could price out a coolant system refresh with them to get an idea on the price of the parts required.

http://getbmwparts.com/

dyintorace wrote: AC, I've used these guys for my BMW parts in the past. Great customer service and competitive pricing. You could price out a coolant system refresh with them to get an idea on the price of the parts required. http://getbmwparts.com/

holy E36 M3, $700 DIY every 60 - 80k?

that includes: - radiator - upper hose - lower hose - reservoir - radiator cap - water pump - thermostat housing

did i miss anything?

If you shop around. i.e. Rockauto, pelican, etc. you can do this for cheaper.

I wouldn't go more then 100k without doing a colling system overhaul. I did mine for $400ish with everything listed in that DIY... You've just got to be smart about it.

You really should do the fan clutch as well - they tend to lock up and cause the fan to explode.Click for Fan Carnage And replace the temp sensor in the lower hose; the old sensor will not seal properly in the new hose and will leak soon after.

If you are uncertain about the age of parts, BMW does date stamp everything, so you should be able to figure out if things have been replaced or are still original.

AngryCorvair wrote: holy E36 M3, $700 DIY every 60 - 80k? that includes: - radiator - upper hose - lower hose - reservoir - radiator cap - water pump - thermostat housing did i miss anything?

You only do the water pump once - get a pump with a metal impeller. Unless you're anal, only replace the cap and radiator if they leak. The thermostat is integrated into the housing, so there's no shock to replacing that or the hoses. Buy your parts online and save 30-50% over dealer rates.

The components are all plastic to be light weight, and the plastic just doesn't stand up after years of heat cycles. Our E39 went about 7 years on the original bits before I replaced the thermostat, tank and hoses.

At the back of the head on the V8 there is are some hard to reach hoses that you should replace because when they break they are a huge pain to try to fix on the side of the road.

As far as the widespread panic over cooling components... replace the water pump and t-stat. Carefully inspect the condition of the plastic on the radiator where the hoses attach. If its not cracking/flaking and seems strong (like you can't break a chunk out of it with your thumb) then put it back in. Same with all the other plastic stuff. Supple is good, brittle is not. Check the fan clutch. If its toast buy one, if its not... don't. This stuff does not fail overnight... you can see it coming and plan for it.

Check the motor mounts. Catastrophic radiator failures and exploding fans are often caused by hoses yanking the bejeebers out of the necks and stuffing the blades into the plastic shroud when it dances around.

Try bimmerparts.com for decent prices and fast shipping.

In reply to AngryCorvair:

BMW doesn't know how to manufacturer cooling components or suspension bushings that last longer than an oil change.

02Pilot wrote: If you are uncertain about the age of parts, BMW does date stamp everything, so you should be able to figure out if things have been replaced or are still original.

That's exactly the sort of thing I need to know, thank you. I'll be doing some underhood snooping soon. And thanks everyone for the suggestions.

This is one area where owning the big daddy M5 instead of the 540i is going to sting - parts prices are usually double, and that seems to be the case with water pumps. Oh well, I can always pretend I'm buying parts for a Z8...

"You only do the water pump once - get a pump with a metal impeller. "

This is incorrect. I've worked on BMWs professionally for 6 years and BMW water pumps fail, regardless of impeller type. Plastic impellers become brittle and break and metal impellers shear away from their shaft.

With that said, your M5 should have normal radiator hoses with clamps(I'm pretty sure), instead of the plastic-ended quick connect hoses found on the other eights and sixes. These hoses shouldn't need preventative replacement unless they are softening. Just use judgement like you would on any other car.

Another source for parts is autohausaz.com - prices were always very good as was service, and I bet you get next day delivery to CO vs. the 3-4 days for me in NY. Dealer with BMWCCA discount usually isn't too bad for when you need it today.

Damn, all these discussions in BMW maintenance are making my head hurt. My 750 has 80k+ miles on it now and will hit 100k probably by the end of 2011 so I will be doing some work or talking to my local indy soon myself. I just hope a bunch of stuff fails before the 100k CPO warranty runs out vs. right after...

I have to shop online, I think the nearest BMW dealer is four hours away on the other side of the Continental Divide Same with Mazda. VW is only an hour and a half away.

But we have a Saturn dealer that just finished building a brand new shiny facility! Poor guy. Never even got the chance to put the sign up.

Keith wrote: This is one area where owning the big daddy M5 instead of the 540i is going to sting - parts prices are usually double, and that seems to be the case with water pumps. Oh well, I can always pretend I'm buying parts for a Z8...

Ouch -- I've been pleasantly surprised that the M tax isn't too high on my E36. Then again, it's no where near as specialized as an M5, either.

You can look for the coating of white on/around the cooling system. It literally looks crappy white spray paint. That is how you know it is about to go on the ones I looked at.

so the radiator isn't a typical "replace every 60k - 80k" part?

Depends on how peaceful you want to sleep. I'd go with inspect frequently and wait on the radiator. They have a habit of splitting at the plastic end tanks and more particularly having the plastic crack where the hoses attach. First signs of cracking or leaking replace. Keep an eye on that area and also keep an eye on the motor mounts - it is widely thought that the cracks there are due to excessive movement of the hoses from excessive movement of the motor, which if allowed to get bad enough can also lead to the fan hitting the radiator and shattering with expen$ive results.

Cone_Junky wrote: In reply to AngryCorvair: BMW doesn't know how to manufacturer cooling components or suspension bushings that last longer than an oil change.

The original radiator was still in my E30 at 210k when a deer went thru it. I JB Welded it and drove another 2 years before making it a race car.

The original radiator was still in my E28 at 215k+ when it went bye-bye

The original radiator was still in my E36 M3 (after 30-50k track only miles and 90k+ total)

The original radiator was replaced due to flaking at the neck in my E36 328is at 112k

The original radiator is still in my wife's E46.

I've never replaced an expansion tank. I have seen them fail in other people's cars but not often or at unusually low miles.

I replace the water pump and t-stat every 35k whether it needs it or not. Both parts together cost less than 7 quarts of Mobil 1 and take 45 minutes to install. You guys are silly with the fear. Just look around under hood for signs of trouble once in a while before you see coolant puddles.

I got my parts from bimmerzone.com.

Consider replacing the clutch fan with an electric. The OE fan is known to fail like a grenade and take a lot of stuff with it, including the hood.

Somebody makes an all aluminum radiator with a nice integrated shroud and electric fans included and mounted to the nice aluminum shroud. Very pretty piece. Expensive, but maybe worth it as it should last the life of the car. I don't remember who it was, but they were popular on bimmerforums.

I know the radiator was replaced in my car when it was totalled.. because nobody ever installed the sensor to turn on the electric fan (m44s use electric cooling fans) and it would overheat in traffic until I discovered why.

How old it is... I am guessing 50 to 60 thousand miles.

Our E39 is 9 years old and has 80,000 miles. Radiator was replaced at 15K miles due to an an accident, and the replacement is still good today. The expansion tank was original until about a year ago, when I replaced it because it had formed a small crack and started to leak.

Like any car, keep an eye on known trouble spots and replace things when they start showing signs of wear or age.

I don't know about the rest of you, but any part which is a "replace every 60k - 80k" part means I'll have to replace it once - maybe. How long do you keep your cars?