Pre-1987 Cooling system Update

[Jnungesser]

Hey, so I made a post a little while ago. I cannot find pre-1987 radiators for my 325es. I’m going to retrofit it with the updated cooling system. But I need a reference or possibly a guide to know what parts I need to make it work. Should I go with the updated components or is there something I need to know prior to starting it? I don’t know if there are significant differences with the engine I would need to keep in mind before I start throwing parts on the car.

Any suggestions or possibly pictures of the engine bay and cooling system would be nice too :)

thanks guys!

[Reichart12]

Compare part diagrams on RealOEM for the different models. If you go to a newer late model radiator, the overflow tank, hoses, and water pump will also need to be changed.

I changed my 325e to the m42 radiator with integrated reservoir and late model water pump. Had to cut one hose for fitment but it's nothing too complex.

[dvallis]

Here's the E30 coolant system. You can substitute any radiator you like by connecting it to the top and right ports of the thermostat. For example, we converted to a 2" thick double pass radiator with inlet and outlet on the right.

Auto Zone is great for hoses. Measure what you need then ask the manager if you can browse their behind the counter hose stock. I stood there for an hour and found exactly the right hoses.

[Northern]

I think it has to be less effort to find a radiator that fits than replace everything.

To convert, you'd need a list like:
Radiator
Rad hoses
spider hose (for reservoir)
reservoir +bracket and add a stud.
Water pump
Rad top bracket.

Not sure if the tstat housing is different (coolant temp sensor holes aside), I think it is, but I didn't notice a difference.

I'm probably forgetting some stuff too.

[e30sh]

Don't forget the timing belt cover on the late model has the threaded boss for the crossover tube mount.

[Northern]

^ I forgot about that, and the crossover tube entirely