Komat'su PC60-7 --Just Purchased Used--Some Questions

[Mark A Weiss]

Clear vinyl hose is a good replacement for the sight glass. I have one on a hydraulic tank that is pressurized to 15 psi.
Another option for the broken bolts.↓
If you have the room, cut that nut off with an angle grinder or, drill a hole next to those broken off bolts and use a new nut and bolt.
An angle drill may be a good choice for a drill.

Any recollection what size hose fits that sight glass fitting? Maybe I can pick some up at Home Depot hardware.

My neighbor wants to have a look at the bolts. He thinks he might have a way to get them out.

As for the whirring noise, I added 10 gallons of AW46 (all I could get my hands on locally in a hurry) and the noise is reduced but not gone. I compared a GoPro video of me using this excavator last week and there was no such noise audible at all.
I added the fluid, which brought the level way up near the filler, and then exercised all of the tools, including the tracks, but the noise does not go away completely. It's even audible when I run the fuel lever at half position while doing nothing.

I bought a hand cranked pump that attaches to 55 gal drum and I just need to buy 1" hose to come off the pump and feed to the machine tank, and of course the 55 gal drum of hydraulic oil, and then I can flush the system and change the filter.

The whirring sound is concerning though. Never noticed that before last night's change of the forward stick pilot line. In all other respects, the hydraulics work normally. Just noisy now.

 

[John C.]

There is a strainer in the hydraulic reservoir that when partially plugged can make that whirring noise. It's in the video. Those pumps do make some noise anyway so it may be normal.

 

[Mark A Weiss]

There is a strainer in the hydraulic reservoir that when partially plugged can make that whirring noise. It's in the video. Those pumps do make some noise anyway so it may be normal.

I just got done cleaning that strainer and checking the paper filters on both sides of the tank. They're all pretty good as far as I can tell.
The O-ring was completely gone on the filler side, so I made a temporary seal with silicon bead around the trench that the O-ring sits in.
Started up the machine, but no change in noise. Still whirring.
I now need to consider the possibility that the reservoir is over filled, too. Without a sight glass, I can only guestimate that the level may be above the full line.

 

[Tags]

Mark, please don't take this the wrong way, but you need to start taking the advice people are giving you. John told you EXACTLY how to figure out how much fluid you need without the site glass. Stop just doing things that may not need to be done, it will cost you more in the end. Slow down, and get the right amount of fluid in there BEFORE going any farther. Get the proper filters and o rings, if an o ring is missing don't try to "make a seal with silicone" it won't work and chances are it won't seal well and particles could get past and do some real damage to your hydraulic system. I know having a machine is exciting and can also be very frustrating if things aren't going the way you'd hoped, but take your time and get it squared away correctly and it will last you a long time. The amount of knowledge and free advice given on the site is incredible and is from folks that have been around this type of equipment most of their lives. The advice given here will save you tons of grief in the end, but you need to apply said advice.

 

[Mark A Weiss]

That's why I'm here.. where the experts are.
That old oil needs to be flushed. It's the color of coffee with milk. I reckon mixing AW68, AW46 and whatever's in there didn't do it any good either.
My manual indicates there's a drain plug under the tank. I just need to figure out where I am going to store 25 gals of used hydraulic oil.
Oil's much cheaper by the 55 gal drum, so I'm looking for a supplier that can forklift said drum onto my truck. I bought the pump already--just need hose.

I want to replace the rubber hose that's currently where the sight glass should be, when I flush the system.

Getting the filters is something I don't know where to shop for. Does it go by excavator model, or is there some generic size I need to match?

What size clear tubing do I need for replacing sight glass?

Who sells AW32 by the drum in the Danbury/Brookfield area? Where do you folks buy your oil in bulk?

How do you capture the old oil and what sort of containers are used?

I know it's a lot of questions, but I'm convinced there's water and air in the hydraulic fluid and that's causing aeration in the pump. Didn't see any metal particles in the strainer, so that's good news.

 

[mutti_wilson]

That's why I'm here.. where the experts are.
That old oil needs to be flushed. It's the color of coffee with milk. I reckon mixing AW68, AW46 and whatever's in there didn't do it any good either.
My manual indicates there's a drain plug under the tank. I just need to figure out where I am going to store 25 gals of used hydraulic oil.
Oil's much cheaper by the 55 gal drum, so I'm looking for a supplier that can forklift said drum onto my truck. I bought the pump already--just need hose.

I want to replace the rubber hose that's currently where the sight glass should be, when I flush the system.

Getting the filters is something I don't know where to shop for. Does it go by excavator model, or is there some generic size I need to match?

What size clear tubing do I need for replacing sight glass?

Who sells AW32 by the drum in the Danbury/Brookfield area? Where do you folks buy your oil in bulk?

How do you capture the old oil and what sort of containers are used?

I know it's a lot of questions, but I'm convinced there's water and air in the hydraulic fluid and that's causing aeration in the pump. Didn't see any metal particles in the strainer, so that's good news.

I use my oil to fuel brush fires. Fastest way I've found to get rid of it.

Filters will be specific to your machine. You can cross reference them if need be as well.

 

[John C.]

The color of the oil doesn't mean a thing. It's the clarity. Put some in a glass jar and hold it up to a bright light. You should be able to see the light through it pretty easily. You might also consider getting a sample of it tested. You can get test kits from any Cat dealer and there are third party labs, usually affiliated with the oil supplier that can test it for you.

If you wish to drain the oil out of the tank, go get a barrel pump and put the suction end in the tank and pump the oil into a barrel. It is nothing but a mess trying to drain the fluid into a drum from the plug underneath.

 

[Welder Dave]

Most places that do oil changes on vehicles will take your used oil or your municipality may have an Eco station where you can take it. Silicon is no replacement for an O-ring. If even a little bit gets in the system can really screw something up. Take Tags advice above and slow down and fix things properly before you try to do little jobs in between. I don't think mixing different viscosities of oil is going to do much damage especially if you're going to be flushing it out. You're creating extra work and expenses the way you're going. A lot of the stuff you're asking you need to figure out yourself such as the length and size of the vinyl hose for the oil level. It can't be very long so buy a couple sizes if need be and see what fits. Probably cost about $2. Filters you should know are specific to a machine the same way they are on different vehicles. If you can pump most of the oil out is less mess and then just drain the last little bit in a pail. Might want to look for where water could be getting in the hyd. reservoir. That might be why the oil is milky looking. Owning equipment means sometimes you have to figure out how to do a lot of your own repairs and maintainence unless you can afford to call a mechanic out every time something needs fixed. This forum has a lot of experience but can only help you so much without someone being there in person.

 

[Mark A Weiss]

The clarity is milky. I don't trust it. The guy who owned it before admitted he'd never changed it.

I gather that there must be changing positive and negative pressure on that O-ring, hence the danger of silicon bits getting ingested into the pump?

I think I found a suitable O-ring. The diameter of the trench that it sits in is 5-3/8". The ID of the ring I found online is the same, so it probably will fit.
https://www.amazon.com/dp/B0051Y2HE...olid=1SLUN1HP12CCU&psc=1&ref_=lv_ov_lig_dp_it

I'll head to Home Depot and buy a bunch of clear tubing of different sizes. I also need 1" ID hose for the barrel pump I bought yesterday.

The filter is expensive. I found an exact visual match on eBay for over $60... oh wait, it's coming from India:
https://www.ebay.com/itm/284199714121?hash=item422b9f7d49:g:TgcAAOSwJTNgOfVj

This one's much cheaper and is shipped from MN but it looks slightly different than mine:
https://www.ebay.com/itm/324497630244?epid=1928858524&hash=item4b8d90e424:g:dJYAAOSwgvdgNqq9

Still not sure about the paper pleated filter (blue arrow).. can't find a description in the manual.


The one thought that nags me is why did the hydraulics become noisy after I changed that second pilot line?

 

[Bluox]

The blue one is a screen there Ace I bet it's a couple hundred .
Most of the time it can be cleaned.
Bob

 

[Mark A Weiss]

The blue one is a screen there Ace I bet it's a couple hundred .
Most of the time it can be cleaned.
Bob

On mine it looks like a paper pleated filter. The red arrowed one has the metal perf outer layer and maybe pleated paper internally, plus a removeable strainer.

Today I removed the (fiberglass?) cover that is over the tanks and replaced the sight glass. It was a deformed piece of clear (not so anymore, as the former owner painted over it when he painted the machine). Turns out to be 1/2" tubing, so I got some at Home Depot. The only thing is, the new tubing has a thinner wall, and no matter how much I tighten the compression fitting, it still seeps oil out the bottom.

With being able to see the level now, I put back some fluid until I had mid level on the site glass. Apparently, I had about 5 gallons too much in there yesterday. Now with the right amount, the noise quieted down significantly. Machine is working fine today.

I noticed that the coupling/joints that attach the bucket have a lot of play in them. Is this wear, or can it be tightened?

I moved the machine to the other end of the property to dig up an evergreen and move it. I noticed that the left travel stick is either on or off, there's no gradual ramping up of speed. Is that normal, or in need of an adjustment? It's jerky because I can't ease into it.

Still looking for a good supply of fluid and new filters.

My neighbor looked at the rusted in bolts and suggested I cut the studs off with an angle grinder, then tap and drill out the remaining stud. I bought a set of reverse spiral bits, some drill bits, etc. and will attempt one next chance I get.

 

[Welder Dave]

What's with the Ace... it's just more condescending crap nobody needs or cares for.

For Mark, you should have never bought the machine if you're going to be on such a shoe string budget. There's a reason heavy equipment is commonly referred to as a money pit. Get the proper filters for your machine. You don't go by what they look like or even the thread size. You go by the proper filter! If you think a filter is too expensive, price out a pump, wheel motor or valve that the filter protects. Little bits of silicon in the system could cause big problems, there doesn't need to be any kind of scientific description why. The blue arrow points to a suction strainer that typically doesn't need to be changed but can be cleaned. I have to change the water pump in my Cat and it will cost about $300 by the time I'm done. I consider that a victory. On equipment I figure if it's under $500 for a repair isn't too bad. I've had some repairs that were several thousand dollars that needed to be done. I wouldn't cut the bolt(s) extending through the nut(s) just yet. You may be able to use that extended part to thread the broken bolt right through. Check the linkage of your travel levers for dirt and and debris. So you went to use your machine again without making sure everything is properly fixed first. I'm sorry, I don't get it. You've got people trying to help you but you're not listening or paying attention. You may need to have new pins and bushings installed on the bucket and possibly other pivots, especially if the previous owner neglected to grease them on a regular basis...like everyday! This could cost a few hundred bucks to repair. You went in pretty blind on this machine and now you're learning all about the costs of ownership. It can be an expensive lesson.

 

[Bluox]

What's with the Ace... it's just more condescending crap nobody needs or cares for.

For Mark, you should have never bought the machine if you're going to be on such a shoe string budget. There's a reason heavy equipment is commonly referred to as a money pit. Get the proper filters for your machine. You don't go by what they look like or even the thread size. You go by the proper filter! If you think a filter is too expensive, price out a pump, wheel motor or valve that the filter protects. Little bits of silicon in the system could cause big problems, there doesn't need to be any kind of scientific description why. The blue arrow points to a suction strainer that typically doesn't need to be changed but can be cleaned. I have to change the water pump in my Cat and it will cost about $300 by the time I'm done. I consider that a victory. On equipment I figure if it's under $500 for a repair isn't too bad. I've had some repairs that were several thousand dollars that needed to be done. I wouldn't cut the bolt(s) extending through the nut(s) just yet. You may be able to use that extended part to thread the broken bolt right through. Check the linkage of your travel levers for dirt and and debris. So you went to use your machine again without making sure everything is properly fixed first. I'm sorry, I don't get it. You've got people trying to help you but you're not listening or paying attention. You may need to have new pins and bushings installed on the bucket and possibly other pivots, especially if the previous owner neglected to grease them on a regular basis...like everyday! This could cost a few hundred bucks to repair. You went in pretty blind on this machine and now you're learning all about the costs of ownership. It can be an expensive lesson.

Dave you are truly an equipment repair sexual intellect.
Bob

 

[John C.]

Mark, why don't you give a Komatsu dealer a call and ask for prices before trying will fits and crap sold on the internet. I bet an OEM hydraulic oil filter is less than what you would pay on the internet with shipping and waiting time. The sight glass isn't expensive to get the right one with the right seals and not have oil leaking all over your machine.

 

[Welder Dave]

The difference is I try to help people out without being a patronizing jerk!

 

[Kobelco ireland]

A quick story about why not to use the filter that looks right instead of the one you know is right. So three weeks into the training on my first mechanic job I was asked to service a little lister diesel engine by myself. Off I go into the stores and start picking out filters I matched the numbers for all except the engine oil filter, I did find one that looked the same, same size same thread said lube filter so I thought happy days. I changed oil and filters on the engine and fired it up. While I was giving myself a big pat on my back for a job well done the engine seized. Turned out the oil filter was not the same. It was a costly mistake. So the lesson is always make sure it is correct and not just 'ah sure it looks right'

 

[mutti_wilson]

A quick story about why not to use the filter that looks right instead of the one you know is right. So three weeks into the training on my first mechanic job I was asked to service a little lister diesel engine by myself. Off I go into the stores and start picking out filters I matched the numbers for all except the engine oil filter, I did find one that looked the same, same size same thread said lube filter so I thought happy days. I changed oil and filters on the engine and fired it up. While I was giving myself a big pat on my back for a job well done the engine seized. Turned out the oil filter was not the same. It was a costly mistake. So the lesson is always make sure it is correct and not just 'ah sure it looks right'

Did you find out why the wrong filter caused the seize? What was "wrong" about it?

 

[Kobelco ireland]

The filter had a rubber flap inside to stop the oil draining out of it. The oil on original flowed through the filter from outside to inside, on the filter i fitted the oil flowed from inside to outside. The rubber flap acted like a one way valve and stopped the oil flowing through the filter

 

[Mark A Weiss]

I thought I'd fixed all the original problems by getting the proper fluid levels, and the since the noise abated then, I figured, okay, we're in business again and went back to work.

The only issue at the moment, from an operational standpoint, is that left travel stick being on/off instead of variable speed (I don't remember it being like that a few days ago). Is it a valve that opens and closes thereby controlling the flow of hydraulic fluid to the control valve? Where would this linkage be that needs looking at? It seems pretty self-contained in one location with multiple hoses connected to it. I'm also not sure I tightened the fitting at the other end of the line where it goes into the control valve. It seems that it leaks a bit, and I will try to tighten it some more. It's in a spot where I can only access on a steep angle with an open end 19mm wrench so I can't get much rotation nor torque to tighten it really well. I'm thinking maybe that miniscule leaking might be causing issues.

As for the sight glass, yep, I'm not happy with it seeping fluid. Will have to find some thicker walled tubing and try again.

All of the joints are oozing fresh grease when I bought it, and the owner made it a point to tell me that he disable the automatic grease system so he does it manually with a grease gun. I purchased a grease gun last week and two canisters of Moly-Graph "extreme pressure" general purpose grease. I plan to lube all the fittings before next use.

The former owner said he gets all his replacement parts on ebay for a lot less money than buying from Komatsu and suggested I do the same. I realize there are situations like with the oil filter having a check valve that can cause catastrophic failures. I have to be careful to make sure they're selling genuine products, if I go that route.

I put in a contact request with Komatsu a week ago and have not heard back from them yet.

The filter I pointed out in blue arrow IS paper pleated on my machine. Is that the wrong filter that the prior owner put in? It was said that this is supposed to be a strainer. But the strainer is inside the filter on the side with the red arrow. That filter has a metal perforated outside layer. I want to make sure I put the correct filters in. I know it's critical to the lifespan of the pump.

 

[Vetech63]

This is going 65 pages +.............bet the farm guys!