Loader TC55 + 18LA Soggy noodle bucket syndrome

[sirloinofbeef]

I have a 2005 TC55 + 18LA with about 300 hours on it and I am the original owner of the this tractor. For as long as I can remember I have had issues when using the loader to move dirt. At first I thought I just sucked as a tractor operator but then more experienced guys had the same issue and complained about my equipment. During use, the cylinders that control the bucket become floppy. By this I mean the shiny rods move in and out of the cylinders when the control valve is not in use allowing the bucket to freely move up and down. When digging this results in either an empty bucket because it just rode up over the dirt or a huge hole in the ground because the front edge grabbed and tipped the bucket down for a very aggressive bite. Originally I thought I was getting air in my system and that this was responsible for the soggy noodle bucket but I have proven this wrong. The issue is that there is actually a vacuum in the cylinder as proven by cracking the fitting on the cylinder and air was sucked in not blown out. I can exaggerate this issue by filling up my bucket with dirt, lifting it a few feet of the ground and then dumping it quickly with the engine either idling or off. When dumping I am using the first position for normal dump rather that the second è¿*egen fast dump position.

I think I have proven that the issue is caused by a hydraulic demand that the pump cannot deliver, under normal use my engine is obviously not off or idling, this was just to prove my theory.

So my question is, do any of you other TC55 with 18LA loader owners have this same soggy noodle bucket problem, is this just how this tractor is or is there something wrong with mine?

 

[RDrancher]

Welcome to TBN!

I don't have an answer for you, but no, its not normal. Usually the only time you'll get a floppy bucket is when you dump and then try to backdrag without moving the joystick. I'm sure someone with more knowledge of hydraulics will be along to help solve your problem.

 

[DieselMonk]

I have a 2004 TC55DA with an 18LA now at 505hrs and do not have that problem. If I can remember correctly I had a leak down problem on the front bucket within the first 100 hrs. The dealer (under warranty) installed a orifice into the hydraulic line, but that didn't fix it. Then he changed the packings inside the cylinders and everything was fine. Did you change hydraylic fluid and filters?

 

[sirloinofbeef]

I too had a leak down of the bucket early on and had the seals/packing replced and that fixed mine too. I just did fluid and filter as the dealer sugested that may be the problem but its no different.

So on your loader you can dump dirt in the first valve position at idle and still have a firm buckett if you push it on the ground?

 

[Hooked_on_HP]

I am guessing that you have a blown internal seal in one of the dump cylinders. Run the loader for a while and then check the tempeture of the dump cylinders. The bad one will usually get warmer than the good one.
Bill

 

[jinman]

I know of one other person who had almost the exact symptoms locally and a couple of others have reported similar problems on TBN. The local dealer wanted to put an orifice inline to slow down how fast the fluid could escape from the rod ends of the curl/dump cylinders, effectively slowing down bucket dump speed. I think the problem is in the joystick valves or main pump not supplying enough fluid and is probably related to your slow engine speed. You only have full flow and pressure when your engine is above 2000 rpm. Many of us with HST transmissions run our engines at 2000 rpm or greater continually and vary the speed of the tractor with the HST pedals. This keeps the power steering and main hydraulic pumps working at peak efficiency. On the other hand, I've tried to reproduce those problems on my FEL and cannot. It is solid as a rock on my TC45D (built in 2000). The later tractors with loaders built by Alo-Quicke seem to be the ones where this problem shows up. I don't know that for a fact, but I never heard of the problem until NH gave Alo-quicke the OEM contract.

 

[DieselMonk]

yes. no problem. Did you get the orifice installed?

 

[sirloinofbeef]

I didn't get an orifice installed. Seems like this a a common theme and would make sense, where did they put yours? Jinman's feed back would suggest on the bucket end of the dump curl cylinders but this would also slow down the dump when the regen valve in joystick was open "hard over to second position". As I understand it the regen valve is basically a check valve that allows fluid to flow from the bucket end of the dump/curl cylinder to the tractor end but not the other way. Would it not have made more scene to have put this valve between the power port and tank port of the joystick as this would have allowed escaping fluid from any cylinder to supplement the incoming fluid any time incoming pressure was lower than the tank port pressure i.e. dumping a bucket at low rpm with low pump volume?

There is another little box of tricks on the machine that is called the "COMBINATION SYSTEM RELIEF - DIVERTER VALVE". I can find very little documentation how these things actual do what they do but they are different between the SSS and the EHSS. The EHSS appears to have 2 additional hydraulic pumps on it, one for the main tractor clutch and the other for the PTO clutch. The diverter valve on the SSS has to manage the distribution of fluid to the PTO clutch, Loader, 3pt Lift and rear remotes, the EHSS valve does not have the PTO port on it, as the PTO clutch has its own pump, and as such seems to be a lot simpler "See attach pics". My new theory is that on the SSS model when dumping the bucket with low pump flow a vacuum/low-pressure is created by the dump cylinders being drawn out rapidly due to the weight of the dirt. This low pressure, lower that atmospheric pressure, makes the pressure of the PTO port, that is just recirculating as it is not in use, appear high. High pressure signify demand so the priority valve "not present in the EHSS" tries to send fluid to the PTO port, further staving the loader of its fluid and creating a vacuum within the demanding cylinder. This vacuum, as proven by cracking the hoses, is the condition I loving refer to as the soggy noodle bucket syndrome... I can actual create the same condition in the main loader by lowing it rapidly and then dumping the bucket once it is on the ground. Instead of the tractor lifting up, the loader moves up without the tractor creating the soggy noodle loader syndrome but this is a lot less annoying...

 

[DieselMonk]

I have the EHSS model. My dealer installed the orifice right at the quick coupling for the dump. so yours is the sss model? Does your soggy noodle syndrom appear when the tractor is cold or only when the oil is hot?

 

[jinman]

Sirloinofbeef, I don't think that your problem is associated with the system relief and diverter. The system relief valve just sets the hydraulic pressure at about 2500 psi and the diverter sends fluid to the FEL joystick valves first if a loader is installed. The one for the SSS seems to incorporate the priority valve into the same block. On my tractor, they add a priority type valve to supply 0.8 gpm flow to the PTO clutch. It's bolted onto the relief/diverter valve. That one looks like it just contains all three functions in the same machined block.

I don't see much difference to putting the orifice on the actual cylinders or on the quick couplings as long as it's on the right side of the curl circuit as DieselMonk describes. Either way should work.