I have ordered some 90A FKM o-rings that I hope will be less prone to extrusion failure.
In the meantime, I realized that there might be a trick to installing this fitting in a way that reduces the chance of this type of failure. Since this side of the fitting installs into the pump...
I just checked discount hydraulic hose, and it looks like this fitting is a 5069L? Viewing the various sizes available made me realize that I forgot to measure the thread pitch while I had it off the machine. Guessing it is M22x1.5?
I also had the thought that this failure might relate to...
I just went out and pulled the fitting to measure the seal dimensions. This time, I brought my camera and took a photo of the failed ring in the fitting. You can see from the picture of that the O-ring was pushed between the gap between the backing washer and fitting. Again.
Based on some quick...
After more research, I believe that the pump outlet port fitting is DIN 3852-H (adjustable o-ring style); it has a locking nut, backup washer, and retaining ring. From that, I think a DIN 3869 profile ring (aka "D-rings") might be the best solution, particularly since the backup washer does not...
Unfortunately, I did not have my camera with me, and I was in a hurry to fix the machine to get some work done. So no pics this time.
After a little bit of research, this sounds like an "extrusion failure". I believe that the Viton o-ring that I used was too soft (probably 75A). At the very...
I had to tear down the machine to replace the o-ring again. Afterward, I took it out again for a few hours, and it started leaking again. Apparently, I need to find better o-rings?
I was double-plus careful when installing it, so I am certain that it did not get crushed. Instead, it seems...
I have tried to use this thread to document all the upgrades and repairs that I have made to my machine. I think I have covered the bases, but I hope others will chime in to mention anything that I have missed. In my original post, I compiled my initial list mostly by scouring the epic thread...
Today's lesson: not all o-rings are created equal.
As I mentioned earlier in this thread, my VC13 developed a leak at the output port of the hydraulic pump, due to the factory-installed o-ring deconstructing itself. I had replaced that o-ring with one that I had on hand, and it solved the...
Travel speed is definitely slow, but the swivel/arm controls are fairly responsive. With a full bucket at full extension, the arm will have enough weight that rotating too fast will easily lead to tipping over the machine. That's true even with my bigger machine, and the same kind of thing...
The weather has been cold and wet here for weeks, so I have not been able to do much since my last reports. I did finally finish installing the cushion valve for the swing motor, so it's now ready to do some real work (without fear of breaking those components). It's worth noting that working...
I used ISO 46 and 10W-30 in my machine for year-round use, as the temperature never gets really cold or hot here. In that regard, the best choice depends on your local climate; some people use different weights at different times of the year. For the engine, use a lower first (W) number in cold...
I am still working to find suitable hoses/fittings for connecting my cushion valve. My preferred hose shop looked at me blankly when I asked about DIN 2353 Light fittings, so I visited another local shop yesterday to see if they had what I need. While they had all of the required parts, they...
I also got around to installing the aux A/B valves today. I plugged the spare valve ports with the caps that originally came with the machine, both to keep dirt out as well as in case the valves get turned by accident.
While I was at it, I finished wrapping all of the hoses that go to the...
I tore down the machine today to investigate this issue. As the attached picture shows, the o-ring had indeed failed. From what I can see, it looks like this part was not made of solid material, but rather has a core with a skin. After replacing with a new one, that fitting no longer leaks, but...
I have not finished installing the aux kit or new tachometer, opting to get out and work on some projects instead. Gotta make hay while the sun is shining.
First, I created a new landing for a pair of claw foot tubs overlooking one of our ponds; these will be turned into wood-burning "hillbilly...
I ordered a few more parts for my machine that I'm starting to install:
Hydraulic cooler and filter kit ($375): After spending more time than I care to admit trying to come up with a suitable chain of parts, I decided to go ahead and buy this kit. I still believe it's possible to make this...
I went out this morning to check on a couple of things, and I noticed that the bracket of the house for mounting the boom is shaped like a bowl. Effective as one too; there's a half inch of water trapped in it. I suppose drilling a small hole is in order, so it can drain. Gotta give that one...
Here are links for the parts that I have purchased, though only the thumb has been delivered and installed at the time of this writing:
Hydraulic thumb - Many identical/similar units available from a variety of sellers, all likely produced at the same factory/factories. The cylinder looks...
I posted a picture of one of the tracks. I can't see the drive shafts directly, but perhaps the picture is enough to infer? Otherwise, I am sure to throw or replace a track eventually, and I'll take a better look when that time comes.
Your thread has grown to contain dozens of intertwined topics. While I have spent the last week working to read through it from beginning to end, I am still not done making my way through all of the posts there. There are so many people chiming in and posts almost constantly jump between topics...
As my last post indicated, the new hydraulic thumb arrived today, so I took some time to get that installed. It would have been a quick job, but there were no grease fittings in the cylinder rod eye and the thumb pivot points. Consequently, I spent a little time drilling and tapping ports for...
I managed to take a few photos of my machine today before/after installing its new hydraulic thumb. My Sany and Komatsu are in the background of the first. The last shows how I’m keeping it dry when not in use, until I can clear out some space in my garage (or I finish working on it and drive it...
Performance wise, the machine ran great with the throttle set at 50%. Of course, raking up needles with the cleanup bucket wasn't exactly pushing its hydraulics to their limits, but the lower throttle setting did make it easier to get smooth motion out of the controls. It's definitely more jerky...
For my mini’s first feat, I cleaned up the sequoia and cedar needles that fall between my house and adjacent cottage. You can see there isn’t much clearance, but I was able to get everything pushed into a pile. I did manually rake along the cottage, but that was nothing compared to the amount of...
I had a chance to get out on my machine today and get some work done. The pictures that I took (coming shortly) aren't the best to show it off, but they do show why I chose to buy a smaller machine. Plus, I will be out less than $6K for the machine and attachments, even after all of the upgrades...
I have a digital endoscopic camera that I will use to inspect the tank. These cameras are inexpensive on Aliexpress (~$5), so I have dedicated one for checking my machines. It's great for looking in tight spots, and that describes a large percentage of their innards.
As for grease, I have a...
This past weekend, I decided to buy a mini-excavator via our local heavy equipment auction house. I had been watching their site for several months and noticed that these were selling for a reasonable price. I wanted to share my journey here, because I could not find any recent threads anywhere...
It now has been almost three years since I bought my SY35U excavator. In that time, I have put nearly 300 hours on the machine here on my farm. While that's not much by most standards, it's enough for me to know the machine fairly well. I still do not have a lot of pictures, but I will share...
I have put around 20 hours on my new machine at this point: pushing over small trees and digging up stumps with the ripper tooth attachment, turning and loading compost, and few other odd jobs here and there on my farm. After reading the manual, I learned that a 100-hour break-in period is...
I had hoped to hear back from the dealer sometime on Saturday, but that didn't happen. So last night, I went ahead with my plan and wrote to the Sany America service address (and cc'd the dealer) to report my issues, along with a link to my post here. In a surprising turn of events, I received a...
Hi all,
My Bobcat 331 started overheating last Fall, so I started looking at rebuilding it. I signed up here and posted about its issues in another topic, so I won't rehash those details here. However, I knew a rebuild would be a stretch (both in terms of time and money), so I spent a lot of...
I am not sure the engine needs a "full" rebuild, but I decided that it needs more time and money than I want to put into it in one shot. I've put it up for sale on Craigslist, and I've had several people contact me about it. If it doesn't sell, I start looking into rebuilding it and revive this...
I have not dug into the machine to determine exactly what's going on, but bearings started squealing and the engine now overheats fairly quickly. It got warm enough to kill the fuel pump, which probably saved it from worse damage. Given the symptoms, I suppose that it could "just" be the water...
Thanks for this reference. I looked around the site and couldn’t find a v1902…. Is there a newer model that would drop into place?
I think the rest of my my excavator is in good shape, but it’s definitely a tough call to evaluate the trade offs here.
I am trying to decide whether it will be worth the effort required to rebuild the Kubota v1902 engine in my '95 Bobcat 331. This would be a much bigger undertaking than I have ever attempted on my own. Rebuild kits seem to be readily available, but that path assumes that you know what you are...