6 vs 8 vs 9 blades cooling fan?

[GGR]

Without reaching alarming levels, my engine temperature has a tendency to rise while I’m stuck in traffic on hot days. I’m going to replace the thermostat by one that opens at a lower temperature. But I’m also considering replacing my current original 280SL 6 blades fan by an 8 or 9 blades fan. It seems that some 250SLs came with an 8 blades fan, p/n 1082050406. According to EPC that fan never equipped the 280SL, I wonder why. I also see on the net a 9 blades plastic fan, p/n 1102000323 that is supposed to fit quite a number of MBs, including the 250SL as a replacement, but not the 280SL.

I’m tempted by the plastic 9 blades one, however, I’m wondering why it is not referenced as a replacement for the 280SL also? I’m particularly concerned by the overall diameter. Would anyone know if the 8 blades 250SL fan has a bigger overall diameter compared to the 280SL 6 blades one? Did anyone ever try that plastic 9 blades on a 280SL? If so, does it clear the shroud? I read that MB is now supplying a plastic fan as a replacement for the 280SL. Is it this 9 blades 1102000323 one?     

For the ones who have followed my build thread they know my car is not stock. However the 280SL 6 blades fan does clear my set-up, leaving very little clearance with my top radiator hose, hence my concern about overall diameter.

Thanks for the help!

[GGR]

This is the 9 blades fan I'm considering: http://www.ebay.com/itm/Mercedes-1965-1985-Fan-Blade-Plastic-NEW-1-year-Warranty-/271250486696?pt=Motors_Car_Truck_Parts_Accessories&hash=item3f27c9f5a8&vxp=mtr

[WRe]

Hi,
280SL US models with A/C had an 8 blade fan (A1082050206); see www.sls-hh-shop.de/en/230-280SL-W113/50-Cooling-System/50-c-Cooling-System-280SL/. See also here www.everythingbenz.com/z/part/1082050206-mercedes-engine-fan-blade for a M116 V8 motor (?).
...WRe

[GGR]

Hi,
280SL US models with A/C had an 8 blade fan (A1082050206); see www.sls-hh-shop.de/en/230-280SL-W113/50-Cooling-System/50-c-Cooling-System-280SL/. See also here www.everythingbenz.com/z/part/1082050206-mercedes-engine-fan-blade for a M116 V8 motor (?).
...WRe

Thanks! That's quite useful! Now that you're pointing it out, I should go and check in my "cooling stuff" box, I'm sure I have a fan out of an M116 3.5 in there. If I find it I will give it a try.

Interestingly, the 9 blades plastic one Autohaus is listing as a replacement is the one I mentioned before. I wonder if plastic blades help reducing the "propeller" noise at higher rpm?

[dowsup]

Based on what I have read in "Original Mercedes SL" by Laurence Meredith, the 250 SL came equipped with the 8 blade fan.  My problem is not having a shroud due to the overheating with the automatic trans.  So, I am going to replace the fan first and try to find the shroud.
BBW

[GGR]

The w113 fan shroud is hard to come by. But the w108 4.5 one looks to be close enough to work on the Pagoda with minor modifications. It may be a temporary fix until you find the correct one and may save you a head gasket.

[alchemist]

The shroud makes a big difference in cooling. So, your problem may not be how many blades you have, rather than missing shroud and faulty clutch between the fan and the water pump. Have you performed the newspaper test to see if the clutch is engaging when the engine is hot? I hope this helps.