Oliver 1755 transmission questions

I have noticed a couple of oddities during the first year of running this old machine.

One: There is a three-range lever on the right side of the console. It's similar to an IH "torque amplifier" in that you can shift between three different speeds on the fly without changing gears. Last fall, while running a haybine, I was in the lowest range; and the next time I pushed the lever forward, nothing changed. The lever seems to have come un-linked from the linkage. I only use the machine to move round bales to feed during the winter; so I've left the repair to warmer weather. If I open up the console and find the linkage intact, what would be my next moves? Is there an adjustment to take up slack? Have I neglected to put hydraulic fluid into a special compartment somewhere; and that's why the range lever is inoperable? If all of that fails, I guess that I would be left with a mechanical failure within the range mechanism itself.

Two: In extremely cold weather (-10F and below), the tractor starts well as long as I use the block heater and glow plugs. However, once idling, I put it in gear to move out of the shed to let it warm up without turning the shed into a smoke bomb. I seems that the hydraulic system has water in it, as the hydraulics and steering need some warm up time before they become operable. On the very coldest days, this seems to affect the transmission. Once I move the tractor out of the shed, I try to put the tractor in nuetral so that it can warm up. Problem is, the engine is loaded and the tractor tries to move when I let out on the clutch...even after I've shifted to nuetral. If I hold the clutch for a few minutes, I am then able to let out on it without killing the engine or the tractor trying to move.

Any insight?
 
Stand on the right side of the tractor. Look at the over under unit and then shift the lever . Does the linkage a round rod move on the over under unit. There is a dip stick for the over under unit. Have you ever checked the oil level? What are you using for hydraulic oil? It may be too thick for this cold weather. When you start the tractor make sure the transmission is in the transmissions low range. Do you have an operators manual? Start there. J.
 

OK. That's a beginning. Thanks.

How do I identify the over/under unit?

I'll check the type of hydraulic fluid that I'm using; but I'm assuming that it's a water issue, since the steering "freeze" can happen at almost any temperature below freezing. The transmission issues take really extreme temperatures. Both go away after a warm-up period.

I'm pretty sure that the old girl is due for some fluid and filter changes, once it gets warm enough to work on it without contracting frostbite.
 

And brake pads....and exhaust manifold...muffler...rebuild or replacement of the hydraulic pump (in hot weather the hydraulics go limp when it gets too hot...which old timers tell me to blame on the "spools" being loose)

It's a tough old beast; but definitely in need of TLC.
 
You asked: How do I identify the over/under unit?
It is located behind the engine. The dip stick is on the left side close to the linkage that works the clutch.
 
You better do a little checking before too much longer. You said : rebuild or replacement of the hydraulic pump (in hot weather the hydraulics go limp when it gets too hot...which old timers tell me to blame on the "spools" being loose). You need to trouble shoot the unit with a few gauges and not listen to these stories. How many of them know the correct way to trouble shoot the hydraulic system. But check it soon before you do more damage.
 
As far as the hydraulic pump goes, my father-in-law has run the machine for about four years now. He has, more or less, learned to make due with its quirks. The "spools" diagnosis is based on him describing symptoms to various people, not any kind of troubleshooting.

My fear is that "quirks" become, as you said, damage; so I'm trying to take care of issues one by one. Rolling balage by hand because the tractor is inoperable is quite a chore.
 
Checked the linkage for the over/under last night. The linkage is intact; but there is no "detente" to it. The lever acts as if there are no range positions. I wonder if this is due to a lack of fluid pressure in the transmission.

I also noticed a cylindrical can oil filter on the housing just above where the over/under linkage enters (and towards the rear of the tractor). I wonder if that filter is for the transmission?

What type of fluid is this transmission supposed to have?

Any hint as to the part number of that filter?
 

NAPA's search engine, given the make, model and year of the tractor came of with:

FIL 1307 for over/under transmission filter
FIL 1567 for hydraulic fluid filter

Sound correct?
 
Have no idea. There are 2 filters for the over under, but if you are going with the NAPA filter get 2 because the transmission uses the same one. Also use a good grade of tractor hydraulic fluid (Hy tran) instead of the type A.
 
Thanks.

Can you clarify some?

I'm trying to reason out what fluids are used where. Based on the dipsticks/filler locations and such that I know of, I'm assuming:

Obviously, there's engine oil. I have checked and filled that as needed. I use engine oil here. Heavy for summer, thinner for winter, no problem.

There is a resevoir of hydraulic fluid (which I check and fill with the dipstick just behind the seat) that runs the remotes and the steering. I use hydraulic fluid here. I also believe that this revervoir operates the hydraulic brake assist; because pushing the brakes can affect the operation of other hydraulics (bucket).

There is a filler location just above the pto (about waist high) that somebody capped off with half of a beer can held by a hose clamp (no lie...really). I assume that's for gear oil for the final drives to the axles and the pto and such. I haven't added anything here; but I assume it would be gear oil.

Then there is the transmission, which is a hydraulic shift and has this over/under unit. For this, I now see the dipstick near the clutch pedal. Is this the only reservoir of fluid for both the transmission and the over/under? Some references recommend automatic transmission fluid here. Is that correct?
 
You said: There is a filler location just above the pto (about waist high) that somebody capped off with half of a beer can held by a hose clamp (no lie...really). I assume that's for gear oil for the final drives to the axles and the pto and such. I haven't added anything here; but I assume it would be gear oil. I think the beer can is the cap for the cover for the PTO control valve. Is there linkage attached to it? If so that is not a fill or check plug. YOU NEED AN OPERATORS MANUAL!!
You also asked:Then there is the transmission, which is a hydraulic shift and has this over/under unit. For this, I now see the dipstick near the clutch pedal. Is this the only reservoir of fluid for both the transmission and the over/under? Some references recommend automatic transmission fluid here. Is that correct?
It is the dip stick and fill for the 3 speed over under .Automatic transmission fluid was the fluid of choice but has been superceeded by a good tractor hydraulic fluid like Hy-Tran The transmission is separate and also has its own filter which is mounted under the floor board. I will need to look tomorrow. I don't remember if the fill plug is the same as on a 50 series, It has been 37 years since I filled and checked one. It will take like 80-90 gear oil. Change the hydraulic filter as well. Make sure the micron rating of the filter is 10.
 
Great guess with the beer can. I looked at it again this morning before reading your reply and noticed the linkage to the pto lever. I assumed it was some kind of filler; because of the makeshift cover. Red herring.

Owner's manual. Yes, coming.

Still, though, the answers to my questions have been helpful because I'm trying to learn some of the "theory of operation" which will be helpful in troubleshooting. This tractor is beyond the point of just adding fluid and changing filters. It definitely needs that; but it needs repair.

Along with these transmission issues and fluid leaks. I have also been diagnosing the engine running weakly over the last two weeks. (See my 1755 fuel filter thread).

This thing is an adventure and an environmental disaster (as in, I can see rainbows on the pavement every time I step on the clutch) to say the least.
 
I have a 1974 1855 Diesel. Great old machine. You have
several points of fluid.
1. the engine dipstick is were you would expect on the left side
of the engine block. 15w/40.
2. Same side of engine and just past the engine dipstick is the
Over/Under Hydraulic Shif. Little cap on it with a dipstick
attached. Takes AF2 Auto Trans fluid typ A.
3. Hydraulic Unit on back of tractor. Has a large cap with
dipstick. On right hand side of tractor if standing behind unit.
Takes type 55 Hyd Oil.
4. Transmission and Final Drive. A little cap/filler plug under
and behind the seat at the top of the unit. Takes 80/90 Gear
Oil. Lots of it. 44 qrts of it. Maintain fluid level at bottom of the
TOP test plug hole located lower and next to the PTO shaft.

As to your cold moving 1755, my 1855 when started
sometimes does not want to steer or the 3 point hitch move up
or down. My levels are all up and unit seems that is is warmed
up. I found ( and this makes no sense to me) that if I shut off
the tractor. Let it set for just a few seconds and start it back up,
the steering works perfect and the 3point hitch moves just
perfect. I have never figured it out. I used to think it was due
to cold, but every time it happens, I just kill the engine for a
second or two and I mean just a couple of seconds, start it
back up and I have power steering and good Hydro"s all
around.
 
Yeah, for all my complaining about the issues with this machine. I never forget...the damn thing is 41 years old; and it still runs. As a matter of fact, it runs like a top now that the fuel and air filters are changed.

Thanks for all of the fluid fill tips. I just bought the shop manual; and what you say jives with that and is put a little more clearly.

Your hydraulics experience makes some sense to me. On very, very cold days (below -10F), the steering wheel is hard as a rock and no hydraulics until it has idled for a half hour or so.

On intermediate days, It will steer and have some hydraulics when I first turn it on; then they appear to freeze up. My solution was to let it idle longer, which works. However, I'm going to try your turn off/turn on trick to see if it helps in that situation.
 

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