Ford 871 Question

[KCTractors]

A Ford 871 with the Select-O-Speed transmission. I bought the tractor dead. Got it running good and used it brush hogging for 2-3 hours. Transmission worked fine. Was parked about two months, now all the speeds seems to work but when put in 9th, transmission will shift into the gear momentarily and then the tractor will come a stop. Put transmission in 8th or 10th and the tractor will take off again. Any ideas what is going on.

 

[KCTractors]

A Ford 871 with the Select-O-Speed transmission. I bought the tractor dead. Got it running good and used it brush hogging for 2-3 hours. Transmission worked fine. Was parked about two months, now all the speeds seems to work but when put in 9th, transmission will shift into the gear momentarily and then the tractor will come a stop. Put transmission in 8th or 10th and the tractor will take off again. Any ideas what is going on.

Nobody has any ideas, That surprizes me,

 

[Sean in PA]

There is no single part in the S-O-S transmission that only affects a single speed when there is something wrong with the part. The Service manual has a table of the various components involved in controlling each speed, and most parts affect 3 different gears, so having a problem in a single gear is unusual. Are you sure that all the other gears work fine?

 

[KCTractors]

There is no single part in the S-O-S transmission that only affects a single speed when there is something wrong with the part. The Service manual has a table of the various components involved in controlling each speed, and most parts affect 3 different gears, so having a problem in a single gear is unusual. Are you sure that all the other gears work fine?

I run the tractor today when in 3rd gear it sounded like it pulled rpm's down for few seconds ( 5-10-) and went back up to the normal rpm's and now every range seems to be working.

 

[Sean in PA]

I run the tractor today when in 3rd gear it sounded like it pulled rpm's down for few seconds ( 5-10-) and went back up to the normal rpm's and now every range seems to be working.

Even 9th?

 

[KCTractors]

Even 9th?

Yes even 9th.

 

[Sean in PA]

Sounds like there might have been something in the fluid that was temporarily blocking an internal passage. I would change the fluid and clean the screen just to be safe.

 

[Tony Jacobs]

Nobody has any ideas, That surprizes me,

1) what’s the serial number of the tractor ? 2) what’s the casting number on the transmission ? Overrunning clutch or Direct Drive clutch ? 3) What type of oil is in the transmission ? When was it last changed ? 4) When was the last time the Shifter and short cable , the pto cable , and the bands were adjusted ? 5) When was the trans filter changed last ? 6) When was the last time pressure was checked ? 7) How many hours are on the tractor ? How much wear is on the inching pedal ? Completely smooth or grid/traction pattern still on it ? 8) How many threads showing on each one of the band adjustment screws ? We are suppose to guess with zero information ? On an overrunning clutch 312259 transmission 9th and reverse usually act up first but it can also be varnished up from using the transmission oil . Valvoline 813 10w30 hydraulic oil is THE ONLY OIL to meet the M2C41 Original Ford Spec for the SOS . None of the 134 A,B,C,or D oils even come close never mind garbage no name oil like tractor supply crap . There is some Texas Refinery Corp and Mystic brand oils that exceed the spec but I’m betting you wouldn’t want to spend the money on it until you decide what you’re doing with it .

 

[KCTractors]

1) what’s the serial number of the tractor ? 2) what’s the casting number on the transmission ? Overrunning clutch or Direct Drive clutch ? 3) What type of oil is in the transmission ? When was it last changed ? 4) When was the last time the Shifter and short cable , the pto cable , and the bands were adjusted ? 5) When was the trans filter changed last ? 6) When was the last time pressure was checked ? 7) How many hours are on the tractor ? How much wear is on the inching pedal ? Completely smooth or grid/traction pattern still on it ? 8) How many threads showing on each one of the band adjustment screws ? We are suppose to guess with zero information ? On an overrunning clutch 312259 transmission 9th and reverse usually act up first but it can also be varnished up from using the transmission oil . Valvoline 813 10w30 hydraulic oil is THE ONLY OIL to meet the M2C41 Original Ford Spec for the SOS . None of the 134 A,B,C,or D oils even come close never mind garbage no name oil like tractor supply crap . There is some Texas Refinery Corp and Mystic brand oils that exceed the spec but I’m betting you wouldn’t want to spend the money on it until you decide what you’re doing with it .

The transmission is a 312259. On the adjusters there is about 1/2" to 3/8" showing yet. I bought the tractor with a bad diesel engine. Guy said that the transmission was worked on by a New Holland Dealer shorty before the engine went south. There is a little thread showing on the inching pedal. Would this be a later transmission. I can not read the serial number on top of transmission because the battery acid got to it.

 

[Tony Jacobs]

The transmission is a 312259. On the adjusters there is about 1/2" to 3/8" showing yet. I bought the tractor with a bad diesel engine. Guy said that the transmission was worked on by a New Holland Dealer shorty before the engine went south. There is a little thread showing on the inching pedal. Would this be a later transmission. I can not read the serial number on top of transmission because the battery acid got to it.

312259 is the early overrunning clutch type transmission . Battery acid on diesel serial numbers is a common problem . What does 1/2 to 3/8 mean ? I asked how many threads are left showing on the band adjustments ? A brand new transmission with brand new bands will show 5 threads , average wear after 60 years of proper uses and care will show 3 1/2 threads , if it has been used hard or neglected like adjusting bands too tight , which happens the screwdriver slot can be right down to the nut . The grid pattern or traction pattern on the inching pedal can be worn partially off maybe 50% with normal use by 2000/3000 hours . If the user worked is wet sticky soil it would act like sandpaper and the pedal could be completely smooth at 2000 hours so it’s just something I look at . It’s not as accurate as the thread count is . How much of the spline on the input shaft was worn off ? Did you look at it when you had the engine out ? Diesel’s are worse than Gas because or the harmonic vibrations from the firing pulses of the Diesels kind of makes the disc chatter back forth on the spline wearing more than the gas engine . With the lower compression gas engine firing pulse is less violent in the cylinder which means it is less at the flywheel . Did ever service the transmission ? Band adjustments , shifter and pto cable adjustments , check and or replace the oil filter , use the proper Valvoline 813 oil ? Anything else is junk .

 

[KCTractors]

312259 is the early overrunning clutch type transmission . Battery acid on diesel serial numbers is a common problem . What does 1/2 to 3/8 mean ? I asked how many threads are left showing on the band adjustments ? A brand new transmission with brand new bands will show 5 threads , average wear after 60 years of proper uses and care will show 3 1/2 threads , if it has been used hard or neglected like adjusting bands too tight , which happens the screwdriver slot can be right down to the nut . The grid pattern or traction pattern on the inching pedal can be worn partially off maybe 50% with normal use by 2000/3000 hours . If the user worked is wet sticky soil it would act like sandpaper and the pedal could be completely smooth at 2000 hours so it’s just something I look at . It’s not as accurate as the thread count is . How much of the spline on the input shaft was worn off ? Did you look at it when you had the engine out ? Diesel’s are worse than Gas because or the harmonic vibrations from the firing pulses of the Diesels kind of makes the disc chatter back forth on the spline wearing more than the gas engine . With the lower compression gas engine firing pulse is less violent in the cylinder which means it is less at the flywheel . Did ever service the transmission ? Band adjustments , shifter and pto cable adjustments , check and or replace the oil filter , use the proper Valvoline 813 oil ? Anything else is junk .

Didn't do anything with the transmission beside changed the oil. The band adjusting nuts had about band #1 about 3.5 threads, #2 about .5, and #3 about 2.5 threads. The picture shows #2 and the inching pedal and the input shaft.