Looking For Used TL421 for my B21?

[100 td]

Re: Straightening bent TL421 Boom on my B21!

My 2 cents worth, this is what I'd do, but YMMV!
Whilst you are probably correct, and can see where previous repairs have been done, before you cut, what was the measurement each side, from top loader boom pin mount to rear frame corner? Also from top pin down to lower frame?
Before you do any measurements/corrections, the top loader pins must be in the exactly same position in relation to the tractor frame. Until they are within a mm or 2, no point AFAIC as a small difference here will make a big difference out front. EVERYTHING is related to the boom top pin mount.
Whilst it's not an easy job to set up again, it's worth spinning your tractor 90 degrees in the shed, set it up again and redo all measurements and see what you come up with.
Why, 95% of concrete is of very poor level, and don't forget to check your jack stands next to each other as well. From factory manufacture jackstands set at the same height can be out 3/8"! If one jack stand is 1/4" lower at the front, the resultant difference at the front frame may be more than 1/2". So if the floor is 1/4" unlevel, or if the stands are out, it multiplies the error the farther you measure away from that point.
After ensuring the top pins are in exactly the same place, and you are on flat concrete, measure from rear frame corner to front bucket pivot pin on boom both sides.
If you cant get to the corner to measure, take your rear tires off and measure to the axle. Depending on your rear axle placement, it needs to be measured to the front corners of your frame first to ensure it's correct. Also check axle distance to frame each side. Once you are sure axle stick out each side is the same, and you have the same length to the front frame, you can use that as a measure to the front of the boom frame.
Lots of work here I know, and yes you could say I'm going overboard, but I don't believe I am, measure thrice, cut once!
Another way to work is to remove the boom, flip it upside down, measure and draw out the frame on some concrete with extended lines in all directions, place frame, using a large 3 foot square and straight edge, measure everything and project everything to the ground to see what needs fixing.
Have fun!
I'd give you a hand, but you're a bit far away!
On another note, a friend down the road has a problem with his loader, when the boom goes up and goes to full lift it cocks sideways at full stroke of one ram, I said, you never know , we'll have to measure if it's a Chinese different length ram, or something else not set up right. We have a lot of measuring to do!

 

[RobbieBones]

Hmmm. After thinking about this for days I thought I thought about everything. I built my home and when doing so I pitched my garage floor so everything drains out. So the floor pitches pretty good in one direction. Left to right it’s near level maybe off an 1/8 in 6 ft. At least where the tractor seats. Anyway I leveled the frame with hydraulic jacks then shimed the stands to meet the frame. I did this front and back. So I’m ok with the frame being level and think turning the tractor will not really help much.

However did not think on removing the rear tires and measuring back to axle so that the top of rear boom supports are square to at least the axles. And again from rear of frame to front of boom etc. Will do that tomorrow.

I did use a level on the underside of the main frame to help level the frame with the jacks. The photo with the level across the rear boom shows that there level. I actually checked to see if they were plum and they were. So if I can confirm them to rear of main frame or axles I’ll feel real good. When the FEL was off the tractor the bottom of the rear supports obviously moved in and out with the boom piston so instead of making a bracket to hold them square I put the loader back on the tractor after leveling it.

I’m a believer in measuring twice cutting once.

Even how lopsided the loader looks and with the old repair the actual length measurements aren稚 off very much 1/4 to less. It really is that the left forward end of the boom is pushed down and the left arm of the boom is pushed outward at the top of the curl piston. That outward bend is resulting it not equal cross measurements.

The old repair is welded wrong. The lower arm must have cracked and was welded butt to butt welded at the seam. I probably will correct it. I’m amazed I never broke it since all I have is rock on my property and abused the loader a lot. The bend was there when I bought it and I made it a little worse. Really surprised I never cracked that weld.

I also have an issue with the right inside comp link. It appears the old owner manufactured one and its off 3/8 causing the top pin and piston to tilt in and backwards. Ill post I picture tomorrow.

Thanks for your insight keeps me thinking.:thumbsup:

 

[100 td]

However did not think on removing the rear tires and measuring back to axle so that the top of rear boom supports are square to at least the axles. And again from rear of frame to front of boom etc. Will do that tomorrow.

I thought I mentioned that in a PM, maybe I didn't, but to me, it's critical.

What's the measurement in length of each side from bottom pivot pin on front of boom up to the round crossmember? If it's the same, meaning the welded repair is at least the correct length, I would flip the boom onto the floor and work at it that way. If it has a twist in the whole boom, have a look at that before correcting a slightly out of align "finger" on the end. YMMV
EDIT: Just re-read your post.
So after rechecking after establishing the top pin mounts are exact, look at the measurements again and see how they play out.
If I'm reading correctly, the finger length may be correct?

If so, I'd definitely flip and measure and then work out exactly how/where is the best/or easiest place to correct the main boom, either by partial cut and close or cut and fill. Correcting buy hydraulic force alone is very difficult, requiring a massive amount of stretch past the point where you want to end up. Depending on frame twist you may require the main crossmember to be cut (part or full) to realign the frame, and it "could" have a slight twist in it you may not see.

 

[100 td]

I also have an issue with the right inside comp link. It appears the old owner manufactured one and its off 3/8 causing the top pin and piston to tilt in and backwards.

It appears Link 2 may have been modified, hard to tell? Get some paint stripper and strip the entire end of boom, and all the links so you can really see what has been done, insert pins in boom and check for square, there may be more damage behind those links and the holes may not be square or in the correct place.

 

[RobbieBones]

Well after leveling the frame. I then used a 6ft straight edge across rear of frame to use as a point to measure forward to boom supports and then to boom cross member. I知 off 1/2 inch low side of boom to rear of tractor. Measurements to supports are good.

All the comp links are good except one. It appears that it was bent or remanufactured. And throws the radius off 1/4 of an inch. The arc on the remaining 3 links is 3/4 bent one is 1-1/2? See photos.

Lower boom bushings are slightly out of spec. Plan on changing them at later date. Pins are slightly out of alignment.

I知 planning on cutting the cross memeber and bending left side of boom up and in to make it square. Then align the pins.

The two lower attachment points on bucket need to be repaired and aligned. One collar or cleaves on low side of buck snapped off. I believe the misaligned comp link and pin on the upper opposite side put pressure on the opposite lower side causing the breakage.

 

[100 td]

Sound good, a bit of work but getting there, cutting the crossmember will make for easy rotation/correction of boom. Did you paint strip or wire buff the old repair for a look?

 

[RobbieBones]

Is there anyway I can go back to thread 10 and start a new post? Can an administrator do that for me?

 

[100 td]

There's only my posts since thread 10(and yours), if you don't like them let me know and I'll delete the lot, then you can go back to 10. EASY, just let me know.

 

[TomSeller]

Sound good, a bit of work but getting there, cutting the crossmember will make for easy rotation/correction of boom. Did you paint strip or wire buff the old repair for a look?

Good luck, you can do it!

 

[100 td]

What was the outcome, get it all straightened?