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Since my cooling fan self-destructed and took out the radiator, I need to fix/replace both. I will probably have the radiator recored at my local shop rather than replacing it with an E28 radiator, because it’s simple and repairable.

I am a little unclear on which M30 cooling fans are compatible with my engine. The engine is an M30B35 but with the old-style water pump and fan clutch in a red, 8-blade fan that I assume was the original B30 fan. The water pump was new two summers ago and the fan clutch is fine so I don’t want to unnecessarily replace those. Will the fan clutch I have work in any M30 cooling fan, or do I need to get a red E12/early E24 fan? I have checked the parts cross reference in the FAQ and it is not entirely clear to me. It seems to say that an E23/E24/E28 fan will work, but I’m not sure if it also means that it requires a new-style clutch and pump.

The fan blades are interchangeable with e23/24/28’s and are still available new from BMW although I believe the blades are now black. The clutch is unique to early and late water pump versions and the blades fit either version.

Early and late also use a different pulley, one's got a square bolt pattern, the other is kind of a diamond shape.

Thanks - I was coming to that conclusion on my own but it’s good to have confirmation. All the fans available a re 9-bKade black fans and the hub seems to accept either clutch. I called the radiator shop that fixed the pinhole leak in the radiator to get an idea what recoring it would cost and they said I could expect around 400-700 depending on size. Yikes!! There’s the price of brass for you. I’ll probably get a new E28 radiator in that case.

Theotherotter wrote: Wed Oct 29, 2025 8:11 pm ...and they said I could expect around 400-700 depending on size. Yikes!! There’s the price of brass for you. I’ll probably get a new E28 radiator in that case.

Zikes! Ebay and Amazon at time have had listings for aluminum ones regularly in recent years, I'd probably give one of them a try. Not as cheap as E28 radiators and a bit of a gamble on the unknown though. But easier install at least. https://www.ebay.com/itm/257182246713?_ ... R8SAgOHGZg

The one I linked to only appears to have one bung for the fan swtiches, but there are dual switches that fit, such as off an E30.

Thanks - I've seen the Chinese aluminum radiators on eBay and I'd kind of like to avoid them if I can.

As for fan switches, I have none. That's right, zero. That's the way the car has been for a long time.

Also going to replace the engine and transmission mounts when I fix this (I know they're worn). It's some insurance against the fan wandering into the radiator.