Radiator Pinhole Leak?

[B Rod SRT]

This is a picture of the back of the radiator on the drivers side of my 540i. Would this be evidence of a pinhole leak?

http://i17.photobucket.com/albums/b60/brodgsr/IMG_20121105_085450.jpg

The Check Coolant Level warning came on for the first time with this car, this morning. There are no puddles under the car and the operating temp has been normal. I haven't checked the actual level in the overflow tank because the car is still quite warm.

[edjack]

No doubt a leak. Why not pull the shroud and investigate?

Could be a precursor to a catastrophic failure.

[bkgreene39]

Possibly leaking at the 90 degree elbow hose, you can replace that part without replacing the entire radiator if that is indeed where the leak is from.

[B Rod SRT]

Thanks guys. I'll pull the shroud on my lunch to get a better view of what's going on.

Alright, here's with the shroud pulled back to show the radiator.

http://i17.photobucket.com/albums/b60/brodgsr/IMG_20121105_095051.jpg

To me, it looks like its coming from that 90 degree fitting. There's definitely corrosion on the metal at the top of that seam, but it's probably from the coolant coming out of that fitting. Is this a normal issue?

[sealbeach740]

To me, it looks like its coming from that 90 degree fitting. There's definitely corrosion on the metal at the top of that seam, but it's probably from the coolant coming out of that fitting. Is this a normal issue?

Yep. Very common, and lucky you, a very cheap fix. Be carefull pulling the old plastic elbow off, it's easy for it to break apart (if it's old enough) & you don't want any bits of plastic falling into the radiator.

[B Rod SRT]

If that part is failing now, would that mean the rest of the radiator is getting ready to do the same? I'm wondering if I should just replace the entire thing so I don't need to worry about it. However, if people have replaced that elbow and had thousands of miles with no further issues, I'd rather save the money for now.

[john@eac]

I would go with the elbow and just keep an eye on the radiator.

[JimLev]

I would go with the elbow and just keep an eye on the radiator.

+1, if the radiator is original (1999?) and you intend on keeping the car for a few more years you may want to order a radiator now just to have on hand for the day you really need it.

[B Rod SRT]

The PO definitely replaced the radiator some time in its past.

[Mike36]

Replace the radiator soon. If you're on a budget, Pepboy's surprisingly has one for $130 with a 1yr warranty.

[Vipsa]

Replace the radiator soon. If you're on a budget, Pepboy's surprisingly has one for $130 with a 1yr warranty.

Don't do that. There's only two radiator worth putting in an E39 the OEM Behr and the zionsville. The OEM Behr ones are available at autohausaz for $138 with free shipping.

[FlipredE36]

I've also heard good things about Nissen. I've had Nissen in other cars and they worked great.

[Justin517]

Don't do that. There's only two radiator worth putting in an E39 the OEM Behr and the zionsville. The OEM Behr ones are available at autohausaz for $138 with free shipping.

The "OEM" behr one for that cheap supposedly isn't the same as the behr one you get from a BMW dealer... there have been people who have had behr replacements go bad in 6 months.

For a while the general consensus was that if you want something that lasts buy from a dealer (online dealer even) and spend the $300-$450 but it seems those can fail also.

I'm almost of the mind set that I will just buy the cheapest one with a 1 year warranty and just plan on replacing it every 1.5-2 years if it lasts that long.

[dmw525i]

03 525i: Had to replace my rad back in May. At time I had 130k plus on Od. Month later I had to replace expansion tank. Now just turned November and my replacement rad has a leak. The shop I use has been trying to convince me that this not a common problem on 5series. However after reading forums I'm doubting what they have been telling me.
Their new approach to this new leak in this new Rad is that I may have too much pressure in the engine which means a new head gasket will be needed. My question to you all is how much of this should I believe or is it a possible poor quality Rad like I've been reading about?? Please let me know I love the car but may have to dump it; tired of this unreliablity.

[240sxguy]

Most likely a junk radiator. The OEM systems use a 30 psi or so cap, that's a LOT of pressure.

[B Rod SRT]

So I decided just to replace the 90 degree fitting. So I pulled the fitting out of the radiator. Here's how it came out.

http://i17.photobucket.com/albums/b60/brodgsr/IMG_20121114_114826.jpg

The o-ring is definitely bad. However, 2 pieces of plastic broke off. Do I need to pull the damn lower hose off to get them out, or should I not even worry about it?

[240sxguy]

If you look in the hole can you see if the piece sank? Mine did the same dang thing when I removed it. You really don't want to leave that in there, god knows where it will end up. If you pull the upper hose can you rescue it?

[B Rod SRT]

I looked in the hole with a flash light and couldn't see a damn thing. After a quick, super technical test of throwing the old fitting in a cup of water, it does not float.

Being on the side of the upper radiator hose, there's no way the pieces could make it to the other side and travel into the motor, right?

[240sxguy]

Honestly, I am not sure. Best case it blocks a row of tubes I suppose. My paranoia with these damn cars would have me tearing the entire thing apart trying to retrieve it.

[B Rod SRT]

Damn, I'm so torn as to what I should do. I want to just put the new fitting in and now worry about it, but I feel like I should pull the radiator, get the pieces out, and refill coolant.

[240sxguy]

Your call. You may be able to get that chunk out with a hose hooked to a shop vac after you have at least drained the system.

[JimLev]

Damn, I'm so torn as to what I should do. I want to just put the new fitting in and now worry about it, but I feel like I should pull the radiator, get the pieces out, and refill coolant.

You can do that if you want to.
Even if a piece of plastic did block one of the lower cross tubes you would be loosing less than 1% of the radiators cooling capacity.
Just put it all back together and you'll be fine. You are not the first person this has happened to.

[rdl]

Most likely a junk radiator. The OEM systems use a 30 psi or so cap, that's a LOT of pressure.

I beg to differ regards the effect of the rad cap. Please see this link for my thoughts on why our engines do not operate at high pressure.
http://www.bimmerfest.com/forums/showpost.php?p=6662788&postcount=7

Regards
RDL


You can do that if you want to.
Even if a piece of plastic did block one of the lower cross tubes you would be loosing less than 1% of the radiators cooling capacity.
Just put it all back together and you'll be fine. You are not the first person this has happened to.

This is good advice.

B Rod - even if you got extemely unlucky and the missing pieces shattered into fines and a few bits got through the rad, the worst that could happen is that a tiny piece might lodge in heater control valve. But it would then almost certainly be flushed through with no harm done the next time the valve opened up.
The coolant system is not like the oil circuits with small diameter passages at risk of plugging causing catastrophic damage due to blocked flow.

Regards
RDL

[B Rod SRT]

Thanks for the advice guys. I should have just waited. Ended up pulling the radiator, and nothing came out anyways. Now I just get to buy more coolant and bleed the whole system.

[240sxguy]

I beg to differ regards the effect of the rad cap. Please see this link for my thoughts on why our engines do not operate at high pressure.
http://www.bimmerfest.com/forums/showpost.php?p=6662788&postcount=7

Regards
RDL



Interesting read, I am aware of how a cooling system works and the principals behind it. I was not aware, however, that we were only seeing 10psi of pressure at 100c. I assumed bmw would have been a little more conservative on the cap rating, but I may be wrong.

[RebeccaR]

my radiator overheated because frankly, i didn't know what i was doing and neglected to put coolant in my car. so this elbow exploded and then my car died. now im learning the hard way. there is little left of the piece you described had come off partially. i am looking to fix this problem, but do not want to get a whole new radiator, however is it necessary?

[rdl]

my radiator overheated because frankly, i didn't know what i was doing and neglected to put coolant in my car. so this elbow exploded and then my car died. now im learning the hard way. there is little left of the piece you described had come off partially. i am looking to fix this problem, but do not want to get a whole new radiator, however is it necessary?

The elbow can be replaced & it's a simple repair. The part # is 17 11 0 419 132. It will be ~$2 from a dealer.

However, if you lost all coolant and overheated the engine badly there is a risk of a headgasket failure which would be very expensive. I think your best bet is to replace the elbow, refill the cooling system (DIYs available - it's not rocket science, but more complicated than simply pouring in new coolant) then cross your fingers and hope there aren't any symptoms when you drive the car over the next few days. It would be worthwhile having the engine checked for a failed headgasket at a repair shop.

If the engine behaves itself for a few days &/or passes the test, have the entire cooling system inspected & probably overhauled. The rule of thumb is that a system over 100k miles is on borrowed time. The plastic parts in particular deteriorate with age. Again, lots of DIY's available so you can gain a feel for the time & expense involved.

BTW, the more likely sequence of events is the elbow broke, coolant leaked out and low coolant caused the overheat.

Regards
RDL