I have a question for the experts out there if you would be kind enough to advise me, I bought an old komatsu pc 180 to help me do a few jobs around my farm and its been ok but I had a mechanic come to look at it because it was overheating he seams to have solved that but he was also doing something to some valves or something which seams to me to have put the engine under more stress, when I use it it makes the engine struggle and smoke, to lift the bucket full it almost stalls the engine but to dig with isnt to bad, to push the arm away from you makes it smoke a lot, certain actions are worse than others. The mechanic was very young and I got the impression he wasnt sure about what he was doing and my french wasnt that good to question him about it, so I've used the digger on and off since , i'm worried that if I continue like that I will do some serious damage to the engine, I dont care if it works slower but I need to try and relieve the pressure if its possible, so if there are any adjustments I can make could anyone please advise. It does seam to be using more oil so I was wondering wether this could be because of that or because the engine is simply worn out ?? Although I must say it starts perfectly the second you turn the key and sounds good too. Any help would be greatfully apprieciated. Stewart.
what series is your PC180? I mean a dash 5 or 6 series. If its a dash 5 series, the problem is probably in the opening of the main pump's swash plate. ( possibly always in full stroke). There's a sensor in the side of engine's bellhousing that monitors the engine rpm, this sensor gives input signal to how the swash plate should stroke. Check it first.
The Dash series and a serial number would be very helpful. The nice thing about Komatsu is that you can adjust them to any operating style you want. The bad thing about a Komatsu is that some noob the doesn't know what he is doing can screw you up real bad. You need to complain the noob's boss and get this straightened out quick. The engine won't take that kind of loading for very long. Good Luck!
Thanks Domsant and John for your replies, I had a feeling something like that could be the problem, does this help PC 180 LC 3 , Serial number K10349. I'm not sure what a "swash plate" is, I think that is perhaps an American name for it, I'll try and find out what they call it in English and French. The company went bust so cant do much complaining I'm afraid, Although I think I've found another company that might help , of course it helps a lot If I can understand what they are doing or not doing ! Thanks again, Stewart.
Ok I know what a swash plate is and does now, its a stationary angled plate, which angle can be adjusted to alter the speed at which the pump can pump at.
The Dash 3 series has a very rudimentary computer control system that uses a red and green diode for diagnostics. I don't remember where the box is located for sure. You should check behind the cab or in the battery compartment. Most of the boxes have a decal on the front that tells you what each light situation means. If the lights are not lit when the key is on the you don't have any power to the unit. What I suspect is that the noob disconnected the TVC solenoid valve. It is mounted on the pump. Follow the wires down to the connection and see if it is hooked up to the wiring harness. When that solenoid doesn't work the pump is in max output. Let us know when you have checked this and confirmed that the computer is hooked up and the lights work. We can then try and steer you down the path to get your machine working. Good Luck!
Ive had a good search for the diodes and cant find it, cant see anything inside or on the back of the cab, theres nothing in the battery compartment either exept for a round metal jam jar sized object that one of the battery leads is connected too and one or two other wires. I found the tvc solenoid valve and traced the wires into the loom so that seams to be connected.
Do you have a dial in the cab that says H, S, and L or does it just of S and L?
S and L
You machine doesn't have a computer then. If you disconnect the connector for the TVC solenoid, you should be able to check for voltage on one of the leads with a voltmeter. One lead will ground back through a resister and the other should be hot. If there is no hot lead, then the pump is always in max output. If you look at the TVC solenoid and the go to the other side of the pump you will see an adjusting screw. I'll bet the paint has been knocked off the lock nut for the screw. Let us know what you find.
I've checked the solenoid and am getting a reading of 12/13 volts ( I was expecting 24 as it has two 12 volt batteries) with key on and engine not running, with key off 00 volts. There is nothing the other side of the pump but on the same side as the solenoid there are two spool blocks, the one nearest the engine has the solenoid fixed to it. On the top each block there are three adjustable screws/bolts with locking nuts and a screw driver slot in the top of each one, one of the slots has half broken away so has probably been tampered with at some point in time.
The TVC solenoid is mounted on the end of a valve. The side opposite of the solenoid has a lock nut and screw. Is that the screw that is broken?
I'll take a photo and post it, to make sure I'm looking at the right part.
The round bit is the solenoid ?? and you can see on each block are three locking nuts on bolts with screwdriver slots, The one to the right of the oily one has the bottom part of the screwdriver slot broken off, not easy to see. Hope I'm in the right place ! :beatsme.
That solenoid attaches to a valve block. There is a piston inside the solenoid that pushes on a spool inside the valve. If you look at the end of the valve block opposite of the solenoid you will see an adjusting screw and lock nut. That is where you adjust the TVC pressure which controls the pump output. The adjustment also controls the output of both pumps put together. You might be lucky and be able to adjust the screw out to relieve some of the load on the engine. What I see in your photos is that your pump has been in there a long time. Generally, moisture gets into the ends of those valves and rusts up the adjusting screws and pistons causing them to freeze up. That is the usual reason the slots in the ends of the screws get broken. It is probable that the fellow who worked on your machine turned in one of the screws and pushed a stuck piston in and it won't come back. The cap with the screw can be removed and piston pulled out and cleaned up. However it looks like yours will be pointing down and there could be parts that might drop out while you are cleaning things up. I have stuck a magnet over the hole when I've done those and anything that wants to drop gets stuck on the magnet instead of getting lost on the ground. The entire servo control valve stack can be removed from the pump and overhauled but it is meticulous work that needs to be done in a clean environment with a service manual in hand. It is very easy to put valve spools and springs in the wrong way. Good Luck!
And I hope all that black stuff is from a previous bad muffler/exhaust system and not the current muffler/exhaust system.
Hi Willie, unfortunately it is from the current system, I was a bit shocked myself when I lifted up the hood myself and saw all the black, as I said earlier on the problem was putting the engine under to much stress and making it smoke, there must be a hole in the box somewhere so thats got to come off and be repaired or changed. We are in the process of building a new workshop which should be finnished before the winter, when I hope we can get it in and clean it all up and give it a new lease of life. And your right about a good mechanic, I wish I new one, I'll have to get John to come over for a couple of months, :exactly.
After you're done with him, and send him home, have him drop off a bottle of French red wine as he passes by me. The black exhaust soot is messy enough in pump and engine compartment, but the thing you need to watch out for is hot exhaust (from leaking system) melting wiring, hoses, and sensitive electrical components in the area.
The speed sensor wires are susceptible to that and as I recall there is a plastic tube going to an air filter indicator that commonly gets burned off. It's good to know I could find places to sleep if I decided to travel abroad. I'll keep it in mind if I ever make it to retirement. Hey Willie, I'd be happy to bring and share a good bottle of French wine but I've never had a passport. Maybe some Black Velvet instead?
Aww hell...why not. LoL :drinkup
Thats the trouble I have made to retirement a it hasnt made the slightest bit of difference, infact I think I'm working harder. Anyway have screwed the bolt out a few turns and it does seam to have taken a fair bit of stress off the engine, I'll test it out next week when I've got to dig out the floor for our new workshop, so many thanks John for your help and advise. By the way if you ever get a passport and come to Gascony in SW France, you come and see me and you can have as much red wine as you can drink, (After you've fixed the Komatsu) :bash And I'll give you some "Eau De Vie" or water of life, I call it fire water, Its distilled from grapes and is clear like vodka, it burns all the way down ! and you could drop some off at Willies on the way by. You could have a drop together:beerchug and end up like this:dizzy so I'll say:waving , until the next time.
I have one just like yours in Jamaica the problem you have is with the co and nc valves the are stuck needs cleaning and adjusting,the releive valve also can be stuck,best for you to have a work shop manual so you could know the diffrent parts
be very careful, do not attempt to adjust your co's or nc's unless you understand the functions of the componets...just sayin
Thanks for the last comments, Still waiting to get our workshop finnished then maybe we can get it sorted once and for all in nice clean conditions !
Gents, I have a Komatsu PC180 LC-3 year:1988. Are there still parts made for this machine? I'm looking for: -Shop/Service manual (online/free download) -Parts/rebuild kits (online purchase) Can any one help me where i can find these . . . . Thanks in advance
Hi, do you guys know how to take out both pumps oil flow to hammer or other equioment? PC180-3 I have only that "service" spool in my machine and there you can have only one pump flow out... But i am looking more flow, so any tricks how to do it? I try to search "hammer valve" and fuction/installation of that could not find anything Thanks! /Antti
The only way I got away with splitting pumps on a Dash 3 was to put diverters between the pumps and the main control valve. You will need to talk to a hydraulic supply house and they will know what you need and how to set it up.
Hello, Can somebody explain how to set up "basic" setting for this back screw? I have a problem that front pump is giving too much flow vs. spool postion, i can feel that engine is under load when use L.H traver motor slowly? And this L.H traver motor control is really aggressive. R.H travel motor controll is very smooth and bucket is very slow, so think rear pump flow setting is too low and front pump too high. So any tips how to set up both pumps in same level? Excavator is PC 180-LC3
Before messing with pump screws you have to make sure the down stream items are working correctly. Have you checked standard main relief pressures, pilot pressure, jet sensor reliefs, cut out settings, TVC pressure as well as the case drain flows on the two travel motors. Once you do all that then we can talk about adjusting the pumps.
All of those are measured and adjusted except travel motor case drain I had to set up TVC pressure littlebit lower than manual says because engine stall too much. I was wondering that engine might stall because front pump setting is not correct, maybe somebody have adjusted pumps to get more flow and now front pump flow is too much and rear too low. Also one what i was wondering is jet sensor pressure, because both pumps jet pressure did not act same way? Pressure difference was same but measured true pressures was different? -Antti
Jet pressures are used to control pilot pressure that controls the pistons that are attached to the swash plate. What I do is attach gauges to the ports that are on the end of what look like bolts. Those ports tap into the pilot control inside the pump. I adjust the jet sensor reliefs to get about 70 to 75 PSI on the pilot pressure inside the pump when the engine is at high idle and no load on the hydraulics. That pressure adjustment is referred to in the service manual as "Negative Control Pressure". There are small pistons on either ends of those adjusting screws and a lot of times rust and crud gets in there and freezes the pistons in place. I've also had the adjusting screws get frozen in place hard enough that they brake off. I don't know how long the machine has been running since it has been overhauled or rebuilt. The pumps are usually set up on a dynamometer when rebuilt before installation on a machine. Adjusting those screws in the field is usually a pretty touchy thing to attempt. What I have done in the past is remove the valve stack from the pumps and take them apart for cleaning. I've always just taken the bracket holding the screws off the block and left the screws at the same setting. Let me know what you see on the jet sensor adjustments.
Front pump NC pressure 80 PSI at high idle and no load, track raised and full travel 245 PSI Rear pump NC pressure 80 PSI at high idle and no load, track raised and full travel 290 PSI Why there is difference when full travel., shoul pressures be almost the same? How to adjust if needed because if adjust NC pressure, it will change both end pressures? Jet sensor front pump, high pressure side 320 PSI, low side 85 PSI Jet sensor rear pump, high pressure side 180 PSI, low side 5 PSI Have to say that i don´t get why there is difference and if needed, how to adjust this? Adjusting screws and pistons seems to be working. Thanks, Antti
Try to interchange jet sensor valve and measure again and see if values you measure before remains the same or not. So you can tell if problem is the pump or control valve.
You are on the right track. Book pressure is about 78 PSI. I generally ran them just a little lower to get better feel in the controls. 75 PSI works pretty good. The NC pilot pressure is the low reading with the engine at high idle and no controls moved. The high setting is the pump cut out pressure. Check the CO pressure with the boom raise function. Raise the boom all the way up and watching the gauges, bring the pressure up slowly. I watch to see if the cut outs read close to the same as I bring the pressure up through each 1,000 PSI reading. At somewhere around 3,500 PSI the pump pilot pressures should start to drop. When you reach the main relief pressure both pilot pressures should be reading about the same as the NC pressure. The cutout pressure adjusting screws are the top blocks on the stacks on the pumps. If you have a book it should give you a rough drawing of the valve. The travel circuits have a function called CO cancel which puts a pilot pressure on the back side of the CO valve and maxes the pump output. When you state the jet sensor rear pump high pressure side 180 PSI and low 5 PSI, are you measuring the actual differences on the lines coming from the main control valve to the pump? If so you probably need a new jet sensor relief cartridge on the rear pump valve. If you change it you will have to readjust the NC and CO pressures. Did you check your main relief pressures before checking the pumps. Those need to be set equal in order to get the same CO pressures.