Two gears at once?

[njensen]

Fellow tractor buffs:

I was bush hogging a field for a neighbor this last week, and has something bizarre happen on two different occasions. I think I am getting the transmission in two gears at once...

I have a jinma 184 (TY290 2 cyl motor). reached the end of a row, put the tractor in reverse, and began to let off the clutch... The tractor bogged down quickly and didn't move AT ALL. I suspect it would have died if I didn't get back on the clutch quickly. I pulled it back to neutral, and then back to reverse... no issues backing up this time... I wrote it off as a fluke and went back to mowing, only to have it happen an hour or so later.

Just as before, after moving from R->N->R, things were happy again... However, this time it bothered me and I started heading for home. I tore the lid off both the tranny and creeper box, and drained all the oil out of the gearboxes, (It needed a change anyway).

I certainly can't see anything in there that looks odd... I was expecting to find metal everywhere, but everything appears to be intact. Other than the tranny dipstick, (it has been ground on a bit -- I don't know how or if it was like that when I bought the tractor). The oil I drained surely didn't look *that* bad, (no metal that I could see, and not even all that dirty for its age). But I was amazed at the quantity; I overflowed my pan and made one heck of a mess in the garage.

One thing that I will mention is that it sure seems hard to shift things back and forth. I have actually broken the H/L shift lever in the past as well as sheared a roll pin on the 2WD / 4WD lever... For what it's worth, I really do try to baby the tractor -- I need it to last... But it has to do the work I bought it for too. Internally things seem to be doing what they are supposed to, (I can see the 4WD lever pushing the gear into the right place still and have no reason to think it isn't doing what it should). Has anyone else experienced 'hard' shifting?

I'm admittedly a transmission newby... But I know there has to be something that keeps the 2/3 fork that is disengaged in the neutral position while the 1/R fork is engaged, (and vice versa). But I certainly don't see it, and I don't have any manuals to dig through. At this point, I'm going to have a fresh look in the morning and see if I can't figure out what is holding the disengaged fork in the correct location. If I can't see anything immediately wrong, I'll refill the gear boxes and see what I end up with...

Thanks much all, I appreciate the knowledge you have
-Nate

 

[Affordable]

Not sure whats going on there,we have a parts book for your tractor that you can see a diagram of the transmission which might help. take a good look at both sides of the shift forks to make sure they are OK

Tommy
Affordable Tractor Sales
"Your Jinma Parts Superstore"
Home of compact Jinma, Foton, and Koyker Tractors and Parts, Wood Chippers, Backhoes - Affordable Tractor Sales Company

 

[greg_g]

It's hard to do anything with these Chinese tractors without the set of 4 manuals. Until you remedy that situation, perhaps this diagram will help. I've got more if you need them.

//greg//

 

[njensen]

Gentlemen,

Thanks much for the advice... I've actually bought all my parts from Tommy, Took me a second to realize this Tommy was the one I have dealt with. I'll get the manuals ordered right away.

Greg -- I see USN retired in your signature field. I was in the USAF for ~11 years. Was just about to pin on Maj and I decided to pull the plug, (I'm a computer engineer by trade, and I wasn't doing much engineering anymore). Last assignment was teaching at the AF Academy -- I was about done with that assignment, and I really struggled with the idea of going back to writing OPRs/EPRs all day. I actually have closer ties to the Navy now... We, (my current research lab), are partnered with a research group at NRL doing some great engineering work.

Anyway, back to the situation at hand... The picture is great -- that will be very helpful. Looking at that pic does confuse me slightly though... I don't see anything that prevents the 2/3 rod and fork from being actuated while the 1/R rod and fork are already engaged... What in the transmission makes sure that one rod/fork has been completely slid into neutral before the other is engaged? Is it only the shift plate pattern in the transmission lid? FWIW, the terrain was pretty steep where the issue occurred and I was shifting from 3rd to R, (In low range of course).

The way I have used the tractor in the past *rarely* has me shifting from 2/3 -> 1/R... I mostly use the machine for FEL work around my place, (lots of 1->R shifts... I also do a small bit of garden tilling, (all forward in L + creeper range).

Thanks again gents, your wisdom is appreciated
-Nate

 

[Turbo]

sound like your shifting pin maybe out of alignment/ bent, or worn. as you shift in to reverse it maybe hitting the 2/3 shifting fork, and pulling it back at the same time.

 

[greg_g]

What in the transmission makes sure that one rod/fork has been completely slid into neutral before the other is engaged? Is it only the shift plate pattern in the transmission lid?

Well yes and no. The shift plate works in conjunction with the detentes on the shift rods. Wear (slack) at either end of the shift rods, and/or wear on either end of the shift fork can lead to less than positive gear changes as well.

//greg//

 

[soulasphil]

Same thing happened on my Massey 35. It would get into 2nd and R at the same time. The cause was wear on the detentes letting the rods slip from their correct position and fall in the way of the lever. Never got around to repairing the gear box. Devised a way of unlocking it through the oil fill cap in a few minutes (only happened about once a month).

 

[njensen]

Fellas,

So I refilled the tranny gearboxes, (took just shy of 5 Gal). Put everything back together, and went for a test drive. I shifted things, (vigorously but within reason), and I never had the problem.

I finished up the neighbor's field without a hiccup... For what it's worth, it even feels a bit easier to shift now, (even though I have no empirical data to support that -- just my guess). Probably just wishful thinking on my part.

At this point, I think I'm just going to run it and watch it... I guess it was a good excuse to get some new oil in the tranny.

Thanks for the advice,
-Nate