Help, Coolant tank leaking

[walt525tour]

I took my new old '95 525ita for a long drive yesterday, 1+ hour.
when I went out to drive it around the block with my son in law the coolant light came on.

We went back let it cool down and added some water, maybe too much water - filled it, oops!

Drove it home later, got home no coolant or water in the tank.

let it sit over night no leak on floor in morning.

added water again drove it , again no fluid in tank on return.

let it sit and idle filled tank with water again, no leak for about 5 minutes till it got warm, then noticed fluid coming out at seam at bottom of white coolant tank - not at the hose clamp. See picture

looked at dash , warning message check coolant and the tank is full but slowing leaking!

Then I check the forum and see something about bleeding the radiator - ! say what? !!
Will it stop leaking if I bleed it right? I fear not.
Is my radiator broke?
Is the tank replaceable?
Will all of this be explained to me if I buy a bentley manual?

What will it cost for me or someone else to fix it??

[walt525tour]

a thread at the bentley forum suggests that there is a O ring down there that may be leaking.

Anyone know how to get it all apart?

[walt525tour]

Hey, I'm still looking for help.
Anybody have a link for a good description of how to change/remove/repair the expansion tank on a 525?

[Torque]

I think it just prys off... don't quote me on that. I did it a few months ago, but I don't remember.

New expansion tank thing is going to cost somewhere around 50-70 and it is very easy to do youself... if you need a new radiator it will cost from 170 to 250 depending where you buy... I found some one eBay for 179.

www.bmwe34.net has some good info on how to bleed the system... i believe it's under troubleshooting.

Good luck bro !

[beautyland]

Experts say there are two types of radiators, one that leaks and the other that eventually leaks.

I am afraid to say that you need a new radiator. If this is automatic, there is a separate tranny coolant radiator that goes under regular radiator. It is easy to change but a messy job. I changed mine about a couple of months ago. search on this forum for links. Best of luck.

[Torque]

My 5er with a M20 engine doesnt have the additional tranny cooler radiator...the main radiator is divided somewhere inside and there is just a hose from the tranny that runs to the bottom part of it.

[walt525tour]

Well, my car is back up and running just fine now. -

My problem was the water pump.

I changed the coolant tank and it was still running hot on and off, kept bleeding it thinking that may be the problem. also the low coolant warning was lit.

Heard some strange noises so I decided to change the water pump sure enough plastic and cracked!! but not in pieces just cracked so that when it got hot it slipped

I replaced my fan shroud at the same time -driver side had deteriorated. And also put in a coolant level sensor, now everything is fine.

Oh yeah I also changed the oil & filter, that was a must do, after over heating the engine the oil smelled burnt.

it was a bugger to get the fan loose.

I saved the parts so maybe i'll post some pics later

hoping the overheating experiences didn't affect the head and gaskets.

Seems to be running great now.

[97alpineM3]

Good to hear everything is now running well.. so the plastic water pump propellar thing isnt just on 3-series is it..??.. some 5 series have the same problem... I didnt knwo that... hmm.. Thanks for the follow up on what the problem was... it helps when people follow up on their conditions...

Thank you

Les

[numberthree_]

yup.. i had to change the water pump on mine too.. that solved my overheating problem..

[Slvr e39]

My 98' 528i is now having problems, my oil temp gauge is messed up so that doesn't help the situation, but when I got home from school yesterday, I filled up my coolant because it was low, I came home today and checked it and it was at the same height as the day before BEFORE i filled it...not good

I dont see any leaks either

it is all getting fixed sometime next week tho