Q. This is for the Mechanics in the group, yes I am new and this is the first post I have ever made on any forum... "Virgin I am!" Anyway the issue with this JD started happening on the last 1 year project we recently completed. As stated the boom 3 months into the project wouldn't lift or retract enough to reach the lock without dropping the exten-da-hoe and bucket to the ground to push the arm into full retraction and locked. I of course became aware of it nearly a month after it started and I went to take a closer look one quiet morning and at idle I could hear a slight hissing or leak in the valve body below the control podium, so I grabbed onto the left stick (raise and lower) for the boom on the main arm and ever so slightly began to ease it backwards (towards lock position) and at approx. 1/8 of an inch not even noticeable by eye, ear only... The hissing stopped. My intuition tells me because the issue is related to this very function and leaking by at that particular valve it must be the source of the problem. Well Balls to the wall over the last 6 months and no opportunity to fix the issue while working the 310 like a drunk date all day long has only resulted in nothing working in regards to locking the boom? Dropping the Xtend-a-hoe to the ground only picks the tractor up off the ground and doesn't work to lock anymore. The valve is hissing like a snake and I need some hard core advice as to how to fix the issue and lock this boom once and for all. SEMPER FI! Please Concur... Thank you.
Now just to clear up some feelings that came through in that last post, I wasn't calling the old (5) JD a tramp. I'm just saying she's loose, drips uncontrollably and wanders... Other than all that she is a real nice girl and takes it hard daily! Although my first and still true love is the Case... I have admired how the JD's take a beating as well, they just wear out quicker and will always be a beginner hoe in my opinion. Mainly due to the damn wobble sticks or beginner sticks! Those damn things suck and have cheapened my reputation as an operator because unlike the keys on both the ford (reversed) and Case (perfection) the wobble sticks don't detour any weekend warrior from talking his way into a position designed for skilled operators. The keys are the key! Its like the split brake peddle they all have, skips included. A real operator would instantly reach down and unlock them! I can attest to the fact that 98% of the operators I meet, work with or have worked with in the last 12 years don't know and can't operate the Case because they have only had those joy sticks and have never unlocked those breaks not even having a clue of the potential hidden beneath their feet! A shame really because its lowering the standards and the pay scale for what should be much higher paid for well versed operators. Case is indeed the Ninja of Backhoes and that foot swing will make you more dam money than 3 JDS digging one trench!
Hello and welcome to the forum. I realize you are new here and have probably not posted a picture. We all know what a backhoe looks like but still. .. a pictures worth a thousand words. It helps with recall of years, models, specifics, tricks etc. Also if you were familiar with posting pictures you wouldn't have to figure it out at the last minute. I say this because i still have difficulties. See ya on the Funway Fixo
Not knowing the year/model of you 310 and not knowing how every model is designed anyway, I am thinking it's possible that the piston in the boom cylinder has unscrewed and therefore making your rod/piston assembly longer. Once you tell us if you have an A, B, C, D, E, G or J someone may be able to help us with this.
If it's 5 years old then it's not an A or B, but I'm not sure that's what you meant? If you can't push the cylinder back to lock then as Deon says, the piston unthreading is the only possibility I can think of. IF that's the case then you're making metal inside the system or will be very soon, so I would call this urgent.
Thank you for the timely response to my issue, and please accept my appologies for the delay in responding to your request for more info. Please see that attached photo/image of the JD 310 SG which is giving us the problems. Note the backhoe arm resting on ground, 15 minutes prior to me snapping the photo it was fully retracted into the NEAR Lock position??? The prognosis or diagnosis received by all who responded sounds to be a real potential cause and effect. I will look into that and if you have any further advice please don't hesitate to elaborate.
As I mentioned earlier. Sounds like the piston nut is loose. If it is, then the hydraulic oil can pass between the piston and the rod end so can cause the boom to drop like that. So J Wow 69. You need to do some testing like try if it floats. Just set the bucket on the ground and use the extendahoe to push the boom up and down. If the boom cylinder is not firmly holding its position then that should confirm the nut is loose.