speed on john deere b

[shanedog]

I got 39 b with a speed problem while pulling the sled. the tractor has 12.4-38 tires. The horn is suppose to be at 3 mph but I get to half thottle when the horn goes off. The manuel and tractor data both say 1st gear is 2.3 mph. So my question is it the tractor or the sled reading wrong? thanks

 

[JDJACK]

Get a hold of a gps and set to mph and see what it reads

 

[Anonymous-0]

Maybe your tractor was set up for 36 inch rear wheels. I'd follow jdjack's suggestion about the GPS, it would clarify things.

 

[Chances R]

About 15 years ago I was needing to figure out rpm vs mph for pulling. I ended up using a little math and a tape measure. I had a starting line and two finish lines. One was for 3 mph and the other 4 mph. Keep in mind that 3 miles a hour is exactly that, its 3 miles a hour. Figure out how far you will travel in say 10 seconds if going 3 mph. Have fun

 

[GoJDpuller]

Did this just happen once? Could possibly been in 2nd? I pull the same tractor and tires in first a lot you do have to be careful on how hard you bump the throttle

 

[shanedog]

This happens everytime no matter the class

 

[nl00sb]

ur prollu pushing 3 mph with 12.4-38 run about 1/2 speed till ur under load or half track then give her more

 

[MMZAck]

The 2.3 mph speed that is listed in manuals and at tractor data is for 48 inch steel wheels or 9.00-36 tires. Your ground speed at governed rpm of 1150 would be about 2.6 mph on 12.4-38 tires. If you bump the throttle much more it will easily go over 3mph.

Here are some questions:

How high does your engine turn at full rpm?

Did you have enough power to finish the hook?

Are you sure the range lever is set to L for 1st gear and not H for 3rd gear? (I wouldn"t think so because the range lever kicks itself to L when you shift in reverse to back up to the sled)

Does your range select lever say 1-3/2-4 instead of H/L? This would indicate a slow speed transmission but the range select shifts backwards to the regular H/L lever. Again, could have been running in 3rd gear.

Food for thought anyway.

Zack