Cooling System Ovehaul Question

[Charlemango]

Hey everyone, been lurking these forums for a looong time but finally got an E36 M3 a few weeks ago, so I figured its time to join. I have a cooling overhaul question. There is tons of info about mileage intervals, how to do it, parts etc... But my question is this: my car has 93,xxx miles. It came with records for an overhaul in 2010, 12 years ago now. The mechanic who did the PPI didnt see anything, but it sounds like visual inspection isn't good for much on these. So what does the forum think? I definitely will do it before 130k, but is it advisable to do now just on account of age?

Thanks!

Edit: the car had ~70k when the work was done last, so its been driven about 20k in the last 12 years.

[scoobiedoo2029]

i see your saying m3/4/5 not a 318....the expansion tank is basically a total POS. the radiator is just cheap insurance. and i dont remember when the change over from the plastic waterpump was, but its worth inspecting. the stock parts are just a few hundred bucks and an afternoon of time to avoid the possibility of towing,

the condition of your installed parts is very dependent on storage conditions, i personally wouldn't trust the expansion tank and the radiator. and while your in there you might as well do a waterpump and thermostat and thermostat housing. a tow truck can cause some interesting issues nowadays when last i looked the front control arms are no longer available and the rear lower control arms are made of tin foil and the camber bolts that are in there factory like to seize.

[Eric93se]

I concur with Scoobie. Expansion tank is a must. And as mentioned you can get all the parts (everything) for around 300. Rein and Behr are good brands, Rockauto has most if not all parts. I upgraded to an all alum rad, but the fan shroud needed trimming. I actually had a rough section of fan shroud rub a leak in the rad, it must have taken a few years for that to happen but just pointing that out.

When you have an empty cooling system do not fill to the cold line, fill to the very top of the expansion tank, that needs to be done to push air out. The screw should also needs to be fully removed. Then remove the excess coolant with a $2 turkey bastor.

[Eaglesail]

Do yourself a favor, consider replacing the entire cooling system including water pump, thermostat, expansion tank, all hoses, including also radiator. In doing so, also replace all belts and tensioners...Also check the health of the alternator although they don't go bad as often, but an (while you got things apart effort) also is opportunity to replace the oil filter housing gasket, a usual with 2.5 . They go bad often after 100k! leak oil badly! Make it all good for the next 100k! It is not expensive to do if you do the work yourself.