L35 - BT900 Separation and Derusting

[Nicksacco]

Hi All-

After almost 5 years of ownership and restoration, the time has come to separate my L35 from the BT900 backhoe.
I've restored nearly everything about the two units - except where they connect.
Hmmm, I needed inspiration.

The Mount Release levers were frozen to their pivots in a seemingly permanent bonding of rust.
Unable to move the levers, meant the BT900 was on there for good.

Then I managed to find 2 brand new wheels and tires for the rear and I was immediately inspired!
My original wheels were cracked and I repaired them years ago with welding. The tires, hung on by a thread.

So here's a few pictures of what I did to loosen the Mount Levers and remove the backhoe.
I'm in process of removing rust and prepping for paint at the moment. I'll add to the thread as I go along.


Here is a shot of one of the Levers.

I cut a slot in the pivot tube with a Dremel and 1.5" cutting disk.
That's so the metal would expand after heating and using penetrating oil.
I drilled out the roll pin so that I could move the lever back and forth after I got it to move.

Here's a shot of one side of the assembly that holds the backhoe onto the tractor.
When you move the Mount Levers back and forth, they move the pin with the square piece between the "grip Jaws" which locks the backhoe to the tractor.

Now I can finally clean and paint both backhoe and tractor where they join!

Here's one side of the tractor cleaned and ready for some Ospho and paint.
Hmmm, might have to do some welding repairs while I'm at it!
How do you like my redneck jackstands?

MORE to come.....

 

[L35]

When I bought mine 17 years ago mine were seized also. It was a fight but I won. When I reassembled I anti seized the parts so they wouldn’t give me any issue. Now it stays undercover 99% of the time so that helps as well.

 

[Nicksacco]

Awesome! Did you have to cut the pivots as I did or were you more patient and gentle?

 

[L35]

Heat, penetrating lube, lots of back and fourth. Broke the handle off one side when using a cheater bar on it. Welded back on.

 

[Nicksacco]

CONTINUATION OF THE L35's RUST WORK.

Since I posted last, it has been an interesting working through the last bits of rusting on the mo-chine!
But good news.
With most of the difficult parts of this process completed, I'm getting closer to painting.

This picture shows the left axle and Frame Support as I'm removing the old bolts and nuts.
As you can see in some pictures, there isn't much of a head on the cap screws left.

The assembly for the 4-16mm hold-down Cap Screws includes a "Spring Washer" on either end (think something like Belleville) and 2 nuts.
The assembly for the 3-14mm Flange Cap Screws on the side include a Split Washer and a nut.

There was no point trying to use an impact or any kind of wrench because everything was "welded" together with rust and there was no way I was salvaging anything.

So, out came the angle grinders and off came the heads. With some help from my sledge, and some PB Blaster, the Cap Screws were coaxed out.

One Cap Screw was more stubborn than the others.

And yes, I did add some metal to the frame tube after cutting out the old rusted metal.

Here I'm in the process of removing rust from the axle.

After removing the rust on one day, the next day I noticed "weeping" and of course, more rust forming.

I read about this phenomenon, and learned that after cleaning metal, the pores of the metal can weep - releasing trapped water - especially if two pieces of metal were clamped together.
In this case the 2 pieces are the Axle and the Frame Support.

Not to worry, I have to wash the whole thing down before I paint to remove any oily products and then I'll be coating with Ospho and Coroseal (based upon location) prior to painting.


I thought you might like to see some of the cap screws removed in comparison to the new ones.

CONTINUED BELOW

 

[Nicksacco]

I also found an excellent company in Florida called G&T Engine Parts

G&T ENGINE PARTS - Original diesel engine and spare parts made to fit aftermarket parts fits: CATERPILLAR, JOHN DEERE, CASE NEW HOLLAND, INTERNATIONAL TRUCK, KOMATSU, AGCO, INTERSTATE MCBEE, KUBOTA, BOBCAT, CUMMINS

The reliable supplier of diesel engines, heavy duty machine parts and diesel truck parts.

gtengineparts.com

The sales lady was Irene Breshnev and I had the parts in 3 days.

They had every part I needed for this project and at a very reasonable price.
AND the parts are all OEM Kubota.

Below are the parts ordered:

One more time:

The project continues...

 

[L35]

Outstanding work!

 

[Nicksacco]

Much appreciated!

 

[Runs With Scissors]

You're doing an outstanding job sir!

Being from the “Rust Belt”, I have a pretty decent understanding of how insidious rust is.

Keep up the good work, and nice job posting about it too!

 

[Nicksacco]

Thanks for your support!
More to come.

 

[PoTreeBoy]

Looks like it's my turn in the ring. I was showing an old pilot friend my shed and tractor. He asked if if always leaked. I thought he was referring to the occasional oil drop and said yeah, it's like an old radial engine it's supposed to leak. Then I looked again and there was a puddle of clean fluid under the backhoe boom pivot. I thought it was going to be the boom cylinder. But after he left I fired her up and when I swung the boom, there was a stream coming out of one swing cylinder. I know the swing trunnions, pins and bushings are worn, so this is time to see about getting that all fixed, so I need to remove the hoe. I doubt it has ever been off. Sure enough, the levers are frozen. I got the snap rings off and soaked it with PB Blaster. Tomorrow, if the PBB hasn't worked magic, I plan on removing the tire so I can get a torch and hammer to it. Wish me luck.

 

[Runs With Scissors]

Looks like it's my turn in the ring. I was showing an old pilot friend my shed and tractor. He asked if if always leaked. I thought he was referring to the occasional oil drop and said yeah, it's like an old radial engine it's supposed to leak. Then I looked again and there was a puddle of clean fluid under the backhoe boom pivot. I thought it was going to be the boom cylinder. But after he left I fired her up and when I swung the boom, there was a stream coming out of one swing cylinder. I know the swing trunnions, pins and bushings are worn, so this is time to see about getting that all fixed, so I need to remove the hoe. I doubt it has ever been off. Sure enough, the levers are frozen. I got the snap rings off and soaked it with PB Blaster. Tomorrow, if the PBB hasn't worked magic, I plan on removing the tire so I can get a torch and hammer to it. Wish me luck.

If possible, I might keep soaking it for a few days.

It’s hard to judge exactly how long is “good nuff”, but I have found that “longer is better”.

But, as I well know, there are always those cases where the “Flame wrench” is required.

Good luck.

 

[Nicksacco]

Goodluck @PoTreeBoy

It might help you to search threads on "BT900 Refurbishment and Fun".
You don't have to remove the backhoe from the L35 to access the swing cylinders.

However getting those Release Levers moving again is worth the time.

 

[PoTreeBoy]

Goodluck @PoTreeBoy

It might help you to search threads on "BT900 Refurbishment and Fun".
You don't have to remove the backhoe from the L35 to access the swing cylinders.

However getting those Release Levers moving again is worth the time.

I wasn't sure if they were removable like that or not. I've been putting off the refurb, but this leak may be the impetus to do it. I've been thinking about removing the backhoe just to get the experience, so this thread was timely.

I remember your refurb thread and I'll be referring to it I'm sure. My thought is to remove the swing frame and find a machine shop to do the work.

 

[PoTreeBoy]

Goodluck @PoTreeBoy

It might help you to search threads on "BT900 Refurbishment and Fun".
You don't have to remove the backhoe from the L35 to access the swing cylinders.

However getting those Release Levers moving again is worth the time.

I got a late start but, after removing the wheels for access and applying more PB Blaster and shop hammer, got the levers moving and the hoe sitting on the floor with the hoses still attached.

The removable procedure calls for setting the main frame on the floor, but that's going to make working on those cylinders pretty tough. I could prop it up on stands, it seems rock steady on the stabilizers. But the only thing that gains is having the tractor out of the way and I'm not sure that really gains anything. Hopefully tomorrow I can get the cylinders off, repacked and assess the trunnion condition.

At least I know now how to remove the backhoe, and that it's in condition to do so.

 

[Nicksacco]

Nice! Glad to hear you were able to separate tractor from backhoe!

Part of my problem was not only the horrific rust, but a prior abuser applied some kind of cheap paint everywhere. (never heard of masking things off)
That paint got sucked into cracks and crevices and only helped to seal in what was already rust damaged. A nightmare.

The BT900 removal procedure described in the OM was confusing to me but once I saw what actually was taking place - It made sense. A fabulous design.

 

[PoTreeBoy]

Another late start, Harbor Freight has a sale on (when don't they?) so I picked up a pair of jack stands and a 3T floor jack on sale. Also some 6pt impact sockets and adapters in case something is really tight.

The swing pins slid right out, I haven't measured them but they seem to show little wear. The bushings have noticeable wear front to back. The top support came off without too much trouble. I had to reconnect the tractor and raise one stabilizer to have clearance to slide it out. Good thing I had those new jack stands! First glance at those bushings doesn't show enough wear to cause the slop I've seen, so I'm afraid the cylinder trunnions are in bad shape. I did run into a guy in HF who gave me a hydraulic shop referral not too far away that should be able to repair them.

The first thing I noticed when pulling the tractor away, after removing the backhoe, was how much heavier the steering was! I'll definitely have to install the 3ph and put something back there if I use the tractor while the backhoe is off.

 

[Nicksacco]

Interesting @PoTreeBoy
I only turned mine around after removing the BH so I could put it in the barn.
This makes me think that liquid ballast (or similar) will be needed if operating w/o the BH.
Currently my old, beat up tires contain calcium chloride. I'll never use that.

 

[Nicksacco]

CONTINUING THE WORK.....

At present, I am taking a rest from the grinding, and swearing.
I've coated the L35 with Ospho, and giving it a couple of days to work its magic before painting.
Here's the story:

I researched the use of Ospho on the Internet and after several YouTube "experts" collided on their procedures, I decided to contact the Ospho company and speak to their expert. Thank goodness.

Much of the information I found on the Internet was completely incorrect. The instructions found on the Ospho site were usually completely ignored or "modified" which likely would reduce the effectiveness of the product.

Ospho is NOT a paint. It is not meant to be sprayed, nor is it meant to be sanded once dry. Epoxy primers are not recommended, and metals treated with Ospho are not recommended to remain unpainted long term.

Ospho is meant to be applied with a brush and only a very thin coat. The product acts like water when applied, meaning that it is very thin. The brush should not be dripping wet. More is not better.

Some key information given to me by the Ospho rep is as follows:
--Ensure the chunks of rust are removed
--Ensure that the surface is very clean
--Ensure that the metal is not oily - recommendation is washing with dish soap
--Curing is best if the metal is not subjected to high humidity while curing
--Cure for 24-48 hours
--Apply sparingly and avoid Ospho dripping and running everywhere
--Avoid contact with concrete
--Do not sand the finish after applying
--Use an oil-based primer on top of Ospho
--If after curing, there is a white powder (that means you used a bit too much), wipe off with a cloth having a tiny bit of mineral spirits on it

Something I noticed after brushing on Ospho, is that the magic begins fairly quickly and the coating gets thicker as it begins to cure. Thus don't keep going over it.

Ospho has a strong "vinegar-like" caustic smell and you definitely do not want this in your eyes or on your skin. It started burning my skin after contact but a rinse with soap and water was all that was required.
Some ventilation would be recommended during application.


So here's where I am in the process:

Cleaned and prepped for Ospho:

I put a small wedge under the axle to raise it slightly and used a hacksaw blade to get rid of rust

I used a homemade brush tool to clean out the frame tubes. The "Derusto 2000" is made from a chimney brush welded to a steel rod. Chucked in a drill it was fabulous.

A thick new tarp was placed under the machine

A foam cannon was loaded with Dawn soap and the unit was washed and scrubbed twice

After drying for a day, the Ospho was applied. The black parts show the rust being changed to Iron Phosphate

Another homemade tool - the "Sponge-O-Matic was used to apply Ospho inside the frame tubes

 

[Nicksacco]

Here are other things used in this project.

The most valuable tool is this Optrel PAPR system for grinding and blasting. It will save your lungs.
This can be found on Ebay for about $350

The brush used on the Derusto 2000.

The Soap Cannon