Year and some feedback on a Komatsu PC300LC-5LC

[Homer Dokes]

Hey all. I believe I have found an excavator to purchase and use on our development. It's serial number is A30206. Trying to determine the year tho I believe it is between '93 and '95. If so it would make it the newest piece of equipment I would have outside of my 2002 JD 260 skidsteer.

This unit has been sitting for approximately 3 years and for good reason. It spun a connecting rod bearing. I had been aware of this machine for quite some time as it has been on the market for a year. I steered away from it as several of you are aware I have spent a lot of time fixing when I need to be digging and moving earth. What I really didn't need was another project. Had a few excavators come up for sale in my neck of the woods but by the time they would respond to my inquires the units were already sold. It has been difficult finding something near by and in the price range I can handle at this time.

Made the decision to go take a look at it and arranged to meet the owner yesterday. I'd had a conversation with one of my operators that if I could find the engine was easily accessed and the oil pan easily dropped I could probably replace the bearing from underneath and get the machine going. When I arrived I found I was at a commercial development site and the owner was there waiting for me. Followed him to the excavator in question and from the get go noticed that the oil pan was actually sitting on the ground underneath the machine. That told me it was easily gotten to. Then the owner took me to the cab of the machine, grabbed a box, and found he had a complete set of bearings for it already. He just hasn't had the time to work on this machine himself as his profession is general contracting civil infrastructure work on commercial developments. It was his development we were sitting on. The two of us hit it off right off the bat and long story short... he's been doing this for over 40 years, is a couple years older than I, and when we finished our conversations two hours later he had agreed to come out and look at my development and to act a mentor on it. Do I need to say it was a GREAT day yesterday?

I looked over the machine afterwards as he had to get going... knew what I was looking at and for and I am certainly capable of getting the engine back together and the price is right that if it only lasted long enough to complete my project it would be well worth it.

What makes this purchase even sweeter, is unlike all the other equipment I have purchased which parts can't be had for... this excavator has all kinds of parts readily available for it. It will need a new undercarriage before to long but I have already found sprockets and rollers and reasonable prices. I really don't see how I could go wrong on this purchase and have made an offer to the owner and am just awaiting his acceptance or counter.

So... back to my original inquiry. Can anyone tell me the year and can any others speak to the machine itself? It does have a narrow deep bucket on it, he had already sold his 42" so I will need to search for another bucket if I do buy this unit. How interchangeable are the buckets from one mfr to another?

 

[Chiefdug]

Sounds like you fond the right deal at the right price. Me being a bit of a perfectionist, I would most likely take off the couterweight (if its an advantage, I only have experiance with Hitachi) pull the motor and get the crank turned. Then you know what youve got. My experiance with just replacing the bearings (which is very few times) has not been successfull. Just my two bits worth. Good luck.

 

[bccat]

It’s not simple job to just drop the pan and change out a rod brg, there is a lot of what if’s. Best to pull the engine and do it properly

 

[skyking1]

I try to stay out of threads like this, but I will say.
The model years mean nothing. You get parts by serial number so knowing the year is just a wasted effort.

 

[Homer Dokes]

The model years mean nothing. You get parts by serial number so knowing the year is just a wasted effort.

Unless you would really like to know the year.

 

[SteinarN]

IF it has a spun rod bearing then both the crankshaft and the con rod are in bad need of refurbishment/grinding. Replacing the bearing only is doomed to get you in truble VERY soon again.
Pull the engine and do the job properly and you might get a very good machine for cheap + some work.
Granted it is some additional work, but the other alternative is a machine with an even worse engine after a couple hours running.

 

[Simon C]

Is the engine in that one a Komatsu S6D125 series or is it a Cummins 5.9 Series engine. Some parts are harder to get on the Komatsu stuff or not available at all.
Dot your I's abd cross your T's before getting into it too far.
If the bearing on journal spun, good likely hood of a heat crack that you won't be able to see and broken crank some hours after.
Simon C

 

[Coaldust]

I’m going to be doom and gloom. Good luck with that S6D125. I like them, but they are super expensive to repair in 2025. “Rolling some mains” ain’t going to fix it.

I love the 300HD/LC-5. Great machine. Even better on a 400 underneath and Pierce Pacific guard package. Now, you got something. Just keeping it real up in here. Knowwhatimsayin?

 

[Coaldust]

Good luck, I tip my tin hat to your noble cause. The Tongass has never been the same, since.

We got the logs out of the woodz with those -5’s. I tell you what. They had their moment in the sun. Those were the dayz.

 

[Coaldust]

Interesting, you might check to see if a soft swing circuit was ever installed on it. These machines catered to the JDM market. In those days, we had to install our own soft-swing circuit because, that’s what our operators wanted.

Komatsu engineers be all like, “ you dirty logger, you no operate like that”. “You stop swing, then you boom”. Don’t you read instructions ???”

Hold my beer and watch this, Haruto……..

 

[Nige]

I really don't see how I could go wrong on this purchase and have made an offer to the owner and am just awaiting his acceptance or counter.

Unless parts for the engine are unobtainium, including a crankshaft if necessary. That would be a bummer.

 

[JaredV]

Just do this and you'll be golden.

 

[Coaldust]

Right on! Safety flip flops, too!

 

[skyking1]

that guy has some really big hands.

 

[Homer Dokes]

Hold my beer and watch this, Haruto……..

lmao!!! I get the point guys. If this machine lasts long enough to complete a 3 acre pond and storm drains I'm a happy camper. I have not committed to it yet and I won't until I have assured myself that it can. The owner stated that it lost the bearing while going down a steep hill with it. Stated it wasn't having issues at all prior to that. Assumes oil went to one end and that the pickup couldn't get enough oil in the system as a result. Looking at the crank case I could see the pick up was at one end of the oil pan. I have a seasoned heavy equipment mechanic that is going to go look at it with me.

 

[Shimmy1]

lmao!!! I get the point guys. If this machine lasts long enough to complete a 3 acre pond and storm drains I'm a happy camper. I have not committed to it yet and I won't until I have assured myself that it can. The owner stated that it lost the bearing while going down a steep hill with it. Stated it wasn't having issues at all prior to that. Assumes oil went to one end and that the pickup couldn't get enough oil in the system as a result. Looking at the crank case I could see the pick up was at one end of the oil pan. I have a seasoned heavy equipment mechanic that is going to go look at it with me.

Excavators usually have very deep, center sump pans. Since the engine is usually mounted transverse in an excavator, it wouldn't think going straight downhill would be a problem unless it was way low on oil. If that machine has a Cummins 8.3 in it, I might think there was a problem in the oil cooler/filter base that starved it for oil. The 8.3 in Magnum tractors is known for having casting flaws in these.

 

[Homer Dokes]

Ok.... seriously looking to commit. I have provided a contingency to the owner. I have to be able to get the engine up and running before purchasing and moving it.

For those who are not awful fond of the S6D125 motor which is in this beast... would this not alleviate your concerns regarding parts availability for it?

S6D125 Engine Overhaul Rebuild Kit for Komatsu PC300LC-5 Crawler Excavator | eBay

Komatsu S6D125 Engine. Type: Engine Overhaul Rebuild Kit. Included in this kit Applicable Models for 1 x Crankshaft Bearing Set STD size. 1 x Connecting Rod Bearing Set STD size.

www.ebay.com

I am also able to find undercarriage parts and external engine parts as well.

 

[Coaldust]

Stranger danger, Mr. Homer Dokes.
Unbranded parts shipping from Hongkong China?

We’ll be watching this train wreck. Keep us posted.

 

[Simon C]

Ok.... seriously looking to commit. I have provided a contingency to the owner. I have to be able to get the engine up and running before purchasing and moving it.

For those who are not awful fond of the S6D125 motor which is in this beast... would this not alleviate your concerns regarding parts availability for it?

S6D125 Engine Overhaul Rebuild Kit for Komatsu PC300LC-5 Crawler Excavator | eBay

Komatsu S6D125 Engine. Type: Engine Overhaul Rebuild Kit. Included in this kit Applicable Models for 1 x Crankshaft Bearing Set STD size. 1 x Connecting Rod Bearing Set STD size.

www.ebay.com

I am also able to find undercarriage parts and external engine parts as well.

I have done a few completes of these engines, the aftermarket parts are terrible at best compared to original and fuel pumps and some other parts including wiring harnesses are gone. Parts suppliers can tell beautiful stories till the installing mechanic finds out the parts you just spent $2500 on do not and will not ever fit. They can not even make a gasket properly on more than one that I built. Had to die grind head bolt holes in head gaskets to fit the pattern on the block.
That was with KMP parts which are about the best for Komatsu. I could talk on the phone for 4 hours straight about the last old D155A Komatsu motor I rebuilt in 2023 and all the problems we encountered with it and the parts problems.
All the best to you. I would run and never look back. Same year for a Cat I would look at maybe.
Simon C

 

[Simon C]

Ok.... seriously looking to commit. I have provided a contingency to the owner. I have to be able to get the engine up and running before purchasing and moving it.

For those who are not awful fond of the S6D125 motor which is in this beast... would this not alleviate your concerns regarding parts availability for it?

S6D125 Engine Overhaul Rebuild Kit for Komatsu PC300LC-5 Crawler Excavator | eBay

Komatsu S6D125 Engine. Type: Engine Overhaul Rebuild Kit. Included in this kit Applicable Models for 1 x Crankshaft Bearing Set STD size. 1 x Connecting Rod Bearing Set STD size.

www.ebay.com

I am also able to find undercarriage parts and external engine parts as well.

We had to buy exhaust manifolds for the last one from China. Beautiful looking. The bolt holes were 1/2 inch out and they have been recycled in the steel bin and no they did not pay back.
We bought through a fuel injection shop Parts for a fuel pump from England for mega bucks, but they were genuine and worked 100%. They were the last ones to be found anywhere. China had all kinds but non of the shops would buy cause they were no fit junk.
Simon C