NH TC33D Transmission Range Safety Switch Problem

   / NH TC33D Transmission Range Safety Switch Problem #1  

John_Mc

Elite Member
Joined
Aug 11, 2001
Messages
4,027
Location
Monkton, Vermont
Tractor
NH TC33D Modified with belly pan, limb risers & FOPS. Honda Pioneer 520 & antique Coot UTV
For some time, I could not start my tractor with the range selector in the neutral position between 1st and 2nd range, but the other neutral worked normally. Today, it stopped working all together. Fortunately, it waited to fail completely until after I got the tractor home from an afternoon of working in the woods on the far end of my property.

So it appears I need to adjust or replace the Transmission Range Safety Switch. The service manual suggests to "remove the left rear tire assembly for easier access to the switch." The tractor is on soft ground, so jacking it up to remove the tire may be a little tough, but I could probably manage it. The rear tires are filled, which makes dealing with them a bit of a chore.

Has anyone here adjusted or replaced the switch? Can it be done without removing the rear tire, or am I wasting my time and just need to bite the bullet and remove the wheel?

Things are supposed to warm up tomorrow, so I hope to get in to this before the rains come this weekend (or course, the tractor is parked right under the drip line of both the garage and the house roofs.
 
   / NH TC33D Transmission Range Safety Switch Problem #2  
I think they say remove the tire for a reason. Looking at the parts diagram #11 is held in place by 2 small screws and is tucked in close to the case amongst all the levers. I don't see any adjustment on the switch but the rod looks to have some.
 

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   / NH TC33D Transmission Range Safety Switch Problem
  • Thread Starter
#3  
I was afraid that was the case. I was hoping I could reach in and fiddle with things, but that may mot be possible.

The service manual does note that the switch can be adjusted up and down to obtain more travel by loosening the screws holding it. It also notes that the roller arm on the switch can get deformed, preventing the switch from operating properly. (or it could just be a failed switch - the tractor is 21 years old.)

I'm hoping it's just out of adjustment. They want $160 for the switch.
 
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   / NH TC33D Transmission Range Safety Switch Problem #4  
I would disconnect the wires from the switch and put a jumper in to get it back to your shop and then adjus/replace the switch.
 
   / NH TC33D Transmission Range Safety Switch Problem #5  
Have you tried to move the gear selector while your start switch is in crank position? If it needs adjustment, the wiggle/move trick will normally work. Yes, you should be able to see the switch without removing the wheel.
 
   / NH TC33D Transmission Range Safety Switch Problem #6  
As Diesel scout said - but if you cant access the switch figure out which two wires they are and jump across them will at least get it to a dry spot.
 
   / NH TC33D Transmission Range Safety Switch Problem
  • Thread Starter
#7  
Well, I found the problem.

I can see the switch, but could not quite reach it. I reached in with a screw driver, thinking I could depress the switch and start the tractor. I just barely touched the roller on the end of the switch arm and it fell right off, along with part of the arm. The roller is shown here sitting on the page from the service manual diagram.

IMG_3294.jpg


I've ordered a replacement from Messick's. Fortunately, they had one in stock.

I'm definitely going to have to remove the wheel to replace this.
 
   / NH TC33D Transmission Range Safety Switch Problem
  • Thread Starter
#8  
As Diesel scout said - but if you cant access the switch figure out which two wires they are and jump across them will at least get it to a dry spot.
Trying to figure that out. I'll never reach the connector on the switch. Trying to figure out where the wires run, so I could jump the other end.
 
   / NH TC33D Transmission Range Safety Switch Problem #9  
Good news is Messick's shows it still in stock so a local dealer may have one. Bad news is it is $160. But is still cheaper than a new tractor. :D
 
   / NH TC33D Transmission Range Safety Switch Problem
  • Thread Starter
#10  
Good news is Messick's shows it still in stock so a local dealer may have one. Bad news is it is $160. But is still cheaper than a new tractor. :D
Yes. Already ordered it.
 
 
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