Hi all. I have a d6r lgp dozer that i have just put a new hydraulic pump and left blade lift cylinder on. Had a cat mechanic diagnose faulty pump low pressure and noisy. Blade lift cylinder bent and full of metal. After fitting new cylinder and pump blade still creeping down. Removed both cylinder rods from blade found rh lift cylinder creeps down and left stayed up. Removed rh cylinder rod and found metal on piston and cylinder scored also rod is bent towards the bottom. Obviously i need to replace rh lift cylinder. My worries are can the metal contaminate the new hydraulic pump and also can the metal have gone across into the new LH lift cylinder?? Any help would be much appreciated thank you!!
Well, your problem is rather complex, as a contamination of any kind in an HYD system is really a nightmare to clean... Usually all the oil that comes from jacks passes throug the valve bank, and in the case of lift cylinders some other automatic valves within the bank, only then goes to reservoir. The system can deal with some debris in it, but those piston pumps don´t like contamination, at all. It it was mine i would clean up the oil reservoir all contaminants, and flush system with diesel fuel or cheap oil having the return to a drum, cycle it and operate systems to detect any fault using old pump, after that put everithing back toguether and pray.
We had an excvator get metal contamination in the hydraulic system. I helped the dealer shop remove all the components that used hydraulic fluid we cleaned it all, tubes/lines, pumps, cylinders everything, likely was a very costly deal. And that is what you will need to do, if you want to do it right, fun times coming.
Since the machine has been run and operated the answer is yes and it will require a complete system disassembly, including cleaning the cooler, opening up the tank and individually cleaning every hose/steel tube on the machine, to get all the contamination out. You have a big job in front of you. Oh, and there is also the distinct possibility that the newly-replaced pump could also be toast.
Sorry about your D6R. Nothing that a pile of money can’t fix. I’m sure the new pump is trashed and the entire system contaminated. Welcome to the HEF. Keep us updated
Welcome to HEF! My condolences on your dozer issue.
Come on, shouldn´t be that bad, there are filters in the system, and usually damage is done by a single chip or two Got to have luck....
Yes there are filters but in that case why is the OP finding piles of particles in the cylinders.? Any contaminated hydraulic system should be stripped down and completely cleaned if the repairs are going to last.
Oh bugger. Thanks for the info. I removed new LH cylinder contaminated with metal after only 30 minutes operating. I have removed tilt cylinder all in very good order and no metal. Could i remove the hydraulic block on the bonnet and connect the 2 steel pipes together and cycle blade lever foward and back for say 5 minutes each way to make sure all contaminants would return to tank and be caught in filters?? After this than refit new rebuilt rams. I know its not what you recommend i just feel the damage may be done after 30 minutes of operating already i dont have much to loose. Thank you
You can, but unless you can prove that pigs can fly it is highly unlikely to achieve its intended purpose. My first suggestion is to replace the implement hydraulic filter. Take the filter element you removed and cut it open for inspection. Here is a VIDEO that shows you how the process works. Yes I know that it is an engine oil filter but the method is the same. I suspect you will not have a filter cutter so use a pair of tin snips or similar. Post photos of the catastrophe you find in the pleats of the filter media.
Why do you not the time or funds to repair this machine right, but you have the time and funds to repair this machine twice, three, four, ............? Every single component that touches hydraulic fluid on this machine needs removed, disassembled, thoroughly cleaned, and reassembled. Then it needs a few hours with a kidney loop while running. Any other repair process is a pipe dream.
If I could like the above post more than once I would....
It's like a virus in our body. It gets everywhere, but it's metallic and the machine can't recover on it's own with time.
Countless oil systems working with just a flush... As an add on, small particles are really the ones that kill systems. BTW actuator barrels can live well with some scratches. That beeing said, its time to say "the best course of action is to clean everithing" but if someone wants to try other option "its been done and very often goes well".
Been through this problem many times, all you need is luck on your side I think the danger part is lines that are linked to 2 cylinders, it stand to reason that any crap in 1 cylinder will soon be in the other cylinder, plus the hoist cylinders have recycling valves for the quick drop as well as check control, one of my customers had me remove a pump off his Excavator that had smashed up the rotating assembly's, I stripped and rebuilt the pumps with new parts , he had drained the hydraulic tank into a Barrel and cleaned out the tank by hand fitting new filters to the system, I fitted the rebuilt pump set back on the engine to then have to look on as he pumped out the barrel of drained oil back into the tank being careful to leave about 5 Gallons in the bottom of the barrel, it's not for me to tell people what to do but the Excavator has worked for around 3 plus years with that crap oil in with no issues, on the 6R I would have at least stripped out both cylinders, and all valving and pipework back to the 2 feed lines and blown oil down them into a clean pot to check for crap, then drained the tank and cleaned it fitting new filters and give it a go, a total strip out is a massive task on Site giving more chance of letting in dirt than getting crap out.