can i save my m50 radiator?

[ryan roopnarine]

some background: about 5 months ago, my m50 powered 525i developed a rather large rad leak after a belt pulley came off. the car would use one resevoir of liquid every 50 miles. i assumed that the rad had some internal damage from the belt drive colliding with it. i was driving another vehicle at the time, so i only used the vehicle to run errands. cut to the present.....


i determine that the leak is coming from the expansion tank side of the radiator. i pull the radiator and see that the expansion tank is warped, and that the base o-ring is fitting like a very loose rubber band, as i can pull it on and off with two fingers to roll it. the top o-ring still fits very well, however. my concern is not with the tank or the o-ring.......

marzikfar?'s pics don't work anymore, they worked last week. i was going to illustrate with them what the issue is.
i can't figure out where the @ key is on my cell-phone, so i can't email the picture to myself to show you all. i'll try to illustrate what the issue is with ascii art.





the crack is in no danger of compromising the radiator itself, it would just affect the rigidity of the tank holder.

anyone want to take a swing at it? the radiator does not leak from any other place. stupid question, i know. ideally, would like to buy a new tank, put it in, and be good to go.

[Bin_jammin]

some background: about 5 months ago, my m50 powered 525i developed a rather large rad leak after a belt pulley came off. the car would use one resevoir of liquid every 50 miles. i assumed that the rad had some internal damage from the belt drive colliding with it. i was driving another vehicle at the time, so i only used the vehicle to run errands. cut to the present.....


i determine that the leak is coming from the expansion tank side of the radiator. i pull the radiator and see that the expansion tank is warped, and that the base o-ring is fitting like a very loose rubber band, as i can pull it on and off with two fingers to roll it. the top o-ring still fits very well, however. my concern is not with the tank or the o-ring.......

marzikfar?'s pics don't work anymore, they worked last week. i was going to illustrate with them what the issue is.
i can't figure out where the @ key is on my cell-phone, so i can't email the picture to myself to show you all. i'll try to illustrate what the issue is with ascii art.





the crack is in no danger of compromising the radiator itself, it would just affect the rigidity of the tank holder.

anyone want to take a swing at it? the radiator does not leak from any other place. stupid question, i know. ideally, would like to buy a new tank, put it in, and be good to go.

If you've got a swollen o-ring in your radiator, I'd drain the coolant and look at it. That's usually a sign of oil in the coolant, as oil will almost instantly make an o-ring swell up.

[Ross]

We all know how well our cars tolerate overheating.
Running around with a known sick radiator is just asking for it.
My advice is to shop hard for a new one rather than have us advise you on head gasket replacement.

[ryan roopnarine]

oh wow.

browzin' the autohauz, it would appear that the nissens are already "pre-cracked" along that line. tank warpage must have pulled it apart a little bit more.

look at the bottom of the white expansion tank, and move right, towards the brass fitting. that o-ring is known to fail to begin with, was already leaking a little bit when the belt came off. this makes me want take my chances with buying the $30 expansion bottle from them, and having the radiator leak/pressure tested somewhere in this case.

[RobPatt]

...i'm really wondering how many ba'zillion miles you have on that car!
Good on ya for it, but just remembering how much driving you talk about, oil analysis, etc...

my thoughts are if you still have that second car you mentioned, give the $30 tank a try... but if the E34 is the main ride... go for broke and get the new nissen or behr.... think i recall winfred or someone recommending www.radiator.com.

good luck.

[whiskychaser]

look at the bottom of the white expansion tank, and move right, towards the brass fitting. that o-ring is known to fail to begin with

Think you might have just solved a problem for me. Looking at
http://www.realoem.com/bmw/showparts...99&hg=17&fg=05
there only seem to be one 'o' ring at the bottom of the bottle (no. 3). Is this the one you mean or is there another one? Apologies for crashing your thread. Search button is on strike

[ryan roopnarine]

Think you might have just solved a problem for me. Looking at
http://www.realoem.com/bmw/showparts...99&hg=17&fg=05
there only seem to be one 'o' ring at the bottom of the bottle (no. 3). Is this the one you mean or is there another one? Apologies for crashing your thread. Search button is on strike

the one responsible for leakage is the one you mention. there is an o-ring on the level sensor, and one not pictured which is attached to a neck on the expansion tank.

[ryan roopnarine]

it's not that i am going to try to wring another 100k out of this radiator, it is just that i'm about to drop (more than) the cost of a replacement radiator on a pre-emptive new heater core unit (ebay radiator is about 20$ cheaper than a heater core). and want to get two or three months out of this guy before i spend money again. i've waited two years to do the heater, and i know of a source that actually has the core needed for my month/year production core in stock, so i'll be buying that in the next day or two.

[shogun]

this one is also from an E34 and works already a long time.
A copper coupling and 2-component glue (this kind of chewing gum stuff, where one has to put 2 different parts together and then mix it by hand, do not know that name in English)

[DanDombrowski]

When it has to do with plastic or aluminum cracks and sealing, my methods are:

1 - Try JB weld
2 - replace.

So, try the JB weld. If that doesn't work, I can't think that theres any method of repairing the crack thats worthwhile.