Hydralic Oil Question

bluechip · Oct 13, 2004

The spur or straight cut gears in the Jinma transmission are noisy by their nature. Running the creeper in Low slows down all the gears in the transmission and reduces the noise. The "normal" H/L selector slows down the output shaft after it has gone through the gears so it is not going to change the gear noise situation. Early on we tried to "fix" this noise, changing gears, bearings and such to little avail. It does vary some from tractor to tractor, probably because of tolerance on the bearing bore or the gears themselves. This noise is usually present when creeper is in high, even in neutral. Heavier oil seems to help quiet it down a bunch but it does seem to be more of a design issue than a defect issue.

Greg, sounds like maybe you had a throw out bearing issue on yours if a clutch change helped, that or they put in heavier oil while they had it...

greg_g · Oct 13, 2004

( Greg, sounds like maybe you had a throw out bearing issue on yours if a clutch change helped, that or they put in heavier oil while they had it... )

I agree Chip. That was my diagnosis from Day One, but the dealer refused to take action. The exact response I got was, "it's under warranty, bring it back if it breaks".

I replaced the Asian fluids on Day Two, the noise persisted. The clutch went out at 50 hours, and the dealer cheaped out by simply replacing the disc. the noise persisted. It was during this period that I experimented with gear oil viscosity. Even with 140W, the noise persisted. When the clutch went out again at 100 hours, I demanded a whole new clutch pack. The noise went away.

My point to Richard was; if the noise is bad enough to force him into Creeper/Low for everyday use, then it might be time to start looking for WHY.

//greg//

JohnS · Oct 13, 2004

Greg,
Given the hours Richard has on his machine, if it was the same issue, it "should" have raised its ugly head by now. He probably just has the "normal" Jinma gear whine. I used to run in creeper-low, to reduce the whine, as well. Now, I just block it from my mind. If it was a clutch/throw-out bearing, I would expect I'd have it let loose within the first 100hrs. Its next to imposible to quantify "normal" whine from excessive. Even if I listened to someone elses tractor, all I could say is "yes, that sounds similar to mine, shouldn't be an issue". If you hit 50hrs, without a breakdown, you are probably experiencing "normal" whine. If someone has a new tractor and is not sure, can't hurt to register the issue with the dealer, just in case there is another problem going on.

greg_g · Oct 13, 2004

I wasn't suggesting it was his clutch John. It's only logical to assume it would have gone out much earlier, as mine did. I just used it as an example of "something" that can cause a transmission noise over and above the subjective "normal level". Plus, I am a hearing aid wearer - which makes my sense of hearing even more subjective - AND I had the opportunity to own a previous JM254 that DIDN'T make the same noise.

Richard on the other hand, may have much better hearing than do I. But I don't think he's had the opportunity to compare it to another Nortrac. Nor does it sound like he's placed any continuing stress on the (normal) Creeper/HIGH tranny/LOW gear train during those 300 hours.

If it were mine, I'd STILL want a more definitive idea of whether that's a "normal" whine - or something that bears further investigation. Especially since the engine is working with a 5.4 to 1 gear reduction when the Creeper gear engaged. But if Richard's happy paying for the extra fuel consumed, so be it.

//greg//

ToolManRick · Oct 13, 2004

( If it were mine, I'd STILL want a more definitive idea of whether that's a "normal" whine)

Oooo, This sounds interesting. I have an old decibal meter. Bet I could pull the breather plug and rig a tube that would fit the end of the meter (thus eliminate engine noise to some extent) and take readings of all my gear ratios. Would even be interesting for me to see the difference. Anybody other than me interested? I might just do it for fun.

JohnS · Oct 13, 2004

Yes, very subjective, and everyone has different experiences. Both of the Jinma's I've owned, had similar whine. It also increased, going from 1st, to 2nd, to 3rd gears (in low range, don't know about high range). In 1st gear, it was hardly noticable (again subjective). Using creeper/high range reduced the whine significantly. Filling the tranny, to a higher level than dipstick mark (recommended by M. Stuart), lowered the noise slightly. Also, as you mentioned, gear oil helps, and age/run-in reduces the noise. Input that I have from others, would indicate that your experience with no gear whine, on your first tractor, is not the majority, and it is probably the minority. Maybe, once in a great while, all the particular clearances, etc, are absolutly perfect. Could only speculate, why there would be no whine.

RICHARDG · Oct 13, 2004

Well,,it has over 300 hrs,and its whined like we are talking about since day one,[when you run creeper high,mid shifter low,,never really run it high high],,,so Its a good bet its just the trans./gears/set up,making it whine,especially since others have said the same thing,it also sounds like that,not clutch,sound sounds like it is coming from basicly under seat area. And going from 30 weight to 40 weight didn't seem to make any difference in that sound..... It just seems happier running the gears I run in,,when something sounds bad or odd,and you can make it sound good or normal,,seems to me thats the way to do it,,but I don't know,,,have thought about whether you could do any damage to something running it the way I do,,but it appears not,,any body got a thought on that? You wouldn't think so,,but I ain't much of a mechanic,or several other things for that matter...thingy

SPIKER · Oct 13, 2004

hi richard:

I run mine ins HH1~2 all the time when diong flat level work, I use LH1~2~3 for slow steady and pulling work. I hardly ever use the HL combo as it makes LOTS of gear noise as the creeper gear in Low has the gears spinning faster on the primary side. anyhow the primary range selector is the front one, the creeper selector is under the seat. the gear shifter is dead center for R, 1, 2, 3, and yes I have only once or twice used the HH3 and that was for road travel back from neibors and for break in only... /forums/images/graemlins/smile.gif not sure of the speeds but don't worry much about that anyhow...

MarkM /forums/images/graemlins/smile.gif

greg_g · Oct 13, 2004

( the primary range selector is the front one, the creeper selector is under the seat. the gear shifter is dead center for R, 1, 2, 3 )

I think you're going to get a few arguments about this Mark, so I've attached the diagram from the Jinma operator's manual. Under Controls and Instruments it identifies #8 as the creeper shifting lever , #9 as the main gear shifting lever , and #10 as the auxiliary gear shifting lever . The translation is pretty clear about the forward lever being for the creeper gear. My own translation of #10 is High/Low Range Selector Lever

//greg//

SPIKER · Oct 13, 2004

greg that could be:

I use the front one as the primary shifter for H & L and the back one under the seat as the creeper gear. as it seems to make way too much noise if it is in L. my manual is 1999 but I didn't actually check to see if it says that the one under the seat is the creeper lever.

Markm