1987 LJ70 frame swap + mods build thread

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Winter is coming. Last year with just the gravel floor wasn't great. As snow and ice built up on the reast of the yard the tent became the lowest point and filled with water once it started melting. So, I put down some pallets as a floor. I will also make walls on all three sides instead of just one.
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I got a very worn tractor tyre from a friend that is pretty much the exact dimensions of a 33x10.5-16. Will be useful for designing bump stops and mud flaps, and in deciding between 33s and 35s. Why isn't 34x10.5-16 a common size?
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It will sit about 4cm higher than this, I couldn't jack it up any more as the roof rack hit the ceiling.
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I've also made some progress on the electrical wiring for the air suspension. Getting the valves to work has revealed a lot of leaks. Luckily they're in the treads and not the shark bite fittings, so it's just a matter of tightening or redoing with more teflon tape.
 
The tent now has walls on three sides. I haven't yet decided how to make the last wall if I even need one at all, as I have to be able to get the cruiser in and out.
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The winch PTO shaft is installed. I decided to weld a plate to the engine mount and bolt the original HJ60 carrier bearing bracket to the plate. I still have to make a reinforcement plate closer to the front bolts
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The shaft is originally off a HJ60 but has been lengthened to fit a HJ61 by a solid piece of steel that fit inside the tube. This made shortening it to fit the LJ70 pretty simple, just cut the extension, remove slightly less than needs to be removed from one side, insert the solid bar and weld.
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I went and bought a belt for the compressor yesterday, and today I threw together a tensioner. A timing belt tensioner wheel off a Citroen, half an adjustable wrench, and some cut off pieces of a shackle, door hinge and turnbuckle. With the belt in place I can see that the compressor needs to come forwards a little bit, but that should just be a matter of some washers and possibly some reinforcement of the rear mount.
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Over the last week I have welded up most of the exhaust. It will exit in front of the right rear wheel, and the plan is to mount it solidly to the frame by welding clamps to the front body mount and the exhaust hanger.
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I have also mocked up most of the OBA system. The design plan has changed a lot after I've learnt that a water separator only separates water, not moisture. Both 5.5l tanks will be mounted at the back, I won't use the 12l at all because it's in questionable condition, and I'll run a steel pipe under the cruiser as a sort of radiator.

I then got started on welding up the left side door. I want to put the front back together so I can get the wiring and plumbing sorted out, and the doors go on before the wings.
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Got the door mostly finished (forgot to tidy up the bottom edge and needs a bit of grinding) and mounted, though it might be easiest to remove it to finish the bottom edge and reinstall the seal.
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I also mounted the left wing to tidy up the wiring in preparation for a first start in the new frame. Hopefully everything is done enough that I don't need to remove it again.
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I've been hesitant to weld the inner fender, at a glance it seems like an impossible eternity project. Once I got started it wasn't that bad though.
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The rear edge will be a bit more interesting. I haven't really decided how I will fit it in with the rock slider and mud flap. Easiest might be to extend it a bit to get it flush with the bottom of the slider and weld a tab to bolt the mud flap to somewhere, maybe as a part of the slider mount.
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I also remade the engine mounted exhaust mount. I'm not really sure why it exists, but as I'm using a flexible tube instead of a pipe it helps a lot in getting the tube under control.
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If I use a temporary fuel tank I could start it tomorrow, as I just need to get the other wing mounted to tidy up that wiring. I might just wait until I have a radiator and fuel tank though, so I can let it get hot enough to run smoothly and see how it sounds with the exhaust and snorkel.
 


Got it started today. I decided to install the radiator, but making brackets and finding or buying hoses for a fuel tank seemed like too much work so I'm just using a plastic bottle in the engine bay. I have the filter connected though.

The left wing shouldn't have any reason to come off again, so I mounted some accessories. The bumper is a great footstep for working on the engine, but it might be a bit in the way for offroading with how low it is. I don't want a tubular or angular bumper though, so it'll stay like this for now.
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After a long christmas break thanks to sickness and extreme cold weather I'm back in the garage. I've been welding a bit of rust on the inner fender...
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...and got started on the rock sliders. 80x40x4 U-section welded in place of the rusted out rocker panels, which will get built out with 45x45x4 angle and 40x4 flat bar to reach it better with a hi lift. The original plan was 50x120x3 square tube, but one of those are over 100€ so I decided to use what I have laying around instead. Just had to buy the flat bar for 13€.
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Since it's scrap metal there wasn't any long enough pieces, so I have to weld two together per side. I also tacked on some of the angle iron to see if it sticks out far enough for the hi lift. It does, and quite perfectly at that.
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The left side slider except for reinforcements to the body is fully tacked and partly welded.
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Thanks to my low budget design there's an edge for the hi lift to grip.
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CAD model of the front reinforcement/mud guard. Will get welded to the slider and the body, and possibly bolted to the wing.
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All the welding on the left side should be finished, except for the underside of the slider but I don't really want to do that in a polyester jacket so it'll have to wait until I get a leather welding jacket. This means it's time to turn the cruiser around to do all the welding at the back and on the other rock slider.
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the pinch weld around the front half of the left rear fender had broken from rust and heavy forces.
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I also decided to make a waste oil burner that I might put in the tent if I can find an extension for the chimney.
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After more way too cold weather to work outside, except for one day when I turned the cruiser around, I continued work today. For once I decided to do the smart thing and finish the rear axle before I make a rear winch mount and put the floor back in place. First up: the panhard rod mount.
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Second up: left shock mount. Except I have to remake it. I cut off the rusted out original one a while ago and have since lost it. Without a template I had to measure and eyeball where it should go, and focused a lot on ground clearance and completely forgot that I have to fit a spring behind it. I have a plan how to extend it in a sane way without having to cut it off again though.
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Don't mind the bushings, I ran out of rubber ones and I didn't really feel like sanding down poly ones to fit. At some point I'll have to make custom bushings that actually fit well, either by machining the poly ones or 3d printing with TPU.
 
I removed the invasive shock mount, and made one spring mount today. Despite the coil spring it's an air spring mount.
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My plan for the fuel tank and backseat, optimised for offroading. I will put the rear winch, air tanks and batteries under the floor where the fuel tank used to be.
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After a few days of hard work I have oil in the axles and gearboxes, the rear suspension done enough and a fuel tank mount partially made and the fuel tank installed.
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With working fuel, suspension and transmission it was ready for a test drive. The suspension is absolutely fantastic off road. A bit stiff in the rear, but it's getting much heavier and might get air suspension.

The articulation was a bit disappointing at about 17cm per axle, or RTI a bit over 400. I'm expecting it to be better with better traction though, and the air suspension should help a fair bit.
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The rear bumper is getting re-engineered. I like how it looks, but not so much how it's made. Some 50x100x7 U-beam along the bottom should be enough reinforcement, and the side mounts have been moved up to get the bottom of the bumpers flush with the bottom of the frame.
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The footstep has also been upgraded from extruded aluminium to rebar and 8mm steel.
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To make room for the fairlead and a recovery point (not yet made), the right bumper has gotten a fancy cutout. The lower part is at approximately the same height as the stock bumper.
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I'm replacing the lights with smaller universal units, which means replacing the plastic surrounds with rebar to make it look better and a bit stronger.
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I also replaced the rusted out bottom corners with the same 40x80x4 U-section as the rockers, except upside down to make it look a bit better as I don't need the 45mm extensions here.
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Made two tow hitches from two tow hitches, one for off road use with my military trailer and one for on road use with standard trailers. ~65cm and ~40cm tall respectively. The lower one will get diagonal braces to the frame.
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A bit of rust welding while waiting on brake parts.
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The license plate light wasn't in the best condition. I haven't yet decided between fixing it or ditching it for universal units.
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I decided an air hose reel would be useful. Active and currently hooked up to my workshop compressor.
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33s looks good!
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