I borrowed a friends 1970's Jr. 300b and now the hydraulics have quit on it. Here is all that has happened so far. I unloaded it from my trailer and noticed it was leaking from the o-ring around the transmission filter (vertical filter). Got a new filter and o-ring and after a couple tries found out the last o-ring was put on wrong. The o-ring has to be put into the housing first then bolt the cover on. This took about 3 weeks between when I noticed the leak and got back down there to fix it When I parked it all hydraulic were working. After changing the filter I added hydraulic oil and now I have very little hydraulic function. The only thing I can get to work are the stabilizers and they move slow. If I stand on them it won't raise me up. The main boom will move a little but mostly just moving the slack in the pins. No movement at all in the bucket. It went into reverse once but I quickly put it back in neutral because both buckets were down and now it won't go forward or reverse. I took the line off the stabilizer and hit the lever. It shot out about six feet and within 10 seconds it was down to a dribble out the hose. Last weekend I was back down and crawled under it for another look and saw the short black hose going from the transmission to the hydraulic filter was mostly collapsed and covered and leaking hydraulic oil. On the JD website it says this is a 1" X 3-3/8" hose. Is this the suction line for the pump and could this be causing my problems. JD didn't have any hose, is 1" air hose fine to use here? Also where is the transmission dip stick on this backhoe. Sorry for the long post just trying to provide all I can. My friend thinks the hydraulic pump died suddenly and wants to send his mechanic to check it, I'm just trying to check the simple stuff first. Thanks for the help
I don't know the layout of this machine, but most likely the pump is not the problem. That hose is a good place to start, I'd take the old hose to a hydraulic shop and see what they recommend. It's probably not supposed to be under suction. You'll probably have to drain the fluid to replace that hose, check and clean the suction screen and the hydraulic filter while you're at it. What did the old transmission filter look like? lantraxco might be along with better info...
That hose is a return from the filter for excess charge oil. Air hose is not fine, you need something that is rated for oil service and heat. Kind of hard to follow, but are you saying the transmission is also affected, no forward or reverse? The hydraulic pump gets it's oil from the tranny pump, so if the transmission won't drive, first thing you need to check is the clutch pedal, halfway down should put the reverser in neutral, all the way down and the mechanical clutch behind the flywheel disconnects for ease of starting and everything stops turning, including of course the transmission pump.
Hi Delmer, LOL, I missed that on the first read through, made me chuckle, I think. The dipstick should be under the seat I think? Goes straight down, has a twisty thing on top that tightens it in place like an old fashioned thermos bottle stopper (dating myself, but not as old as the cork stoppers)
Thanks for the help. sorry for the confusing post. I pulled the lever down and it did go into reverse. i quickly depressed the clutch and put back in neutral. I then tried forward but got nothing. that is the only time i tried the transmission since both buckets are down and i didn't want to drag them. I will be back down there Friday and try them out again. We have a hydraulic shop next to where i work so i will pick up hose from them to put it on. The transmission filter didn't look bad when i changed it and it has all new hydraulic oil now. I found the screen on the JD website. it says it's behind a fitting but I couldn't tell from the picture which fitting. From reading it looks like it should be behind a fitting that connects to a rubber hose. so is the screen behind the hose i'm about to change? sorry for all the questions, I'm not a mechanic, just play one on the weekends as i tear stuff up. Thanks again.
Yes, that sounds familiar. I don't know every model like some people do.
I don't know all that much to be honest with the exception of the old 510's, I cheat and look them up on the Deere parts website.... from the parts drawing it *looks* like the screen comes out the right side of the case, I think the hose you're working on dumps into the left side on the left end of the strainer but I can't swear to it.
The screen I'm going to change goes into the right side of the transmission if you are sitting in the seat facing the motor Here is a picture
Sorry my picture uploaded upside down
If you find the screen and it comes out, that's it, there's only one of them as far as I know. It will be plastic a little more than an inch diameter, maybe a foot long. Unless the old ones were metal? If it doesn't come loose you might have to wiggle it loose, they fit a little tight and can get jammed with debris. If it's not behind that hose fitting, then look for a 1 5/8" hex head plug somewhere on the side near the bottom. Or wait, is it a round plug with a big diameter, but a half inch square drive?
I'm kinda turned around on this machine, if that hydraulic filter is on the right side, then the screen is most likely behind that fitting the ugly hose is connected to? Delmer, I can't recall on those screens, I know the replacements were all plastic, I *think* I remember a plastic body with bronze metal wire screen in one old machine I worked on but I won't swear to it. The loaders used the same setup in the transmissions too as I recall.
My picture is upside down. If laying underneath the tractor looking to the rear. The hydraulic filter is horizontal on the left side. The hose runs to the right into the transmission beside the vertical transmission filter. If the tractor is driving north all this is on the east side of the tractor.
I picked up a piece of 1" hydraulic return line. I went down there this afternoon to put it on. Pulled the old on off and it had started separating on the inside and was about half collapsed. When I pulled the hose off just a little hydraulic oil came out. Then pulled the screen and it is behind that hose fitting, as I was pulling it out all the hydraulic oil started flowing. Cleaned the screen out but couldn't figure out what was clogging it up? I then pulled the hydraulic filter and it had broken apart and the media was coming out. That's when I put 2 and 2 together and figured out that's what plugged the screen. I then found the dipstick and filled it up full. All my hydraulics came to life!!! Thank you both for all the help. A $10 filter and some hydraulic oil was all it needed. Thanks again for taking the time to help me out. Here is a picture of the screen.
That's ugly! Guessing some water got into it at some time, the filter caught it but slowly came apart. Anyway, glad you got it going! :drinkup
Would you recommend running it for 10-20 hours and change the filters again?
Wouldn't hurt. I think what with cleaning the screen and all fresh oil you should be in good shape, but cheap insurance right.