Raising the rear tub

[sickpup]

Morning all, hope you're good.

Finally getting around to doing my rear X member with a 1/4 chassis, yep its that bad.
I'll be making up some jigs that bolt to the shackle mounts so it can all be held accurately in place but it occurs to me that as the 1/4 chassis will go so far back over the original chassis I will have to raise the tub so the top of the chassis can be welded.

As I can't look at the moment, the back of mine is full of parts, how is the tub fixed to the chassis and seat box? I don't need complete removal, just enough movement to raise the tub a couple of inches to get a mig torch into place so a pivoting is fine.

I know I'll have to remove the hardtop roof and door as well, not a problem

[Opossum]

Hi there,
If you can, possibly remove the tub completely ?
It will give you total access from above and ease of work, plus, a way of being super accurate in placing the remplacement part.
I have to adress the exact same situation on my LWT, and this youtube video is inspiring I find, especially the setup he makes to ensure perfect setting of the rear quarter chassis...
He's not doing this on a LWT but the approach is the same :

https://youtu.be/Ulmhh4m5NNw?si=xTqJZZ9wNDHLrZCb

Hope this helps,
Cheers,
Walter

[sickpup]

I have a shortage of space and problems with vandalism so completely stripping isn't an option although taking the floor out could be one way of doing it. I'm happy to tack my jig to the chassis so that's not a problem either.
The rear Cross member has pretty much fallen off along with one of the chassis rails. The rear of the chassis is floating at the moment, its supported just behind the fuel tanks with a bar on oversized axle stands.
I can build a jig using the spring hangers and tacked to the chassis, then measure to make sure the new 1/4 chassis is in the correct position. The spring hangers position is relatively irrelevant as to the position of the cross member and the tub as the spring shackles are self adjusting within reason. Afterall, you never know how accurate the replacement chassis part is, you just hope its good.

[AR4412]

Obviously the bolts holding the tub to the rear cross member will be out of the equation, so if you remove the seatbelt stalks, lower seatbelt mounting bolts, and the two bolts each side holding the tub to the outriggers, it's only being held by the seat box bolts and the roof. You shouldn't need to remove the roof, just loosen/unbolt it from the forward body mounting bolts and the windscreen frame so you can lift it slightly to break the seal to the screen frame. (You might need to run a ruler/blade along depending how well it's stuck down.). With the doors open/removed you should then be able to jack the tub and roof up as one slightly to gain better access. If needed you could unclamp and lower the windscreen frame allowing more forward movement of the roof panel. If still more lift is required you would need to remove the gearbox tunnel, unbolt the sills from the footwells and remove the two bolts holding the front of the seat box to the chassis. A 'hobby' MIG is easier for this work as the tip is a lot smaller than a euro-torch industrial type of machine giving better movement in tight spaces.

I think that's about it, except for the wiring that needs to be removed so that you don't cut through it when removing the rot, or melt it when welding in fresh metal.

Regards,

[sickpup]

Thank you for the highly detailed answer.
I have both Hobby type and a full on Euro torch equipped so that's no problem. I also need to remove underseal beforehand so the extra space will be needed.

[brosce]

I’d definitely take the floor out if you can’t lift the tub much. Having that extra access will make welding the new quarter chassis a lot less awkward.Broken Screen

[AR4412]

Given all the nuts and bolts for the lashing points, rivets, and spot welds that need to be removed to get the floor out, it would be easier to remove the complete tub.

Regards,