Fan installed backward

zd28er

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Zd28
Aug 29, 2025
6
10
3
Tennessee
Hello, first post here.

I've had a zd28 mower, used, for about 4 years. Has always tended to run a little hot. Today I noticed that the fan appears to be cupped the wrong way. I think someone installed it backward when they rebuilt the engine. Has anyone else experienced this? I assume I'll need to remove the radiator to get to it.
 

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JasonW

Well-known member
Jan 29, 2015
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Al
No experience with this mower but which direction does the fan rotate? If it is backwards you should be able to get to it by removing the fan shroud.
 

zd28er

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Equipment
Zd28
Aug 29, 2025
6
10
3
Tennessee
Standing behind the mower looking forward, the fan rotates counter-clockwise. Seems the concavity is wrong. It should thinly bite into the air and then curve the air back towards the engine.
 
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Old Machinist

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Kubota LX3310 cab, JD 4310, NH 575E cab backhoe, JD F725, Swisher 60", etc.
May 27, 2024
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If it rotates counterclockwise it is indeed mounted reversed.
 

nbryan

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B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Jan 3, 2019
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If the radiator fan pictured is supposed to pull air through the rad towards the engine then ya, the cupping of the fan blades should be facing the direction that air is being moved, not away from.

If flipped your fan will become way more efficient and move way more air.

I assume the fan as pictured from behind rotates counter-clockwise when engine running?

I would also look up the online parts catalogue as those diagrams are orientation-true.

Here's my B2650HSD fan for a reference:
 

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BBFarmer

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L3560HSTC-LE LA555 FDR1672 BB1272 SoldL3301HST
Jul 12, 2024
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Terry, MS
That is a sho nuff backwards mounted fan....... if i've ever seen one.
 

mendonsy

Active member

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B7500HST/LA302
May 28, 2012
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Mendon, NY
The problem is ..... reversing the fan itself will not change the direction of the air flow. You would need to reverse the rotation or get a fan with the blades reversed.
 

zd28er

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Zd28
Aug 29, 2025
6
10
3
Tennessee
I'm okay with the direction of the airflow...front to back, sucking air through the radiator. The problem is that, as/is, it is pushing the air mostly sideways and not pulling as much through as it could if reversed.
 
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NorthwoodsLife

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Kubota B7100(sold), Kubota LX2610 Cab
Oct 15, 2021
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Nite and day... blades spinning the same direction... It's all about pitch.

 
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GeoHorn

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May 18, 2018
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Be aware that SOME mowers are actually designed to BLOW air thru the radiator ..rather than Suck it… in order to reduce radiator-clogging from grass cuttings and such.

(Historically, some ag tractors do / did the same thing and the reverse-flow was purposeful.)
 
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