new to me cat 426 questions

[gusbratz]

Hello everyone, this is a great forum and I was hoping you guys could help me out with few questions. I just bough a 1989 cat 426 backhoe, this is my first newer piece of equipment. All my other stuff is 1960’s vintage and it is all very simple in comparison. I am not a professional I just do handyman stuff around the house. The cat is sort of a handyman’s special. The bucket and stick cyl’s are trash. The inside is all galled and scored up. The bits of metal got into the valve and made is mess up and the PO took off the cyls and blanked the lines and cleaned put the valve. He owned it for 12 years and looks like he did a lot of work to it in that time. Surprising because it only has 2200 hours on it.
1.) So I am wondering what would cause that to happen. He says the wear strips on the stick are worn and that caused the cyl to rub the inside of the boom. Not sure about that. But I need to find some cyl’s and change the fluid. I use DTE24 in my TD6 dozer and 530 case backhoe. Will that be ok? Manual calls for hydo. I am sort of scared of messing up the variable axial pump since it is new to me and seems high tech.
2.) He says he changed the transmission fluid and used rotella T 15-40. That doesn’t sound right to me. Im my case 530 case o matic I use tractor supply universal tractor transmission fluid. Would that work in the 426 Trans or should I drive 2 hours to the cat dealer and my some expensive cat stuff? I drove the cat 20 miles to get it home and it seems to go fine.

Thanks for any help.

 

[Chisumtrail]

Probably not same problem, we had 1 in the shop a few years ago. The end of the rod broke off, they weld it on machine with ground on the stick instead of the rod. It did the same thing had to change valve section and cylinder.

 

[gusbratz]

i don't think so, the seller was sort of vauge on what happened but don't think it involved welding. he said the valve got stuck then he found metal in it witch made him pull the cyl's. i am worried that the fluid is contaminated and i am going to have scored ruined cyls all over the machine. the loader stays up overnight so i guess it must be good. the packing is leaking on both hoe cyls and swing cyls though. first order of busness is fluid change all around once i figure out what is affordable.

 

[Nige]

I think your idea of a fluid change (I'd change the filter too although you don't mention that) is a good one. To get an idea of what might be in the system, try this - cut open the filter and then cut out a section of the filter media a couple of inches long and about 90-degrees around the circumference from about half-way along the filter length. Squeeze this in a vice to get all the oil out of it, then pull it open again and take a good look for brass or metal particles in the base of the "V" of the pleats.

 

[gusbratz]

heres a pic of the machine from the c.l ad,I picked it up for a scary low price. hopefully it works out. i have a lot of stumps to dig.

 

[gusbratz]

Drained the hyd system today and pulled the filter. I didn’t need to cut it open it has about a tablespoon of metal shavings in it. I am thinking that the ext stick cyl went bad and contaminated the other hoe cyl’s. The fluid looked like an ugly color of green. I am going to pull and hone and repack all the backhoe cyl’s at this point to make sure they are done right. I called cat to get a price for a bucket cyl. She says it is discontinued due to it being such an old machine. Its only 25 years old, if I was buying a new 40,000$ backhoe today I would expect it to be working in 25 years. But she said even if the cyl was available it would be 3500$. That is like monopoly money prices. Maybe if this backhoe was owned by a public utility they would buy one but not me. I can buy a 3.5” bore 30” stroke cyl from surplus center for 330$ and fab up some ends to make it fit my dipper. Why wouldn’t that work? On the cheap….. I have some quotes out for used cyl’s but I am thinking my idea is best. My other idea is buying dimensional honed tubing and taking it to the local machine shop and having them cut threads and a recess in the end and basically making my own replacement barrel for my cyl. Then reusing my rod and packing gland. Be just like a cat cyl but home made.

 

[mitch504]

Things to consider about the surplus center cylinder:

What is the relief valve set at for this function? If you use a cylinder w/ a design pressure too low, it won't last.

The rod size is critical for this application. If the rod is just a 1/4" larger, you will have a weak extendahoe, and will be sorry every time you spin the seat around backwards.


I would probably lean hard toward a new barrel for your CAT cylinder. You might want to check w/ a good hydraulics shop and see what they would charge to make it for you. Sometimes they are cheaper since they do it all the time, and they might have a piece of tubing, and you might only have to pay for 30", not 120".

On your transmission oil question, I have spent very little time w/ Cat TLBs, but if they are like their dozers and loaders and etc., it probably calls for something like a 40w TO4 spec oil. It is much more like a motor oil than a universal tractor fluid. I am not sure but Rotella T may actually meet that spec. I'll try to remember to look on the bottle tomorrow.

Good Luck,
Mitch

 

[mitch504]

Oops! Now I know how people end up with duplicate posts. I always wondered about that.:beatsme

 

[mitch504]

Here is Shell's list of compatible oils for your machine:

http://lubematch.shell.com/recommen...3477&site=58&region=371&language=18&brand=108


Here is the oil for your transmission:

http://www-static.shell.com/static/usa/downloads/lubricants/cs5861_43_sh_spirax_s4_cx_flyr.pdf

 

[gusbratz]

thanks! thats just the confirmation i was looking for. i emailed mobile about useing DTE 24 and they said:

"Caterpillar likes to use their HYDO product because if has a high level of
antiwear additives. Cat likes to see 900 ppm zinc in the hydraulic oil to
protect the pumps. The HYDO product has 900 ppm zinc per a publication
that Cat has. Mobil DTE 24 does not have quite this much zinc, but it is
a good oil to use with axial piston pumps. Mobil Hydraulic 10W does have
a similar additive package to the Cat Hydo oil if you had that oil
available."

warren lubricants has an anti wear hyd oil in iso32 grade and they boast:

"Coastal Premium AW Hydraulic Oils are superior anti-wear hydraulic oils formulated with high quality paraffinic base oils and an additive package that provides excellent protection against rust and oxidation. They also contain very effective zinc-type anti-wear agents that minimize wear in high-speed, high-pressure vane and gear pumps while meeting the lubrication requirements of axial piston pumps having bronze-on-steel metallurgy."

so i called waren lubricants and asked the zinc content and they said 400ppm.

I know rotella has like 1200ppm zinc and was wondering if i could use it in my hydraulic system. the viscosity meets the book specs and it may be nice to have a multi weight. i may go to the cat dealer and buy the TO4 for the transmission......

 

[Dickjr.]

I know in my manuel for a 416C you may use 15 40 rotella or dello. I use Chevron 10w motor oil ursla. I will check my manual for the trans.