Yet another cooling system refresh, but with a kicker.

I haven't been around in a long time; sorry 'bout that. Too much stuff and not enough me.

Anyway, on Monday I was out running some errands. Totally uneventful. Pulled into my driveway, shut down and cart my errand stuff inside. Wife comes home about 5 minutes later and said that there is a huge flood emanating from under my car. Go check it and sure as hell, there was a pale blue stream heading down the driveway. Popped the hood and the overflow tank had about an 8 inch split. I set up a big fan to cool off the engine and went off to FCP Euro for a boatload of refresh parts. Started the install today, should finish up tomorrow.

The kicker? Previous owner had done a refresh EXACTLY 75,000 miles ago.

How about them apples?!

Ken...

Good story. Glad this happened on your driveway and not in the middle of nowhere. Hope you ordered the water pump as well. When I had my first e46 (1999 323i), I asked my Indy to refresh the cooling system. Fast forward some months, I decided to sell the car.

A guy from Houston (2.5 hours away) bought the car. He called me a couple of hours later, the car overheated outside of the city limits. He was cool about it (no pun intended). Just wanted to know if that happened to me before.

The culprit ? WP ... You guessed right. I looked at my invoice, that part was not replaced by my Indy.

Gotta love these BMW cooling time bombs. I had something similar happen in my old e36.

I was driving home one afternoon and rolled over 200k miles and was just so damn proud of that car for being so solid to me for all those miles. Pulled her into the garage, and said "good car" just as steam billowed out from the hood [emoji52]


FYI it's also a good idea to throw on a 1.4 bar expansion tank cap to avoid this happening again. It'll [hopefully] release the pressure before the expansion tank cracks.

Quote:

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Originally Posted by fredo

Hope you ordered the water pump as well.

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Ordered the "Mango" kit plus an alternator belt tensioner. And a gallon of coolant.

Quote:

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Originally Posted by ZHPizza

FYI it's also a good idea to throw on a 1.4 bar expansion tank cap to avoid this happening again. It'll [hopefully] release the pressure before the expansion tank cracks.

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I had the G.A.S. 1.2 bar cap on there when it blew. Those tanks really are a disaster looking for a place to happen. I'm starting to think that it might be a good idea to keep a tank and water pump "in stock".

Ken...

Quote:

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Originally Posted by kbcons

I had the G.A.S. 1.2 bar cap on there when it blew.

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Oh snap

Was it an OE or aftermarket expansion tank?


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Quote:

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Originally Posted by san

Was it an OE or aftermarket expansion tank?

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Previous owner was an ECS Tuning fan, so probably OE or OEM.

Ken...

Quote:

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Originally Posted by kbcons

Previous owner was an ECS Tuning fan, so probably OE or OEM.

Ken...

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If the cooling system was replaced as a kit from ECS tuning, it was an aftermarket tank.

Previous owner of my car had installed on of their kits and it lasted roughly the same mileage.

ECS also has BMW kits with BMW bits. I bought one the last time. Had a REALLY tough time with the prior cooling system refresh with aftermarket parts. Also, the ‘upgraded’ metal impeller WP self destructed on me.

Evidence:

https://uploads.tapatalk-cdn.com/201...dc754f973e.jpg

A balled up piece of metal just inside the cooling passages on the block the wife found.
https://uploads.tapatalk-cdn.com/201...27bd3545f6.jpg

Went back to OEM
https://uploads.tapatalk-cdn.com/201...c7a7e0db2c.jpg

Also replaced the radiator with BMW.

Good luck OP!

I have no way of knowing if the previous owner used an ECS kit or bought parts piecemeal. The water pump looked to be in good condition, but it got replaced regardless. I'll dig the old tank out of the trash later and see if there is a manufacturer's stamp.

Edit. The failed tank was made by Vaico. Can't really fault it. The thing lasted 75,000 miles, 70,000 of which was with a 2 bar cap.

That's one fine looking corpse of a water pump you got there. Get all the pieces out of the engine?

The "Mango kit" from FCP Euro is all OE/OEM or BMW parts, so I should be okay. Old radiator is a Behr. New one is Nissens.

Ken...

Damn I’m on borrowed time. Got a day off next week. Think I’ll be ordering some goodies and try to tackle it. How long should a refresh take? Don’t think I’d do the radiator, unless it’s highly recommended.


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Quote:

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Originally Posted by kbcons

I have no way of knowing if the previous owner used an ECS kit or bought parts piecemeal. The water pump looked to be in good condition, but it got replaced regardless. I'll dig the old tank out of the trash later and see if there is a manufacturer's stamp.

Edit. The failed tank was made by Vaico. Can't really fault it. The thing lasted 75,000 miles, 70,000 of which was with a 2 bar cap.

That's one fine looking corpse of a water pump you got there. Get all the pieces out of the engine?

The "Mango kit" from FCP Euro is all OE/OEM or BMW parts, so I should be okay. Old radiator is a Behr. New one is Nissens.

Ken...

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I would guess that yes, there are more bits inside somewhere. So far, no weird noises or behavior. I replaced the first one at about 60k(?) or so?

The last one was at 125k.

Quote:

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Originally Posted by joeybananaz18

Damn I’m on borrowed time. Got a day off next week. Think I’ll be ordering some goodies and try to tackle it. How long should a refresh take? Don’t think I’d do the radiator, unless it’s highly recommended.


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I wouldn’t worry too much about a radiator unless you’ve got some mileage on your car. Mine was still in decent shape, but since I was going to have the rest of the system off, I might as well do it. It was shiny. :)

I cant give you a good time estimate, cuz I’m real slow and methodical. I usually spread out the work over several days. And yes, I’m an old geezer.


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I'm thinking of spending a weekend doing it and taking my time making sure its all done right. I'm at 163K.

Quote:

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Originally Posted by joeybananaz18

Damn I’m on borrowed time. Got a day off next week. Think I’ll be ordering some goodies and try to tackle it. How long should a refresh take? Don’t think I’d do the radiator, unless it’s highly recommended.

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Take a look at the parts in the kit I linked above. That's a full refresh, including radiator. Remember that the radiator has plastic tanks which may (will?) crack with age. I really strongly recommend the 1.2 bar cap from G.A.S. The factory cap is 2 bar, which is WAY more pressure than necessary and will likely cause tank failures earlier than than we're used to.

I'm thinking that if I had my indie shop do the work it would be a full day for a seasoned pro if it goes well. I am not a seasoned pro. High mechanical aptitude, but not a pro. I spread it over three days, 3-6 hours per day. Mitigating factors: (1) Not pro, (2) Sick with some bug, (3) I'm an old fart.

Quote:

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I'm thinking of spending a weekend doing it and taking my time making sure its all done right. I'm at 163K.

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It is time.

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Postmortem and tips on a completed job, not necessarily in order:

• Thanks to 50sKid from YouTube for a his how-to vids and "Mango" from E46Fanatics. Gave me enough understanding to get it done.
  
  Get the front end safely up in the air because you will be under there.
  
  I bought a large concrete mixing tub at Home Depot ($13) to place under the front end to catch all the inevitable mess. Totally worth it.
  
  Only a couple semi-specialized tools required: a T50 Torx socket and an 8mm socket, both to fit your socket wrench. These are for the tensioners. The A/C tensioner is de-tentioned with the T50 Torx socket. The main serpentine belt is de-tensioned with the 8mm hex socket. That's the way it's supposed to be. Mine was T50 for both. Snap off the caps and check. The last thing you need here is a stripped out bolt head.
  
  Speaking of belts: Don't remove the serp belt until you carefully and accurately draw the belt routing on a piece of cardboard or some-such.
  
  Use a light coating of silicone grease on O-rings to ease installation. Do not use petroleum grease.
  
  You will hate installing a radiator. If you have not yet developed a profane vocabulary, you will. If you have one, you'll extend it.
  
  Be sure that block mating surfaces for the water pump and thermostat are clean before installing new.
  
  Get a gallon of distilled water and pour off 64oz into a clean container. Pour BMW coolant in the half full water jug to bring it back to a gallon, then pour the water from the container into the BMW coolant jug. Now you have your coolant all premixed and ready to go.
  
  Optional: A couple feet of 1/2 inch ID clear flexible tubing forced over the open bleed hole will aid in (1) seeing the bubbles you'll be looking for and (2) containing the mess and directing it to the tub or whatever under the car. Only used during the initial (cold) fill. Just be careful not to allow a siphon to start.
  
  When filling, pour in the coolant from the BMW jug first. Then before you move on to the other jug, stop and empty the old coolant into the BMW jug (for HAZMAT recycling) and clean & dry your mess catcher. Place the cleaned mess catcher back under the car and continue the fill. This is so that if you have a major leak you'll be able to re-use the caught coolant.
  
  Gently squeezing and releasing the upper radiator hose will help to get bubbles out.
  
  Once the initial fill is done, check for leaks at all fitting locations you changed out. Then start the car and let it idle to normal operating temp. Turn A/C off and heater all the way up with the fan on low. After it gets part way warm, check for leaks again. Once it gets to normal operating temp, again check for leaks. Shut down the engine and let it sit for a few minutes to really heat soak the coolant and build pressure, then check for leaks. Remember that the cooling system will see its max pressure shortly after shutting down the engine.
  
  If everything is good, let the engine cool down completely and check coolant level in the tank. Adjust as necessary.

I'm gonna go for a drive.

Ken...

Quote:

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Originally Posted by kbcons

Take a look at the parts in the kit I linked above. That's a full refresh, including radiator. Remember that the radiator has plastic tanks which may (will?) crack with age. I really strongly recommend the 1.2 bar cap from G.A.S. The factory cap is 2 bar, which is WAY more pressure than necessary and will likely cause tank failures earlier than than we're used to.

I'm thinking that if I had my indie shop do the work it would be a full day for a seasoned pro if it goes well. I am not a seasoned pro. High mechanical aptitude, but not a pro. I spread it over three days, 3-6 hours per day. Mitigating factors: (1) Not pro, (2) Sick with some bug, (3) I'm an old fart.



It is time.

=========================

Postmortem and tips on a completed job, not necessarily in order:

• Thanks to 50sKid from YouTube for a his how-to vids and "Mango" from E46Fanatics. Gave me enough understanding to get it done.
  
  Get the front end safely up in the air because you will be under there.
  
  I bought a large concrete mixing tub at Home Depot ($13) to place under the front end to catch all the inevitable mess. Totally worth it.
  
  Only a couple semi-specialized tools required: a T50 Torx socket and an 8mm socket, both to fit your socket wrench. These are for the tensioners. The A/C tensioner is de-tentioned with the T50 Torx socket. The main serpentine belt is de-tensioned with the 8mm hex socket. That's the way it's supposed to be. Mine was T50 for both. Snap off the caps and check. The last thing you need here is a stripped out bolt head.
  
  Speaking of belts: Don't remove the serp belt until you carefully and accurately draw the belt routing on a piece of cardboard or some-such.
  
  Use a light coating of silicone grease on O-rings to ease installation. Do not use petroleum grease.
  
  You will hate installing a radiator. If you have not yet developed a profane vocabulary, you will. If you have one, you'll extend it.
  
  Be sure that block mating surfaces for the water pump and thermostat are clean before installing new.
  
  Get a gallon of distilled water and pour off 64oz into a clean container. Pour BMW coolant in the half full water jug to bring it back to a gallon, then pour the water from the container into the BMW coolant jug. Now you have your coolant all premixed and ready to go.
  
  Optional: A couple feet of 1/2 inch ID clear flexible tubing forced over the open bleed hole will aid in (1) seeing the bubbles you'll be looking for and (2) containing the mess and directing it to the tub or whatever under the car. Only used during the initial (cold) fill. Just be careful not to allow a siphon to start.
  
  When filling, pour in the coolant from the BMW jug first. Then before you move on to the other jug, stop and empty the old coolant into the BMW jug (for HAZMAT recycling) and clean & dry your mess catcher. Place the cleaned mess catcher back under the car and continue the fill. This is so that if you have a major leak you'll be able to re-use the caught coolant.
  
  Gently squeezing and releasing the upper radiator hose will help to get bubbles out.
  
  Once the initial fill is done, check for leaks at all fitting locations you changed out. Then start the car and let it idle to normal operating temp. Turn A/C off and heater all the way up with the fan on low. After it gets part way warm, check for leaks again. Once it gets to normal operating temp, again check for leaks. Shut down the engine and let it sit for a few minutes to really heat soak the coolant and build pressure, then check for leaks. Remember that the cooling system will see its max pressure shortly after shutting down the engine.
  
  If everything is good, let the engine cool down completely and check coolant level in the tank. Adjust as necessary.

I'm gonna go for a drive.

Ken...

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Thanks for this very detailed list!!!

Totally agree on cleaning the engine block surfaces of any residue prior to installing the new parts. My thermostat keeps weeping coolant. Not bad but noticeable enough to create a coolant stalagmite! I tried using a scotch brite pad, but didn’t work all that great. I replaced it and it still leaks. Ugh.

I’m open to any suggestions.


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Quote:

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Originally Posted by JohnnyGraphic

Thanks for this very detailed list!!!

Totally agree on cleaning the engine block surfaces of any residue prior to installing the new parts. My thermostat keeps weeping coolant. Not bad but noticeable enough to create a coolant stalagmite! I tried using a scotch brite pad, but didn’t work all that great. I replaced it and it still leaks. Ugh.

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Is it possible that you overtightened the bolts? If so the mating surface may have warped. Proper torque is 89 in/lbs - about 7 or so ft/lbs.

Ken...

Quote:

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Originally Posted by kbcons

Is it possible that you overtightened the bolts? If so the mating surface may have warped. Proper torque is 89 in/lbs - about 7 or so ft/lbs.

Ken...

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Hmmm...Possibly. I know the 89 in/lbs is crazy low. It may not have felt tight enough, so I may have gone too tight.

Here’s a pic of a before and after of the block.
https://uploads.tapatalk-cdn.com/201...4a97df3e67.jpg

After cleaning with scotch brite pad.
https://uploads.tapatalk-cdn.com/201...c0dff286fe.jpg

I replaced it at that time with a brand new factory OEM thermostat.

Next time around, I’ll probably use some sort of RTV on it. I think 50’s Kid does it(?).


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Quote:

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Originally Posted by JohnnyGraphic

Hmmm...Possibly. I know the 89 in/lbs is crazy low. It may not have felt tight enough, so I may have gone too tight.

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Yeah it isn't much, but it's all you need. Except for the one that attaches the lifting eye, the bolts are small. All need to be 89 in/lbs. There are lots of the little guys on the engine so I invested in a cute little 1/4" drive torque wrench.

Quote:

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I replaced it at that time with a brand new factory OEM thermostat.

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Seeing that traditional gasket struck me as odd. The one I removed and the new one both have an embedded seal.[/quote]

Quote:

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Next time around, I’ll probably use some sort of RTV on it. I think 50’s Kid does it(?).

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Yes, he did use a really thin bead of RTV. I elected not to for a couple reasons: (1) BMW didn't so why should I if I'm using an OE part, and (2) cleaning up RTV at the next change would be a true PITA.

Ken...

Quote:

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Originally Posted by kbcons

Yeah it isn't much, but it's all you need. Except for the one that attaches the lifting eye, the bolts are small. All need to be 89 in/lbs. There are lots of the little guys on the engine so I invested in a cute little 1/4" drive torque wrench.



Seeing that traditional gasket struck me as odd. The one I removed and the new one both have an embedded seal.

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Yes, he did use a really thin bead of RTV. I elected not to for a couple reasons: (1) BMW didn't so why should if I'm using an OE part, and (2) cleaning up RTV at the next change would be a true PITA.

Ken...[/QUOTE]


Yeah, I’ve got 1/4” torque wrench I got from HF. I think I snugged it into place and it was already past the torque specs and it still felt really loose. Oh well. On to t-stat #3! At the right specs!

Thanks for the insight on the RTV. Rethinking my plan.

https://www.pelicanparts.com/BMW/tec...arge/pic01.jpg