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Rear cross member


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Hi,

Having tried jacking my 90 up on the back jack point and having the cross member bend and generally deposit large amount of rusted metal on the road in the process, and a large hole appearing by the side of the jack point, I figure I will have to replace the rear cross member just to get it through the next MOT.

I've had a look at some threads and some some people have said the cross members on Paddocks aren't bad but has anyone got any other suppliers that they would recommend or avoid?

Another question, and the main point of this thread, is if I get a new cross member with the extensions how do I cut out the old one in the right place and whats the best method to cut it?

Do the extensions just go over the top of the old chassis rails and are then welded in place?

Thanks for any tips and help anyone can provide.

Steve

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The new crossmember has quite large tabs on it that fit over the cut ends of the chassis. Because of the large size of the tabs there is quite a bit of adustment to get it all lined-up correctly. There are 5 small tabs right at the back of the new crossmember that are used to bolt the rear of the tub to it and you need to measure from the inside of one of them to a position within the ends that overlap the old chassis ends. This is the same mearurement you make on the old chassis and then cut it off. When you fit the new crossmember, it should overlap the old chassis by as much as possible with the 10 bolts at the rear holding it in place and keeping it in the correct position.

If you intent to use the new crossmember for towing/recovery work, then be careful of the quality of the one you buy. Paddocks in general have a good reputation, Bearmach ones are a bit variable :-

110 - perfect fit and good quality construction-

med_gallery_2_28_491.jpg

90 - good construction, but the tape measure they used was faulty!

med_gallery_2_315_179136.jpg

Series 3 - made out of baked bean tins (no crush tubes, poor welding, etc etc etc. :lol:

med_gallery_2_123_613354.jpg

Don't forget that the wiring loom runs inside the chassis rail on the drivers side, so either remove it entirely and fix it to the top of the rail, or cut and join it back together once the new crossmember is welded on.

Les.

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Many thanks Les,

I might have to do this quite soon.

Luckily my next door neighbour is a welder and a Landy fan so he's offered t do any welding for me.

So as long as I leave enough of the old chassis for the new bit to slot onto then I should be ok, as long as it's within the boundaries of the new large tabs?

Do you know what happened in the case of the faulty tape measure? I'd obviously be keen to avoid that happening to mine.

I'm also thinking of spraying the cut ends in waxoyl before putting the new bit on.

What would be the best way to cut the old chassis?

Steve

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I assume that it's going to MIG welded? If so then you can waxoyl to within a few inches of where the weld is going to be, but let the waxoyl set for a couple or so days before fitting it, or as Ivan says - it'll catch fire. Try to have as much overlap as possible. Some people also make a hole through the tabs and puddle weld the new to the old to add extra strength.

Les.

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Thanks Les,

Yes I would presume MIG welding as well, I just leave that up to him.

I'm still quite nervous about cutting at the right point.

If i measure from the small tab to the end of the extension and, for arguments sake, the large tabs are 6 inches long, I can cut the old chassis off at anywhere in that 6 inch tolerance, but making sure that the old chassis has enough left to slot in, so I would probably allow about 5 1/2 inches of the old chassis to overlap inside the large tabs?

Am I understanding this correctly?

Thanks again

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You're going to want as much overlap as possible because the corners of the large tabs should be welded together and to the original chassis inside. If your worried, why not cut off too little and then try fitting and removing a little more each time. I think that on good quality replacements the tabs are stepped out a little so that they fit nicely over the original chassis so ideally you will want to slide the original chassis ends right up to the step.

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Before you cut anything off ................. weld a piece of 50x50x6mm angle between the chassis rails just forward of the cutting point ;) .............. this helps to ensure alignment is perfect for the replacement, then cut out the angle when the job is complete ..................... without this bracing the rails can spring as you chop away the x member

:)

Ian

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Before you cut anything off ................. weld a piece of 50x50x6mm angle between the chassis rails just forward of the cutting point ;) .............. this helps to ensure alignment is perfect for the replacement, then cut out the angle when the job is complete ..................... without this bracing the rails can spring as you chop away the x member

:)

Ian

Good tip Bull bar, could you just brace it with a farm jack or something rather than welding in a new piece?

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If the new cross member is being waxolyed then would be a good idea to clean the chassis as far down as possible after cutting the rear cross member and getting some waxoyl in there prior to welding.

Keep a hose pipe and fire extinguisher handy (powder should be best) and disconnect the battery just in case you sever some wires?

Drill a hole after welding to get some waxoyl to the bits you missed, a compressor driven gun with multi-directional nozzle on the end of a flexible tube is best for waxoyl. Use the clear waxoyl it is thinner than black and gets inside all the nooks and crannies.

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