Farmall B still grinds gears.

I replaced the pilot bushing and throw out bearing, bushing fits input shaft good, replaced pressure plate and disc.
Adjusted clutch.
With tractor running, still grinds when installing into gear.
With clutch pedal pressed can see input shaft spinning very slowly, with pto engaged, it will not spin.
It has a slight drag on it somewhere.
Clutch is adjusted correctly, disc floats good.
Is there a coupler in the input shaft on these?
I don"t have a parts diagram of transmission or input shaft. Any more ideas?

Jack

"Is there a coupler in the input shaft on these?"

Yes.

If you go to cnh.com and drill down through the menus, you can view the partsbook on-line.

What oil did you put in the tranny?

I didn't change oil ain transmission, don't know whats in there.
We use this during the winter time.
Coldest it gets -35 below.

I can't find the parts menu.

The surest, easiest and quickest way I have found to get to IH parts catalog is to Google "Case IH parts catalog" and from there 2 clicks will bring up catalog.

The transmission is a sliding gear straight tooth spur gear type. It is fully on roller, or ball berings throughout. It can be driven into motion just by the air that is sandwiched between the clutch driven disk surfaces, and the PP/Flywheel. If the oil in the trans is 90 wt, (original) then changing to a multi wt gear oil that is thicker at higher temps (85-140) This oil will have a higher viscous drag, reducing the gear motion, but not eliminating it.
The trans will still make clashing noises when shifting, it has no syncros, and is designed to handle this issue.
The test is to start the engine with the trans in gear with the clutch down (test only). If the trans can be shifted through neutral to other gears easily and without any claching of gears (clutch still down) then it is very normal.
If the trans spins up when going to another gear with the clutch down, it is draging, and it is still not right.
Another method is to have a oldster that is familiar with operating Frmalls give it a drive.
Modest gear clasking is par for the course, it is the nature of the era. JimN

I have a 1939 B that does the same thing. If you hold the clutch down for a few seconds before you put into gear it will reduce the noise dramatically. Have also done the "test" with putting into gear before start tractor while holding down clutch. Very normal.

We have another B,it doesn't do this.
I am not talking about shifting while in motion.
You can hold the clutch in for a long time and still will grind when put into gear.
Will try test out later today.

I had the same shifting problem with my SA. In addition, I had some transmission noise which I'm sure most tractors of that era have. I drained the 90 wt and put in 5 quarts of Lucas Heavy Duty Oil Stabilizer. It now shifts much better and most of the transmission noise is gone. I don't know what the viscosity of the oil is so the thickness may cause hard shifting in the winter.

I'm gonna stick my neck out here a little bit.

If I'm reading you right, your input shaft will turn slowly and slightly after giving it time to stop after depressing the clutch pedal. It doesn't do so if you've got the PTO engaged. That suggests that the very little resistance of the PTO is enough to stop things for a "noiseless" shift (back to that in a minute).
Since you don't know what's in the tranny for oil now, I'd suggest draining and refilling it with 90 or 85-90 as a starting/reference point, and see how it acts. If it's still noisy and balky, try going lighter, like to 75. My neck's out because I'm suggesting that a lighter/thinner lube might be enough lighter than what's spun up by the input gears might settle down sooner (while in neutral) might not be heavy enough to turn the drive gears. I could be all washed up in that thinking, in that it could be that thinner oils can be thrown more easily in there, and do more to turn the drive gears, making the grind you hear.

Bottom line, I'd say fill it with 90 or 85-90 as a reference point. Use your judgment after the results from that, and move to thicker or thinner lube and see which way reduces the noise.

That said, and to echo JimN, it isn't going to go away entirely. These are closely-meshed but straight cut, flat-top gears. Even when your input shaft spins to a stop, It's very likely that you will NOT have a tooth lined directly up to a notch for it to slip right into gear. Which will require letting up on the clutch pedal a little to spin the input shaft enough to mesh the gears, which WILL create a grind. It's the nature of the beast.

Not sure why your other tractor doesn't act the same. Could be that it's been jammed into gear with the grinding enough and for so long over the years that the ends of the gears have a bevel that meshes more smoothly. But I'll bet that it's a difference in the viscosity of the lubricant.

jack check the coupling where the clutch shaft connects to the tranny. there is thin plate between the coupling. check it good. if it has the slightest wear in it, like being egg shaped or enlarged hloes, replace it.

also make sure the bolts are not worn.
those bolts are tapered.

i had the same problem with a 404.

if you have any questions please contact me.

good luck.

joe

I just split it there, and the rubber washers are worn and the bolts have some wear. Will check the plate.
I could hear soem scraping noise by the clutch
area when spinning the pto engine off.
I think that the coupler is the problem causing shaft to wobble.
hope that parts are avaible.

That stuff is like 300 weight oil.

A friend of mine recently had a similar problem with his B. The coupling plate on the drive shaft was installed wrong and pushing the shaft against the throwout causing it to drag on the flywheel.