E36 cooling system overhaul

[Spraggz]

Hello,I am wondering if you guys can help me out,I just purchased a 1999 323is with 184k and I am wondering if I should do a cooling system overhaul,the previous owner did it approximately 80k ago and if I need to what are the complete parts needed and where is a good source,I am in canada.thanks for your help.

[shogun]

moved to E36 forum

[Eric93se]

Well at the very least, get a new overflow tank and the o-ring seal for the bottom. New water pump and thermostat. New coolant (drain the block). Snug up the hoses clamps on the rest, don't over tighten.

It's up to you if you think the hoses look good and the condition of the radiator. Check the radiator for a production date, might be under the plastic cowl on the top of the rad.

[Bronickishere]

When I did mine, it was because the expansion tank literally blew off the hose attachment.

So I would definitely get a new expansion tank as that plastic ages over time under the hot engine bay so you don’t have that problem I had. That being said, guy above me is spot on with the rest.

I’d take it a step further though and get a lower temp thermostat so it runs a tad cooler as well as an aluminum racing radiator. If you don’t wanna break the bank, then disregard this. I always try to upgrade the stuff I’m replacing as racey parts tend to last a lot longer under normal conditions (depending on what they are).

Also definitely upgrade the water pump. The stock one is again, an aging plastic but the upgraded version is metal probably aluminum billet.

[Deus Ex Machina]

Hello,I am wondering if you guys can help me out,I just purchased a 1999 323is with 184k and I am wondering if I should do a cooling system overhaul,the previous owner did it approximately 80k ago and if I need to what are the complete parts needed and where is a good source,I am in canada.thanks for your help.

Look at Turner Motor Sport, a complete cooling system replacement kit including Radiator, expansion tank, pump, thermostat and hoses is very affordable and well worth it. Since cooling system issues are common I would want to start fresh with a verified "good to go".

[vaderTT76]

ECS also sells "complete kits".

[myblackcar]

Check RealOEM and do everything accessible from the front first (radiator hoses, radiator, expansion tank, thermostat, water pump).

While you are in there, check the smaller hoses that run into the block and heater core. These can take second priority assuming it is not leaking yet. It would be handy to have the hoses ready when you decide to do work under the intake manifold.

[JEC928]

There are so many hoses. Getting to the ones that myblackcar mentioned require pulling the intake manifold.

Real OEM is a great resource for their diagrams.

Here's the E36 323 radiator stuff:
http://www.realoem.com/bmw/enUS/part...BMW-323i&mg=17

and the whole system:
http://www.realoem.com/bmw/enUS/show...diagId=11_6077

plus the pump and thermostat:
http://www.realoem.com/bmw/enUS/show...diagId=11_6080

the intake manifold that gets pulled to access the bits underneath, a process that reveals a plethora of other plastic bits to replace:
http://www.realoem.com/bmw/enUS/show...diagId=11_6078

[jmo69]

ECS also sells "complete kits".

You'd be better off with FCP, ECS has gone down hill lately, no lifetime warranty either.

[Deus Ex Machina]

I'll be doing mine soon barring the radiator which has already been upgraded to aluminum. I think I am going to go with an aluminum expansion tank on top of the other components.

[RockinScott]

Consider a lower pressure radiator cap as well.

[Deus Ex Machina]

Good luck brother. I got an expansion tank leak today and dropped $600 on cooling system upgrade parts. Luckily mine already had the aluminum radiator upgrade.

[Eric93se]

Deus, I hope you caught the leak before it was able to overheat, the heads on these love to warp and crack!

Unfortunately when the needle hits the red it usually too late.

I plan to add a red LED to turn on when the overflow tanks low level sensor triggers. The OBC 'check fluid level' is not good enough and I've also disabled it in the OBC by setting it to Euro, did this to get rid of the low beam failure for HID's and LED tail lights errors.

[Deus Ex Machina]

Deus, I hope you caught the leak before it was able to overheat, the heads on these love to warp and crack!

Unfortunately when the needle hits the red it usually too late.

I plan to add a red LED to turn on when the overflow tanks low level sensor triggers. The OBC 'check fluid level' is not good enough and I've also disabled it in the OBC by setting it to Euro, did this to get rid of the low beam failure for HID's and LED tail lights errors.

The needle never moved, I never ran low on coolant. I have been driving it for very short distances and checking it on both ends. I think it's good. The red light is a really good idea.

[Bronickishere]

Good luck brother. I got an expansion tank leak today and dropped $600 on cooling system upgrade parts. Luckily mine already had the aluminum radiator upgrade.

Lol, lucky you because that’s one of the more pricey parts.

[Thrifty S50]

+1 for Coolant Res replacement First. I also had mine literally Blow up, in an In - n - Out Drive Through... I had replaced some Cooling parts a few years ago, but skipped the reservoir as i thought it was fine. Nope.

I actually just bought a bunch of Cooling Items for Black Friday. I went with the 88C Therm from ECS, they had the Best deal on OEM. I did FCP for a Meyle Metal Water Pump, and OEM plastic Therm-Housing and O-ring. Then also got the Mishi Rad and Electric Fan kit which DO come with a lifetime warranty, From Mishi tho