L3901H Neutral Safety

SmokeyBear20252

New member

Equipment
Kubota L3901 HST 4WD
Aug 29, 2012
36
0
0
Hildebran, NC
Hello all,

My L3901H has been randomly failing to start. I can rock or sometimes sharply tap the HST pedal and it eventually finds a place that makes it happy and I'm off and running again. However, it's time to take care of the issue once and for all. I located the switch easy enough and was thinking about trying to adjust it before replacing it. I'm going to have to invest in a thin wrench to loosen the nut as the switch housing protrusion prevents me from accessing the nut with a regular wrench. It appears to be a 38mm but I wanted to be sure before buying a wrench. Is anyone familiar with the switch and what's needed to remove/adjust it?

Thanks!
 

angelo c

Member

Equipment
Couple a wheel barrows, shovels and beer
Dec 23, 2019
49
2
8
Neshanic NJ
Hello all,

My L3901H has been randomly failing to start. I can rock or sometimes sharply tap the HST pedal and it eventually finds a place that makes it happy and I'm off and running again. However, it's time to take care of the issue once and for all. I located the switch easy enough and was thinking about trying to adjust it before replacing it. I'm going to have to invest in a thin wrench to loosen the nut as the switch housing protrusion prevents me from accessing the nut with a regular wrench. It appears to be a 38mm but I wanted to be sure before buying a wrench. Is anyone familiar with the switch and what's needed to remove/adjust it?

Thanks!
Maybe measure it with a set of calipers ?
 

UpNorthMI

Well-known member
Lifetime Member

Equipment
L3200, L3901, MX5800, SVL75-2, KX040
May 12, 2020
850
566
93
Up North, MI
I just looked under my tractor. You are not going to need a thin wrench. There are two nuts on the switch you can get to the nut closest to the main switch body with a regular wrench, just loosen this nut and you will be able to move the other nut with difficult access with your fingers. If necessary hold the switch body as you loosen the nut that you can access. The nut size is in the 20MM range on my L3901 HST.

Good luck with this job.
 

SmokeyBear20252

New member

Equipment
Kubota L3901 HST 4WD
Aug 29, 2012
36
0
0
Hildebran, NC
Thank you!

I think we're looking at two different switches. The one on the bottom side of the tractor (brake switch) does indeed have nuts on both sides of the mounting flange and both are easily accessible. This is the Forward/Reverse pedal switch, located behind the metal shield behind the parking brake lever. To me, it looks like this nut should have been installed on the other side of the mounting flange (the actuator side) and it appears in that configuration in the illustrated parts diagram. Here's a photo of what I'm seeing. As you can see, the switch housing stick out further than the nut so I need a wrench thin enough to get in that small gap.




 
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SmokeyBear20252

New member

Equipment
Kubota L3901 HST 4WD
Aug 29, 2012
36
0
0
Hildebran, NC
UPDATE:

I managed to get the nut moved to the correct side of the flange as indicated on the illustrated parts diagram. The mounting flange is actually thread so once I managed to break it free, I was able to simply unthread the switch and nut at the same time. I've re-adjusted the actuator travel and so far, it seems to be working. Time will tell. And yes, those are pliers scars. LOL

 

SmokeyBear20252

New member

Equipment
Kubota L3901 HST 4WD
Aug 29, 2012
36
0
0
Hildebran, NC
Thanks, Chim. I'll read through that one as well.

By the way, here is the parts diagram showing correct position of the switch and nut on the flange.

 
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chim

Well-known member

Equipment
L4240HSTC with FEL, Ford 1210
Jan 19, 2013
1,781
864
113
Near Lancaster, PA, USA
There may be a difference between models. My L3200 had a locking nut on both sides of the bracket from the factory. I think the bracket itself was threaded too.

That adjustment was right after buying the L3200 new in 1012, so I could be wrong about the bracket being threaded. I do think I had to remove the bracket and spin it on the switch because the switch hit the heavier steel the bracket was bolted to.