markxengineering
Active member
The fan that came out (installed by previous owner) looks like it was the wrong one for at T1N, from a later model Sprinter. Price difference at SD Europarts is minimal between the two, but there are many design changes. Especially relevant are 1) Which flows more? and 2) Which turns on at a lower temperature? 3) Could the later model fan be considered an "upgrade" for T1N's?
Side by side:
I have forwarded this info to a friend who does nothing but design + test fans for his feedback, so will hold off on blade feature commentary until then.
The ring around the newer design fan makes it more of a PITA to undo the central fastening screw, but the increased spacing in between blades helps a little bit with access. Call it a wash. It took me a couple hours to do this job, which is reportedly possible in 15 minutes for someone with smaller hands and the right tools. I should have just moved the radiator.
Noticeable in the above photo is that the fan is not separate from the thermal clutch in the newer design, must replace both as an assembly. Fewer and fatter cooling fins on newer design = less efficient heat transfer, but cheaper to make. There is a through passage for airflow near the OD of the newer clutch which is blocked in the older one. This would cause more heat transfer. Maybe another wash?
From the other side, cooling fin design a lot cheaper and less efficient again for the newer part. Both have balancing pads in the clutch. I forgot to compare bearing sizes and try to see if fan was balanced separately from the clutch in each case. The blades do get bent a bit during handling and installation, but hopefully nothing that won't spring back. I wonder how much these parts creep with age and heat, my guess would be a lot, making fan balancing semi-pointless anyway.
Both fans themselves are made from 30% glass filled nylon, as are many plastic engine parts.
Comments welcome..
Side by side:
I have forwarded this info to a friend who does nothing but design + test fans for his feedback, so will hold off on blade feature commentary until then.
The ring around the newer design fan makes it more of a PITA to undo the central fastening screw, but the increased spacing in between blades helps a little bit with access. Call it a wash. It took me a couple hours to do this job, which is reportedly possible in 15 minutes for someone with smaller hands and the right tools. I should have just moved the radiator.
Noticeable in the above photo is that the fan is not separate from the thermal clutch in the newer design, must replace both as an assembly. Fewer and fatter cooling fins on newer design = less efficient heat transfer, but cheaper to make. There is a through passage for airflow near the OD of the newer clutch which is blocked in the older one. This would cause more heat transfer. Maybe another wash?
From the other side, cooling fin design a lot cheaper and less efficient again for the newer part. Both have balancing pads in the clutch. I forgot to compare bearing sizes and try to see if fan was balanced separately from the clutch in each case. The blades do get bent a bit during handling and installation, but hopefully nothing that won't spring back. I wonder how much these parts creep with age and heat, my guess would be a lot, making fan balancing semi-pointless anyway.
Both fans themselves are made from 30% glass filled nylon, as are many plastic engine parts.
Comments welcome..