Trans problem

[Bigernie]

Ford 8n transmission runs like tractor in 4 th gear when in neutral.
Can shift into any gear including 4th and it kills the tractor. Took of
shifter plate and everything looks lined up. It?s not stuck in between
any gears or stuck in 4 th is there anything else I can Check or what
can could this problem thanks Ernie

 

[deanostoybox]

There is a bearing between the input shaft and the output shaft. Perhaps that is seized.

 

[soaked]

Here is a pic of trans in 4th gear. The socket extension shows the connected coupling.
You drained your fluid and verified the couplings positions? ( respectfully)

Could it be in reverese not 4th?

If reverse gears rusted together---

John

 

[shaun wallace]

The gear to the left of extension and to rite of one with teeth knocked off seizes to counter shaft. Will drive forward with trans in neutral

 

[Bigernie]

Did drain the oil so I could see the coupling that goes from 2 nd and 4th . I can see it moving back and forth when moving the shift plate from 4 th and 2 nd but it?s hard to see it under the reverse plate. 1st and 3rd coupling are easy to see. it?s definitely a high forward gear because the tractor will move forward but it?s like your starting out in 4 th gear and has no power thanks for the picture

 

[soaked]

4th gear takes alot of clutch feathering, and noticably more then 3rd or 2nd.
So if you think it's in 4th, then it probebly is. If not by the coupling, then by seizing. The 4th gear on the countershaft should spin freely in neutral. Not sure if possible to turn engaged pto shaft, by hand, with clutch down, and see if it is.

Your description sounds like two gears engaged at once.

If not by couplings, then from seizing.

Wonder if it has all the right parts, and assembled properly?

Can take more pics if you want.


John

 

[Bigernie]

In neutral and couplings in between gears where they should be what gears should should spin freely on there shafts? Thanks

 

[soaked]

Spinning free wasnt a good description.

Was trying to describe an un - cogged,
Gear, and way to test. I'm not coming up with a way to determine a driven, from a drive pair of gears. (They don't spin freely.)

The remedy for being in two gears at the same time is to wrench the engine backwards, until the binding goes away.
You haven't had to do that.


Do you have the FO-4 shop manual?

John

 

[Bigernie]

Yes I do have a manual

 

[soaked]

So if Deano has it right, and the input shaft is " welded" to the main shaft, from bearing issue, then neutral would be main shaft turning at engine rpm? So a speed faster than 4th?
And selecting a gear causes the bind, and kills the engine?

John

 

[Bigernie]

That describes the problem pretty well. I?m looking at main shaft components, fig. Fo108 in the manual what bearing would be seized to the shaft? Thanks

 

[soaked]

The pilot bearing, part 30.( 9n7120), is what I thought Deano was referencing.

John

 

[deanostoybox]

Yes, 9N7120

 

[Bigernie]

So if the bearing is seized is there anything to try and unseize it or is it shot and I have to split tractor and replace thanks

 

[deanostoybox]

"So if the bearing is seized is there anything to try and unseize it or is it shot and I have to split tractor and replace"

IF it is that bearing, and IF you could get it freed up, it is likely it is compromised and will fail again or cause damage elsewhere. The same IF it should be one of the gears. The best course of action would be to do a complete disassembly and inspection of all parts in the transmission. That would require a "double split".

You can tell if it is the bearing by jacking up one rear wheel off of the ground, having all shifter forks in neutral position, and the clutch pedal fully depressed. Turn the rear wheel while watching the two front gears which have the bearing between them. If both gears turn together it is the bearing. If there is a difference in speed between the gears it is one of the gears that is stuck.

 

[Bigernie]

Thanks for the tip on jacking the tractor and spinning one wheel. Both gears spin the same speed so it looks like the bearing is seized . Is there anything I should be aware off when splitting tractor and pulling everything apart thanks

 

[deanostoybox]

"Is there anything I should be aware off when splitting tractor and pulling everything apart"

Sorry, but I can't help with that. When I go in for a clutch I just pull the engine.

 

[Bigernie]

Thanks for all the imput